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1955 Engine Rebuild


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Another question I have with the home made engine stand is what will provide the load for the engine?  The engine will need to run at a high idle speed to break in the camshaft and without proper load it can easily overspeed.  If a dyno session is out of the question, I agree with JohnD and think it's best to bolt in into the car.  In any case, definitely pull the plugs, prime the pump with a drill and spin it over as Old-Tank suggests.  I'm less fond of starting it dry, simply because if it sounds good I'd want to get it spinning fast and keep it there until the cam is fully broken-in before shutting it down.  Also ensure you are using a high quality break-in oil with higher levels of ZDDP (e.g., Comp Cams).

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Thanks for the inputs - sounds like dropping into the car is the way to go.  We're pretty confident its together right.

 

Decided to use the adjustable push rods as the lifter preload was .080 which although a little high might have worked out but as long as the pushrods were here, what the heck. Followed the steps outlined in this article:

 

http://www.enginebuildermag.com/2011/06/getting-to-the-bottom-of-hydraulic-lifter-preload/

 

Went about 1 turn on the rods which corresponded to .030 of preload and we were done (threads were 32TPI)

 

We ended up going with the low compression gaskets that should be .048 compressed thickness.  We had less than .100 piston to valve clearance with 2 steel gaskets (.030 total thickness for measurement purposes only), and probably could have went with a .015 steel gasket for final assembly but figured better to be safe than sorry.  We had .020 milled off the heads, and Ed was certain there was at least .010 taken off the heads, if not more, some previous time.  The .020 we milled off just about compensates for the thicker head gasket (.048 LC gasket thickness - .020 = .028 head gasket thickness vs .015 stock HC head gasket thickness).  

 

The engine is unloaded and is on the stand in the garage.  Am going to finish bolting the accessories on then run the compression test on the stand and make sure the pieces are working and get it painted. We made up a fixture to fit in the distributor pocket to engage the oil pump and prime the engine. Have the ZZDP also.

 

Time to hustle. On budget and behind schedule :)

 

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Well, not quite an "Overhaulin" marathon but a couple long days and late nights.  Got everything painted last night, finished tapping out the remainder of the holes in the block.  Had to replace the 4 small bolts in the water pump and one in the water manifold.  Darn near snapped one.  The harmonic balancer bolt was a white knuckle affair going from 85 to 104 ft-lbs - jeese thought it was going to snap but it got there. Noted that the CARS Apple green of 10 years ago is a deeper green than todays.  I didn't paint the valve covers - they were in good shape and I just buffed and waxed them.  Wrestled with the stupid Harbor Freight touch up gun - worked great on the block and the oil pan but started spitting and put orange peel all over the valley pan.  Funny how little simple things cost time and slow progress.  If thats the worst that goes wrong this will be a home run.

 

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Here are the light weight aluminum racing valve covers that Willie was drooling over.  These are extremely sought after, will fit all Buick nailheads and no two valve covers are alike.  These are only available in 2016 and when they're gone, they're gone.  They come with a jar of Vegemite and an acetylene torch to seal them up as no known manufacturers traditional gaskets will work.

 

The real point of the picture is test fitting the Y pipe from M&J exhaust before hanging the engine over the car, and it fits perfect.  Perfect.  Did I mention perfect? The old bent up squished down one from an out of business supplier might find a future as a wind chime hanging from the tree that was used to help "make it fit". (since it was supposed to fit a 55 Buick also despite much arguing)

 

Drizzled more assembly lube on all the rocker shafts and under the rocker arms and the cam lobes.  Ed whipped up a Nailhead only fixture to prime the engine, I cheaped out and didn't buy an oil pressure gauge, just put a 1/8 in pipe plug in the oil line hole and received two demerits so its off the buy a gauge tomorrow.  2500 RPM Clockwise (you have a 50.50 chance of getting it right) and after about 20 seconds all kinds of spitting and hissing and up from the pan comes the bubblin crude.  Do that for about 3-4 minutes and the drill gets freakin hot - there is a bit of a load on it.  Got a little nervous as the rear rockers dripped then stopped, but after sliding them a little back and forth on the shafts they started dripping from between the shaft and the rocker arm and from where the pushrod meets the rocker.  Apparently nothing comes out the bleed hole in the rocker unless its running.  All the cam bearings looked wet, the center oil galley is feeding the cam bearings, and oil is bubbling in the lifter bores around all the lifters, and the garage floor was bone dry.  So far so good.

