Clutch fan conversion on a 55

[NTX5467]

The issue of pulley sizes and DRIVE RATIOS is one area that can be explored, but which also possibly has little knowledge base, generally.

 

In the world of Chrysler Direct Connection/Mopar Performance, the recommendation has always been to (at least on the B/RB 361-440cid) to use the "a/c water pump" with six impellers . . . rather than the non-a/c pump with 8 impellers . . . for decreased power consumption.  BUT as was later pointed out, the pulley ratio changes with a/c so it runs the 6-impeller pump faster so the ultimate water flow rates are not really affected. BUT as the water pump pulley drive ratio is altered for "more revolutions" per crank revolution, that also means the fan can spin faster, quicker, at the same time.  This might also play into the fan speed "effectiveness" percentage, also?

 

End result is that there can be several "incognito" (to the uninformed "naked eye") changes/upgrades which can make a synergistic difference for better performance.

 

Y'all please keep us posted on your progress!

 

NTX5467

[EmTee]

Has anyone tried Evans waterless coolant?  I'd be interested in hearing form anyone who has...

http://www.evanscoolant.com/

 

[JamesBulldogMiller55Buick]

1 hour ago, EmTee said:

Has anyone tried Evans waterless coolant?  I'd be interested in hearing form anyone who has...

http://www.evanscoolant.com/

 

most interesting !!

[Beemon]

I don't know if any of you watch Jay Leno's Garage, but they did a segment on this stuff and apparently it's boiling point is 310, so you don't need to use anything more than a 3lb cap to get the boiling point well above 210.

 

I've been trying to piece this stuff together with the part numbers in this thread, but I can't seem to find the fan blades over the counter. Did anyone have a part number for the actual fan or is that up to the aftermarket world?

[EmTee]

I've been thinking about trying Evans more for the anti-corrosion qualities given that my vintage cars spend most of their time parked.  The higher cooling efficiency is a bonus and I'm thinking that it may be just what KAD36 needs to gain the margin he's looking for with the addition of A/C to his car.

[KAD36]

NTX - will try the 18 inch fan first then find a steeper pitch 19 inch fan or a 7 blade in a yard and try that also - isteeper pitch may help air  pass through when freewheeling and provide more drag to ensure the HD clutch releases at right temp.  This may be trial and error but can't be too tough to get working right ( famous last words).  Heck these things cool 455s with AC.

 

Without knowing the actual flow rates or other specs it will be trial and error for knowing if moving coolant faster through the block with the high flow stat and verbally "improved" water pump is better or worse for heat transfer.  This is a motorad brand thermostat I got at rock auto.  Certainly at 500 rpm derated by 30% that 6 blade Hayden fan is not moving a lot of air for cooling, so we"ll see how some extra rpms and blades help - or hurt.  Maybe better start recording numbers for fair comparison.  If there are enough 90+ days left the time to cool down from 220 can be measured and will see which configuration works.  When I found the standard duty clutch I went to the 4 seasons web site and used a 65 Chevy Biscayne with a 327 as my sim-to and checked the measurements.  With a coupon at advance auto this experiment has run about 40 bucks for fan and clutch.  I'll post part numbers when I get to a real computer.

 

It's hard to understand how a free wheeling fan clutch with 2-3 inches of gap between it and the backside of the radiator can prevent effective airflow through the radiator at highway speeds.  A fixed fan may have a debit of costing engine power spinning at highway speeds but is also advantageously creating a low pressure area allowing more of the air blast to be sucked in at highway speed and go through the radiator - seems that way.  Maybe that's why in willies experiment the car successfully runs consistently cooler with the fixed fan.  The standard clutch definitely cycles on/off at about 200 deg on the gauge and Iit keeps my cars temp under 200 provided its left Idling in Neutral (650 rpm). In drive at idle (500 rpm) when it's 95+ out the car will get to 230 sitting in the driveway after about 20 - 25 min.  Rev it up in N, the clutch is full on (60-70% shaft speed) and it slowly maybe about 5-7 min comes down to 200-205 then the clutch goes off and will cycle on and off.  Clutch won't let it get down under 200 unless it's on the road moving, which is ok by me. Since the rebuild the car is running about 5-10 deg hotter on the highway 180-190 even with a 160 thermostat swapped back in, no difference between 4 blade and clutch fan in that scenario on a 90 deg day.  I'd be comfortable running this across country without AC.  It will not overheat, you have to accept however that disengaged at 200 deg the de-clutch fan appears to move less air than the 4 blade stock fan .  Engaged it will pull the temp down which the 4 blade did not do once the temp crested 215-220 in my application - it was almost like a thermal runaway that the 4 blade could not overcome.  Btw, the radiator was recorded 3 row a few years ago, not stock but supposedly similar to stock measurement wise and all these measurements were when temps outside were 95+  We all probably have subtle differences in our driven cars given parts replacement over the years so results will vary.

 

The water pump pulley speed is a whole different issue to move coolant through the block for optimum heat transfer. The rareness and price of an authentic 3 groove 322 water pump pulley or price of a new billet water pump/crank pulley is ill received so trying other approach out to see what an be made to work in the event that 2 AC compressor belts are to be used. Not there yet on the pulley design -  still staring at it. That's another thread 

 

Am going to try a few more things and report back although running out of hot days here to do the work.  Will look at the Evans literature - thanks Tim. My preference is to have a quiet engine driven fan that minimizes horsepower loss at speed, get aftermarket under dash AC to work well and keep the car as reasonably below 215 in a stuck in traffic hot idle situation as possible with a factory look.  Piece of cake (yeah right). 

 

 

 

[old-tank]

Even if you could live with a less efficient fan for the cooling system, the a/c will be less efficient and there will be more stress on that system too.

[NTX5467]

Quote

"Less stress  . . ."

 

At work, we had a 15 passenger BlueBird body bus to shuttle employees from the dealership to a remote employee parking area.  The a/c system used the factory compressor and added an aux condenser and fan under left floor area of the body for the rear a/c unit.  When the electric fan for that condenser would fail, it put all of the "heat" into the factory condenser.  A/C performance went down and the engine them would tend to run hotter, clatter more (even with the electronics to control such), and really run ssslllooooooooowwwer than it normally did (6.0L V-8).  Getting that additional condenser capacity use restored made a much greater difference than I would have suspected

 

In the summer, we used to get complaints from customers with 454 pickups who pulled trailers.  The complaint was "engine seems to downshift at highway speeds".  No transmission downshift, just the fan clutch cycling.  They heard the increased fan noise and suspected the engine rpm was changing, with a steady throttle.  Once advised of what was happening, all was well.

 

In almost all engines, there are a few flow controllers for the coolant flow.  In some, it was the metal "water manifolds" inside of the block, but almost ALL have the flow restrictions in the inserts in the cylinder head gasket(s).  Plus possibly some additional contours around the cylinder bore castings in the block.  Sometimes, little things make a larger difference.  I have an old Chevrolet book (done by Petersen Publications) which has many details of the engine designs of the small block V-8 and possibly the W-motor 348/409 engines.  In one section, it has a graphic of the coolant flow around the cylinder bore castings and spot temps at certain reference points.  Before and after some modifications to the coolant flow areas were made.  The temps were ultimately decreased about 20+ degrees with those small changes, plus some calibrated turbulence areas in the coolant flow.

 

I'm not sure which type of "impeller" the Buick water pump uses, but I'd think that an "impeller" would work better than something of a different configuration.  That's just me.

 

Thermostat rated temperature is when the thermostat starts to open, not the "full-open" temperature.  Many dirt track racers (and probably some others) don't use a thermostat as such, but washers with a particular size hole in the middle for a "calibrated restriction" for optimal coolant flow velocity through the motor under race conditions.

 

One time I needed a new water pump for my '77 Camaro.  It was after work so I went to an auto supply chain store I had bought things from previously.  I'd seen many of the "Saturday morning shows" which talked about water pumps with increased coolant flow characteristics being better, which seems plausible, so I got an aftermarket pump with visibly "nicer" casting areas inside of the pump housing . . . which should equate to better and more homogenous coolant flow.  One immediate issue was that the larger casting areas meant that I could only use an open end wrench on one of the bolts, rather than a socket and ratchet.  Took a little longer, but it was supposed to be better.

 

When I got things back together and full of coolant, I drove it home.  I noticed that the temperature came up as normal, BUT the running temperature was about 1 needle-width higher than it had been with the factory pump.  I watched it and it was consistent.  Better flow and higher temperature???  Not "as advertised"!!  It did work well, other than that, BUT when the shaft seal began to seep a good while later, I went back with an aftermarket "lifetime warranty" (the auto supply liquidated several years later) GM-casting water pump (pulled it out of the box to check before I got it, which the sales person helped me do).  With that factory casting pump on the engine, I again had clearance to use sockets on the bolts AND the temp went back down to prior levels.  As minor as that might have been, it just looked right as that was where it was wit the factory stuff on it.