 

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Tomorrow is oil pressure, potential compression tests, engine compartment work and pulling the old exhaust system out and installing the new one.  The exhaust is another "first time trial" that could trip things up. Better save the old pipes just in case.

 

 

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TIm - two risks retired today - TCPI .92    We should have our heads examined. :)

 

 

 

 

 

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Thanks for the support - been a couple long days and too pooped to post!  Summary of where we are at:

 

Couple of setbacks - The engine mounts from CARS did not fit.  They are .080 too narrow on the installation studs, and when "modified" so they could fit, instead of the ears pointing at the 12 and 6 oclock positions like factory they pointed inwards at a 1 to 7 oclock position on the driver side, and 11 to 5 oclock position on the passenger side.  They were correctly installed left and right - simple could not get them to line up to the engine block brackets.  I had to put the old mounts back in - heres factory followed by the ones from CARS:

 

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A flywheel to toque converter bolt got stripped out and had to drill that puppy out. And had to carefully remove the old exhaust in case it needed to be reused.  Note all the beat marks in the old system to make it fit:

 

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The oil pressure was solid:

 

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This is always a high risk maneuver - had about an inch clearance from the top of the cherry picker to the garage door:

 

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Some 2 inch bolts with the heads cut off served as guide pins and keeps any leverage weight off the hub on the torque converter:

 

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The engine would not go the final 1/4 inch no way no how which ironically seemed to be the exact thickness of the heads on the torque converter bolts.  Doh!  Line up the holes, goofball.  A dab of paint on the flywheel at disassembly matched to a corresponding paint dab on the torque converterhelped to line up the holes perfectly.  A little Vegemite on the the bolts and the engine and bell housing jumped together with no effort.

 

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Back in the saddle:

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The new exhaust fit perfectly.  I left the Y pipes in the car and the engine and manifolds were set in on top.  The system was left loose all the way back to allow for some final adjustment.  I need to weld a hanger on the frame to hang the front of the muffler to.  That and buttoning up the under car work is todays job, then its engine compartment work.  Before putting the engine in the distributor shaft and oil pump shaft were aligned and noted where true TDC on #1 cylinder was so that after spinning the engine to get the flywheel bolts on would not loose the true TDC position (prevent the distributor from being 180 degrees out).  The distributor prior to removal was marked at the 6 and 12 o clock positions on the distributor housing to align in a straight line with the valley pan bolts, another mark to initially align the rotor prior to dropping in the distributor, and a final rotor alignment mark so that when the distributor is fully inserted and the rotor rotates to follow the helical cam gear it will point to the correct #1 plug in the cap. That should be good enough to start it. If things go well today and tomorrow should have light off..... well, soon. 

 

 

Edited by KAD36 (see edit history)
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Got done getting everything installed late last night.  Figured that if any problems came up, the car was going to be grounded for the summer, so might as well fill it with antifreeze, put everything on and act like it will work.  After double checking and triple checking the pre-start list, and cranking it with the coil wire off to make sure it spun evenly and there were no knocking sounds, and one last "thats everything, right?" call to Old Tank and JD1956 - there was nothing more to do but grab a fire extinguisher, hit the electric pump to prime it, set it on the fast idle cam, kick the tires, light the fires, and....

 

Nothing. Whoops - coil wire.

 

Take 2 -  hardly a full rotation on the starter and it roared to life.  And man what a racket.  Having replaced the lifters once and expecting some clacking, I was not prepared at all for the racket and whirring and what sounded like gear noises that engine made.  I shut it down after 15 seconds it was so obnoxious, and fired it again.  No better.  30 seconds later, turned it off again. Walked around, checked for leaks,checked the oil, topped off the radiator, tried to make sense out of all the fumes coming out of it, which was probably just the paint, hit the switch again and it cranked slow and uneven and then started back up.  Figured if it was gonna blow it was gonna blow.  This time just let it run, kept walking around, checking gauges, looking underneath, watching the exhaust for smoke or steam, topping off the radiator.  It was over 5 minutes until things quieted down, and at the end of 30 minutes at about 1800 RPM it idled quietly down to about  600 RPM.  The hard cranking was explained by the timing being too far advanced - probably 10-15 degrees judging by the timing light.  Got it back to about 7 deg, reset the mixture, checked the dwell which was at 29 deg, and vaccuum fairly steady at 16 inches.

 

Have 25 miles on it so far, and its getting smoother.  Only observation is it is running a little hotter than prior to the rebuild but still within a "normal" range.  Oil pressure is a little lower than prior also, but I used to run 15-40 Rotella with a bottle of STP in it and this is 10-30 Castrol with only ZZDP in it which does nothing for viscosity.  JD noted there was 45 psi on the gauge run by the drill so let it run. Only leak so far is a minor exhaust leak under heavy load on the passenger manifold - dry at the front and rear bearings.  Will post a video shortly. Tomorrow it gets inspected then will try to get about 1000 miles on it before taking it on the trip.  If its still a clean bill of health, its off to Allentown.

 

I wanted to say thank you to all who helped share their experience, encouragement, answered phones and texts and shared "lessons learned" and war stories from their school of hard knocks.  Will try to get all my notes organized for future reference and keep updated on any observations during break in.

 

 

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Edited by KAD36 (see edit history)
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Awesome job -- I've been away and just catching up on the 'saga'.  I was feeling queasy while reading your account of the initial start-up sequence; I absolutely understand the worry with all of that racket, the smoke, vibrations and smells of burning oil and paint...  :huh:  Sounds like she's turned the corner now and should perform better and better as miles go by.  Thanks for all of the detailed notes and pictures -- I learned a few new things that will undoubtedly help me in the future!  Hope all goes (went) well in Allentown!

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16 hours ago, buick5563 said:

I can't wait to race the car.

 

If we can find 4 miles of open straight road we can do the 0-100-0 test like the Corvettes.  Mine will need every inch of asphalt. :)

 

125 miles on the clock, holding up well, only an exhaust leak.  We had gone without gaskets on the exhaust manifolds as stock and run them on the belt sander to smooth them out but now realize it would have been smarter to have gotten them machined flat.  A thin coat of copper permatex wasnt enough to seal it but installing the manifold gaskets that came with the kit did.  Now there is only a slight leak where the Y pipe meets the manifold so will need to deal with that and I hate exhaust leaks. I took it over to Eds shop yesterday for a victory lap.  He had rebuilt a couple 401s a long time ago, this was his first 322.  He was impressed with how quiet and smooth it sounded.  We hit it with an infrared temp gauge and a little above N on the dash gauge is 187 which he thought was just fine given the friction of a tight engine (and it was 95 outside).  After an afternoon of around town traffic to vary the engine speed, took it out on I84 and put about 15 miles on it - again varying speed between 50-65 to keep with traffic.

 

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On 7/15/2016 at 8:15 PM, KAD36 said:

and vaccuum fairly steady at 16 inches.

 

Please excuse my ignorance, but is this normal? I'm just curious because I'm used to being told 18-22" of manifold vacuum is normal, but I can never get it above 16-17 unless it's an off day.

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16 is about all I get on any of mine, even one with an original unmolested engine.  16 is real good on Ken's car considering the "franken-cam" and the 1:6 rockers.  That will be adequate to run the wipers along with the fuel pump vacuum assist, and even power brakes if equipped.  Another reading in 3000 miles will be interesting along with rotating the distributor to find the maximum reading.

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Good question - 56 product school manual page 8 - never found the specs for a 55.

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Just did first oil change at 300 miles.  Still have a slight exhaust click on the driver side - will get to that this weekend.  May put a gauge on the oil pressure - after a long hot highway drive it gets pretty low on the gauge at idle.  Otherwise, so far so good.

Edited by KAD36 (see edit history)
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  • 2 weeks later...

Looking forward to the post-Allentown 'hotwash'.  Last word was nearly 1000 miles and no issues; I hope that the post trip inspection is just as uneventful!  ;)

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1500 miles and no major issues.  Unfortunately, some emergency events at home necessitated an early departure from Allentown and had to come back Thursday night - everything worked out ok.  It poured buckets all the way back up the Turnpike and got back to Binghamton about 1 am - thank goodness for RainX helping those vacuum wipers out.