 

The head gasket flow restrictions are not supposed to, but can increase in size with use and time.  This can allow the coolant to move too fast, possibly increasing turbulence inside of the cylinder head.  Results of that could be decreased spark plug cooling, higher cylinder temperatures with increased propensity of "clatter" (at stock ignition timing settings), and possibly a few other things.  Just one part of the total coolant modulation scheme of things.

 

There's a series of articles on cooling at www.allpar.com, by Daniel Stern.  Seems like he mentions the Evans product in those articles?

 

Some of these things can take a while to fully diagnose and then to formulate a set of activities to address the situation successfully.

 

NTX5467 

[KAD36]

 

7 hours ago, old-tank said:

Even if you could live with a less efficient fan for the cooling system, the a/c will be less efficient and there will be more stress on that system too.

 

So would it make sense a proper sized condenser with a clutch setup that could pull equivalent air across the condenser as a fixed six blade should be equivalent stress on the system - it would seem 200-210 wouldn't decrease reliability vs 180.

 

After thinking about this a little more, after 30 years on the road I haven't driven my car on long highway and stop/go trips in the 100+ heat of summer.  Going back and forth to Potsdam in spring and summer in college it was always in the 70s.  In the summer, it was a 15 minute drive to work on a back country road to the garage. Around town here, it was to local shows as the car over the past 20 years wasn't up to snuff for a long trip.  I'm not sure I have ever seen how the car did "baseline" in severe heat. 

 

It seems the first step would be to solve the running at 190deg even with a 160 thermostat in it at highway speeds.  That says that at 65 mph air blast through the 3 row radiator on a 95+ day with no fan assist there isn't enough cooling through the radiator to overcome the heat generated, and the system equalizes at 180.  Seems like that needs to get fixed first so that the fan only helps control the temp at low speeds and doesn't drag on the engine at high speeds.

 

think think think think......

 

PS - if going through a junkyard 30 min before they close and you see a good 7 blade 18 inch fan with a non leaking severe duty clutch for 10 bucks that fits your offset and bolt pattern make sure it is for the correct rotation before you pull off the shroud and take the fan off the vehicle..... grrrrrr.

 

 

Edited September 10, 2016 by KAD36 (see edit history)

[old-tank]

6 minutes ago, KAD36 said:

that at 65 mph air blast through the 3 row radiator on a 95+ day with no fan assist there isn't enough cooling through the radiator to overcome the heat generated, and the system equalizes at 180.  Seems like that needs to get fixed

That is perfectly normal on a 55.  Without extreme mods you will never get it to perform like a modern car where the temperature gauge never moves after warmed up.

[KAD36]

So based what you experienced on your car do you think it would have to go to a 4 row to have air at highway speeds bring the temp down or a radiator with even more capacity?  Anyone with a 4 row on their 55?

 

 

Edited September 10, 2016 by KAD36 (see edit history)

[Ben Bruce aka First Born]

I have always been told an engine runs more efficiently at 195/200 than at cooler temps. The 180 is the MIN temp the engineers want.  Thus the thermostat that controls the MINIMUM temp, having little if anything to do with the MAXIMUM temp.

 

  Ben

[avgwarhawk]

10 minutes ago, First Born said:

I have always been told an engine runs more efficiently at 195/200 than at cooler temps. The 180 is the MIN temp the engineers want.  Thus the thermostat that controls the MINIMUM temp, having little if anything to do with the MAXIMUM temp.

 

  Ben

The hotter they run the more efficient. Its carefully controlled now. Radiator fans that have several speeds. Multiple fan set up.

[Beemon]

Excuse my crude computer art, but I took the dimensions off the car and applied them to a 3D program to illustrate the inefficiency of the front grill (for 56, but 54-55 should be similar).

 

 

The first image is the radiator in relationship to the front grill. On the 56, the radiator was square 22"x22". It is placed 16" from the front grill and sits above the grill by 10". The perforated part of the grill itself is 10.5" tall and 56" at its widest, with a deflection of about 6" from the center. The second image is transparent with the fan shroud visible, an 18" diameter fan and a 6" clutch. The center of the clutch is about 1" from the top of the grill, where the thermostat would be. Aside from this, behind the grill is completely open with no deflection towards the radiator other than the splash guard, hood and inner fenders - all of which do not direct air. The last two images is a proposed shroud behind the grill and in front of the radiator, which only guides air into the radiator.

 

Because the thermostat is 1" from the top of the grill, all the air flow is mostly directed through the bottom half of the grill, and can conclude that not enough air flow is reaching the thermostat. Everything else behind the grill would create a flow dead zone, especially in front of the inner fenders.

 

Just wanted to apply a visual to the discussion. Other models may vary and this was mostly eye balled with rounded numbers.

[NTX5467]

1 hour ago, First Born said:

I have always been told an engine runs more efficiently at 195/200 than at cooler temps. The 180 is the MIN temp the engineers want.  Thus the thermostat that controls the MINIMUM temp, having little if anything to do with the MAXIMUM temp.

 

  Ben

 

About the engine temp and thermostat temp, in the middle 1970s, a friend was pondering the engine temp issue and ended up sending an inquiry to Edelbrock.  He got back a form with handwritten notes from Vic Edelbrock.  On the issue of engine temp, engine wear is greater at 160 degrees than at 180 degrees, Vic noted.  The 195 degree figures came about in the emissions era beginning in the later 1960s.  180 is supposed to be where optimum power happens, vs a cooler engine.  195 helps keep things warmer so that the engine temp assists in emissions control activities.  IF the system is designed to work at the higher temps (195-210 degrees), reliably, with a properly pressurized cooling system, no issues rather than the higher operating temperatures.  One reason why some engineers don't like numbers on temp gauges, I suspect!

 

I believe that by the middle 1960s, many larger cars had lowered the level of the radiator mounting so that the fan clutch was near the horizontal center of the grille.  As the 1950s cars had the radiator mounts on the same level as the front bumper "frame horns"?

 

Rather than roofing material, there is a thin rubber sheeting that has been used as water shields around the upper control arms.  It should be "somewhere" in "sheet" form.  Light weight and easy to work with.  Just need some plastic push-in "tree" retainers.

 

Another throught . . . Who's gong to be the first with a customized hood and "grille" in that hood nose section . . . for better air flow to the radiator??  LOL

 

Thanks for that great, graphic explanation, Beemon!

 

NTX5467

[EmTee]

4 hours ago, KAD36 said:

...That says that at 65 mph air blast through the 3 row radiator on a 95+ day with no fan assist there isn't enough cooling through the radiator to overcome the heat generated, and the system equalizes at 180.  Seems like that needs to get fixed first so that the fan only helps control the temp at low speeds and doesn't drag on the engine at high speeds...

 

Exactly -- that's the same conclusion I came to from Willie's experiment.  For the clutch fan to make sense, there needs to be a situation/scenario where air pushed through the radiator by the forward motion of the car alone provides sufficient flow through the radiator without fan assist. Another thing to consider is that the restriction may be that there isn't sufficient 'exhaust' opportunity for air entering through the grille to exit the engine compartment.  An example is an episode of Fast N' Loud where Aaron Kaufman built a Pike's Peak racer (Ford Falcon) which was overheating on runs up the mountain, despite new high capacity radiator, electric fans/shroud, etc.  Ultimately (as a last resort?) he cut a pair of vents in the hood to relieve the under hood pressure and no more overheating!

[avgwarhawk]

1 hour ago, Beemon said:

Excuse my crude computer art, but I took the dimensions off the car and applied them to a 3D program to illustrate the inefficiency of the front grill (for 56, but 54-55 should be similar).

 

 

The first image is the radiator in relationship to the front grill. On the 56, the radiator was square 22"x22". It is placed 16" from the front grill and sits above the grill by 10". The perforated part of the grill itself is 10.5" tall and 56" at its widest, with a deflection of about 6" from the center. The second image is transparent with the fan shroud visible, an 18" diameter fan and a 6" clutch. The center of the clutch is about 1" from the top of the grill, where the thermostat would be. Aside from this, behind the grill is completely open with no deflection towards the radiator other than the splash guard, hood and inner fenders - all of which do not direct air. The last two images is a proposed shroud behind the grill and in front of the radiator, which only guides air into the radiator.

 

Because the thermostat is 1" from the top of the grill, all the air flow is mostly directed through the bottom half of the grill, and can conclude that not enough air flow is reaching the thermostat. Everything else behind the grill would create a flow dead zone, especially in front of the inner fenders.

 

Just wanted to apply a visual to the discussion. Other models may vary and this was mostly eye balled with rounded numbers.

 

The fan clutch engages per Willies trials. However the temp is about 10 degrees hotter. It has been said several times the standard clutch spins about 50% of the shaft speed. Logically, cooling with the clutch is half of the standard fan. Installing the heavy duty at 90% shaft speed should cool like the standard fan if the fan pitch is 2 1/2 pitch. The reason Willie is attempting the clutch is to reduce fan noise. Mimicking the standard fan using a heavy duty clutch may not work in reducing noise. However, I believe it will as it did for the ever overheating 455 in my Estate Wagon.

Edited September 11, 2016 by avgwarhawk (see edit history)

[avgwarhawk]

Engineers don't care about numbers on gauges. The repair shops do. The average driver noticed their engine running at X degrees with some consistency. One very hot day the gauge is reading Y degrees. Oh my...my car is overheating! Its was 180 degrees yesterday. Today its 183!!! Lets head to the shop! Switching to a gauge with NORMAL in the area for the gauge arm to sweep solved many unwarranted stops at the garage. For many drivers, if the gauge needle is in the normal section of the gauge then all is normal. Its was a remedy for a problem that only existed in the drivers minds.

Edited September 11, 2016 by avgwarhawk
cause (see edit history)

[avgwarhawk]

17 minutes ago, EmTee said:

 

Exactly -- that's the same conclusion I came to from Willie's experiment.  For the clutch fan to make sense, there needs to be a situation/scenario where air pushed through the radiator by the forward motion of the car alone provides sufficient flow through the radiator without fan assist. Another thing to consider is that the restriction may be that there isn't sufficient 'exhaust' opportunity for air entering through the grille to exit the engine compartment.  An example is an episode of Fast N' Loud where Aaron Kaufman built a Pike's Peak racer (Ford Falcon) which was overheating on runs up the mountain, despite new high capacity radiator, electric fans/shroud, etc.  Ultimately (as a last resort?) he cut a pair of vents in the hood to relieve the under hood pressure and no more overheating!

He was also pushing a high compression engine, racing fuel, pulling a heavy grade that required slowing significantly in the corners.

Willie is nowhere near pushing his Buick like that.

 

[EmTee]

10 minutes ago, avgwarhawk said:

...Switching to a gauge with NORMAL in the area for the gauge arm to sweep solved many unwarranted stops at the garage. For many drivers, if the gauge needle is in the normal section of the gauge then all is normal. Its was a remedy for a problem that only existed in the drivers minds.

 

The ultimate fix was removing the gauge entirely and replacing it with a red light that said 'TEMP' or 'HOT'... 

[avgwarhawk]

2 minutes ago, EmTee said:

 

The ultimate fix was removing the gauge entirely and replacing it with a red light that said 'TEMP' or 'HOT'... 

You are so right. The dummy light sucks. Sucked so bad im my 78 Regal 3.8 overheated to the point of frying a valve. Light never turned on. Gauge changing to complete removal was a mind game. However, the gauges returned with new methods of consistency in cooling.

Edited September 11, 2016 by avgwarhawk (see edit history)

[EmTee]

2 minutes ago, avgwarhawk said:

He was also pushing a high compression engine, racing fuel, pulling a heavy grade that required slowing significantly in the corners.

Willie is nowhere near pushing his Buick like that.

 

 

Yes, but not the point.  If one is to believe what they showed on TV, it was the hood vent installation that allowed for increased airflow through the radiator at speed that solved the overheating issue.

[avgwarhawk]

1 minute ago, EmTee said:

 

Yes, but not the point.  If one is to believe what they showed on TV, it was the hood vent installation that allowed for increased airflow through the radiator at speed that solved the overheating issue.

I understand the venting but point being we are not running our cars like the Falcon. But, I do experience the heat creeping up at highway speeds. I believe this more due to poor air dams around the radiator directing air through the radiator instead of letting it get around the radiator.

[NTX5467]

Trying to get "air out" can then let more "air in".  Not unlike lowering exhaust system restriction and getting more power from increased air flow in the intake manifold passages.  Many modern fwd cars have plastic inner fender liners with louvers on the front of them, just for the expressed desire to have a ready vent for underhood "air".  PLUS possibly also helping the aero flow past the wheel at the same time, decreasing aero drag for increased fuel economy.

 

It was not unusual to see 1967 and later Mustangs with the rear of the hood shimmed to raise it and allow underhood air to allegedly escape.  Usually, many cars had a thin rubber weatherstrip seal on the cowl to seal the rear edge of the closed hood.  Removing that weatherstrip might accomplish something similar?  Usually, though, underhood air "vents" under the car.  One other consideration might also be the narrower engine compartments of many vehicles which were initially architecture for inline engines and then the new V-8s were adapted to it.  Less underhood space for the radiator air to traverse through!  A situation which was not unique to Buick or GM, back then!

 

The "idiot light" sending units still should have had a safety factor in turning on before things really got out of hand.  But usually, it was too far gone by the time the light illuminated (IF noticed).  If the gauge registers a higher reading, still in the "normal zone", then the service person could advise the customer that things were still "normal" until the needle gets toward the "red zone" of the gauge.  I thought it was neat that some 1960s-era cars had a blue indicator light for "cold" and a nearby red light for "hot".  When the "cold" light went out, the heater would work well.  When the "hot" light came on, time to get it looked at.

 

NTX5467.

 

[EmTee]

2 minutes ago, avgwarhawk said:

I understand the venting but point being we are not running our cars like the Falcon. But, I do experience the heat creeping up at highway speeds. I believe this more due to poor air dams around the radiator directing air through the radiator instead of letting it get around the radiator.

 

I was simply speculating (well, guessing, actually...) that maybe at highway speeds air forced through the grill raised the under hood pressure, thereby throttling the amount of airflow ('potato in the tailpipe' effect).  That said, it's more likely in the case of the '55 Buick that the grille configuration is the restriction (as Beemon was attempting to show).  Either way, it seems that a hard-mounted fan can forcibly move the necessary amount of air through the core.

[avgwarhawk]

26 minutes ago, EmTee said:

 

I was simply speculating (well, guessing, actually...) that maybe at highway speeds air forced through the grill raised the under hood pressure, thereby throttling the amount of airflow ('potato in the tailpipe' effect).  That said, it's more likely in the case of the '55 Buick that the grille configuration is the restriction (as Beemon was attempting to show).  Either way, it seems that a hard-mounted fan can forcibly move the necessary amount of air through the core.

I think your speculations hold validity. It might also simply be the engineers cost saving answer to keeping the engine cool. Install a fan that spins constantly resulting in good cooling at all speeds. No shroud making and additional time on the line installing the shroud. Also, was any type of wind tunnel for aerodynamics used at this time for automobile design? Was any study done on turbulence behind the grille and in front of the radiator at speed? I suspect not however these are things I believe aircraft engine manufacturers understood but did not apply the same principles to cars? Some did understand the physics. The Airflow comes to mind.

[NTX5467]

In the absence of wind tunnels for cooling system configuration research, although wind tunnels were in existence when those cars were being developed, there were the several "proving grounds", including one in Arizona for GM.  Air flow TO the radiator was probably verified as the cars neared production, in summer 100+ degree weather. In the absence of temperature probes, seems like there was some special "heat tape" which would act similar to ph paper (exposed to "acid" or "base") when exposed to heat?

 

Seems like there were some differences in how the '55-era Chevy radiators mounted?  For the six-cylinder, the radiator was mounted on the front-size of the radiator core support, with the shorter-engine V-8 radiator being mounted on the back-side of the same radiator support?  In any event, I suspect a wider, but shorter, vertical flow radiator from a '66 Chrysler might be adapted?  The Buick's core support could be modified and the Chrysler radiator comes with mounting flanges on the side for an easy bolt-in modification.  There were some 26" wide 3-row a/c-spec radiators.  Would certainly need to maintain the structural integrity of the radiator core support area!  Do some "whacking", then add some horizontal supports to compensate.  With a higher degree of finesses and execution, it could become "an experimental model"!

 

NTX5467

 

[EmTee]

If someone really wanted to experiment, it would be interesting to compare with and without the stamped grille 'screen' installed.  There must be some restriction introduced there - my '56 Bel Air has the Chevy 'egg crate' grille with larger individual openings.  If it were to run cooler without the grille, it would at least identify that as a contributor.  (What to do about that, if it were true would be a whole other issue..)  I suspect NTX is right, in those days annual styling updates were the norm, so it was usually 'form over function' for body/interior design anyway.  They would use the proving ground tests to validate the final design and begin working on the next style update...

[KAD36]

10 hours ago, EmTee said:

 

Exactly -- that's the same conclusion I came to from Willie's experiment.  For the clutch fan to make sense, there needs to be a situation/scenario where air pushed through the radiator by the forward motion of the car alone provides sufficient flow through the radiator without fan assist. Another thing to consider is that the restriction may be that there isn't sufficient 'exhaust' opportunity for air entering through the grille to exit the engine compartment.  An example is an episode of Fast N' Loud where Aaron Kaufman built a Pike's Peak racer (Ford Falcon) which was overheating on runs up the mountain, despite new high capacity radiator, electric fans/shroud, etc.  Ultimately (as a last resort?) he cut a pair of vents in the hood to relieve the under hood pressure and no more overheating!

 

This is all starting to make more sense.  We're seeing that 100 deg 65 mph air and standard size radiator and grill setup appears to equalize somewhere between 180 and 200 without the full mechanical fan assist.  The radiator and its exposure to the airflow is the limiting factor and without going too nuts can adjust the combinations of fluid type , fluid flow, and airflow.

 

11 hours ago, avgwarhawk said:

 

The fan clutch engages per Willies trials. However the temp is about 10 degrees hotter. It has been said several times the standard clutch spins about 50% of the shaft speed. Logically, cooling with the clutch is half of the standard fan. Installing the heavy duty at 90% shaft speed should cool like the standard fan if the fan pitch is 2 1/2 pitch. The reason Willie is attempting the clutch is to reduce fan noise. Mimicking the standard fan using a heavy duty clutch may not work in reducing noise. However, I believe it will as it did for the ever overheating 455 in my Estate Wagon.

 

Available airflow hitting the clutch thermostat cycles it on/off at 200 and thats a given, then an HD clutch and a B.A. Fan with enough drag (pitch) to ensure the clutch properly disengages seem the most logical options to move air.  Boy I had my hands on a perfect 7 blade fan with a 3 inch pitch and HD clutch from a F150 with AC yesterday that would have worked perfectly driving the car in reverse - note to self - serpentine water pumps spin CCW, v belt water pumps spin CW same as engine.

 

Next experiment will be big CW fan, an HD clutch (that should force more airflow when engaged over 200 deg), water pump and the high flow stat (change the flow).  Thinking thats about as good as shes gonna get without messing with the radiator fluid or a recore and hopefully it should stay 200-210 on the highway all day even when AC is added, Will see if the engine still pegs to H when idling in drive and measure how long it takes to cool with the HD clutch on as a test.  Until then the standard clutch and 6 blade fan is doing the job, its quiet and its proven by test if stuck in hot traffic it will cool the engine down. 

 

If theres not enough 95 deg days left may have to rig something fancy up.

 

When the AC goes in, the bigger fan and clutch should pull more air over the condenser.  I read somewhere, maybe in Buick literature, that adding AC should only raise the operating temp 5-10 deg?.  Maybe will have to turn the idle up closer to 650.  Where do folks with AC cars have their idle speed in Drive set at? 

 

BTW - thanks for making the graphics Beemon - that helped alot.

[old-tank]

Lots of nice theories going here.  But even with the best air flow there are probably other limitations in the 55 cooling system.  In 56 the timing cover and water pump were changed on the 322, eliminating the hoses going to the transmission heat exchanger.  I don't know if the 56 cools better or not.

A 401 timing cover with associated water pump will fit the 322.  A friend did this on his 'personalized' 54 with 322 and claims no engine heating issues in all weather with a/c.

Another problem (contributing to heat load) with all nailheads is the exhaust is routed through the cylinder head vs dumping near the exhaust port like on other engines.  Another engine hard to cool is the Ford flathead that runs the exhaust through the block before exiting.

[KAD36]

Willie - what RPM to you have idle set at in drive with the compressor engaged?

 

 

[old-tank]

Never checked:  just enough extra for better air flow and some charging, but not so much that rpm in park are so high that engine diesels when shut down.

[Beemon]

16 hours ago, avgwarhawk said:

 

The fan clutch engages per Willies trials. However the temp is about 10 degrees hotter. It has been said several times the standard clutch spins about 50% of the shaft speed. Logically, cooling with the clutch is half of the standard fan. Installing the heavy duty at 90% shaft speed should cool like the standard fan if the fan pitch is 2 1/2 pitch. The reason Willie is attempting the clutch is to reduce fan noise. Mimicking the standard fan using a heavy duty clutch may not work in reducing noise. However, I believe it will as it did for the ever overheating 455 in my Estate Wagon.

 

My mistake of I claimed it hadn't, but I thought Willie posted that the clutch didn't engage until 200 degree heat. My whole point I was trying to make was that the clutch may not be getting hot enough to engage earlier because of where the clutch would be in relationship to the grill and the most air flow going under the clutch. Sorry for confusion.

 

 

[avgwarhawk]

16 minutes ago, Beemon said:

 

My mistake of I claimed it hadn't, but I thought Willie posted that the clutch didn't engage until 200 degree heat. My whole point I was trying to make was that the clutch may not be getting hot enough to engage earlier because of where the clutch would be in relationship to the grill and the most air flow going under the clutch. Sorry for confusion.

 

 

I completely understood what you are thinking concerning air flow and the heat from the radiator hitting the coil on the clutch. Looks like sound logic to me and quite possibly the issue and I'll explain why. As speed increases it appears air flow decreases through the core of the radiator(poor air dams) thus robbing the heat needed to activate the fan clutch. Lets think about it. The standard fan is running high rpm at the higher speeds thus pulling air through the core that would not be pulled through if the fan was free wheeling, static or only spinning at 50% of the shaft speed.

Edited September 11, 2016 by avgwarhawk (see edit history)

[EmTee]

12 hours ago, KAD36 said:

This is all starting to make more sense.  We're seeing that 100 deg 65 mph air and standard size radiator and grill setup appears to equalize somewhere between 180 and 200 without the full mechanical fan assist.  The radiator and its exposure to the airflow is the limiting factor and without going too nuts can adjust the combinations of fluid type , fluid flow, and airflow.

 

Ken, I was thinking that maybe some of these placed strategically on the radiator core and/or fan hub might help identify hot spots (i.e., areas of low airflow). For example, the "TL-5-190-30" is 30 bucks for 30 stickers...

http://www.omega.com/pptst/TL-5.html

[NTX5467]

Thanks for that link to the "heat stickers"!  In the FourSeasons catalog, it mentions the differences in the normal and HD fan clutches.  PLUS that both start engaging at 170 degrees. 

 

I suspect the space between the front bumper and the core support is open?  If so, then some sort of "scoop" could be configured to add that air to the air forced through the grille.  Many modern cars have had plastic shields which effectively block that area off to air flow, to isolate the "grille air" and the "undercar air".  Some eras of Corvettes were strictly "bottom breathers" with NO air from the front of the car as there was no grille.  It would be easy to make a short air dam for under the radiator, to help build a low pressure area behind the radiator when the vehicle is moving.  Also, an upper seal could be configured, hopefully, to better seal the space between the hood and the core support/radiator.  Some other items could be used to decrease the gaps between the radiator and the core support.  Getting more air through the radiator rather than allowing some to "bleed-off" around the radiator.

 

An alternative to the air dams might be to drop the front end of the car about 1 inch, relative to the rear of the car.  Would not work for all people, though.

 

We'll get this deal whooped, sooner or later!

 

NTX5467

[Ttotired]

You know, with the 200,000 words already posted on this subject, has anyone thought that the best thing to do is fix the actual problem instead of theorizing on 50 band aid fixes?

If the car needs a fan to not overheat at highway speeds, something is wrong.

The car would have been able to do it once, why not now?

 

 

[old-tank]

2 minutes ago, Ttotired said:

You know, with the 200,000 words already posted on this subject, has anyone thought that the best thing to do is fix the actual problem instead of theorizing on 50 band aid fixes?

If the car needs a fan to not overheat at highway speeds, something is wrong.

The car would have been able to do it once, why not now?

 

 

With a fixed blade fan it does not overheat on the road.  I tried the clutch fan conversion to reduce noise, engine drag and maybe improve congested driving performance.  Since that failed on this car I will drive carefully with the old technology.

I do know how to make a nailhead run cool in all situations:  install into a 1951 F-1 truck, put a radiator from a 1960 Metro van in front (50% more surface area and 4 rows of tubes), install a puny 2000 cfm fan and the temp stays at 180* at all times.

[Ttotired]

Perhaps, a noise reduction solution is more whats needed?

Something like dynamat and hood insulation

In my part of the world, an overheating engine is a fairly common thing to see, but I dont see a lot

of cars running around with home made air dams and funnels all over the place

 

Sorry, just looked like the whole page was suffering its own thermal runaway problem

 

 

[NTX5467]

Respectfully, DynaMat and/or hood insulation will NOT fix a noise problem, just attenuate the sound heard in the passenger compartment with the hood down and the windows and vents closed. ( NOT to forget the spray-on LizardSkin ceramic sound attenuation coating!)  Similar to taking a "pain pill" and not addressing WHY the pain happened.

 

Adding hood insulation to a vehicle that did not come with it OEM can come to look "not good" as it ages.  Whether with highly-finessed air dams or ducting to get more air TO the radiator, there should be something that will not look "added-on" and still help achieve getting more air through the radiator at highway speeds.

 

Perhaps if the grille texture is perceived to be too restrictive, something akin to what's on current/recent GMC pickups could be used?

 

NTX5467