 

A couple of teething problems from the trip:

 

- The exhaust manifold bolts loosened up - thought a manifold cracked but it was just the last 4 bolts on the manifold and had to snug them back up.  My preference is no manifold gaskets but have gone both with and without them with no issues - typically with gaskets go finger tight on the bolts then 1/4 turn more and thats enough to quiet things down.

- Got to take Willie for a Victory Lap up the highway on the way back from dinner and heard a couple uncermoneous klunks which turned out to be the sway bar bushings.  Whew.

- The car ran really hot in Allentown sitting in D in traffic - pegged the needle and high idle in N barely brought it down.  I changed out the thermostat and did a post tune up when I got home.

- Set the ignition timing with a vac gauge instead of a tach and light since the factory timing is probably less relevant with a newer camshaft that has more lift and longer duration than stock.  With the engine at 400 rpm, vac advance disconnected and the engine at a shaky 14 in of manifold vac as such a low RPM, the distributor was advanced until a max vac reading of 18 inches was achieved.  Advancing beyond that did not change the reading.  Retarded the timing to reduce 2 inches of vac (vs 1 inch guideline) just to be safe and not grenade the engine under load with too much advance.  Checking with the timing light estimated about 10-11 deg of initial advance.  I used to run it at 7 deg - anyone foresee any issues with this please weigh in. Experienced no driveability complaints (detonation, dieseling, or hard starting) The initial timing setting could probably be advanced a little further, but not knowing the total advance on the engine and don't want to exceed the factory high end limit of 53 deg total (inital+vac +mech).  I'm assuming the mech and vac advances are on the low end of the production curve limits (they both work) since adding 5 deg of initial timing didn't generate any bad results.  May invest in an advance timing light and plot the curve over an rpm range. 

- Set the idle back to 650 in N (which yields 525 in D on this car) and was at about 17 in vac.  Turned the mixture screws in then out out until max vac was reached which was about 17.75 inches.  The idle crept up to 700 and turned it back down to 650 and buttoned it up.  The whole fine tuning operation yielded about 1.25 in more vac (17.75 in) than the original measurement just after first start up.  The needle fluctuates less than +/- .5 inches.

 

The last thing to recheck after a few thousand more miles will be final compression ratio.  The initial test at 500 miles on a cold engine was about 120-125 lbs,  All the cylinders were within 5 lbs or less which was great - this test was primarily to make sure there was consistent pressure across all cylinders before taking the engine further.  I was hoping for more like 130-140 psi - maybe more miles when the rings seat better and on a hot engine the results will improve.

 

After the tune up, the idle is waaay smoother (the radio antenna doesn't shake when fully extended), it runs cooler, the off idle bog is negligible and fully eliminated if the electric pump is on while sitting at hot idle for extended periods or a long light, the part throttle bog is gone, and when you put your foot into it, even half throttle, throttle response is improved with no pinging anywhere in the rpm range under any load.  The car is starting to pull good and had no overheating issues today.  Got 16 mpg on the round trip to Allentown, used no oil and its running great!  Sights are set on Wisconsin next year!

 

 

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  • 1 year later...

Thought it might be helpful to post a followup

 

Engine has almost 3800 miles on it an no major issues.  Rear main seal remains dry.  Vacuum is up to 18 inches steady at idle of 550 RPM.  The engine will idle down to 425 if I let it - first time it has ever done that. And it continues to run smoother and quieter the more it is used.

 

Oil choice remains Castrol 20W-50.  I have a few bottles of ZDDP left and have been adding that until supply runs out.  Have changed the oil at 1500 mile intervals, cutting open the filter and finding no signs of shiny metal or excessive grey matter in the filter.  Very very minimal fumes coming out of the breather cap.  The engine idles really quiet and is a pleasure to just listen to.  Adjustable push rods were worth it.  Pretty nerdy, huh.

 

Cold cranking compression is rather disappointing at 125 psi per cylinder and theory did not follow practive, all plugs out, throttle wide open, battery fully charged.  There is only a few lbs of difference between cylinders.  The low compression may be due to camshaft profile and valve overlap, and am not wanting to go back into all the complexities of valve timing other than research showed that cam profiles affect static compression measurements.  Am glad a few thousandths were shaved from the heads or it would be lower.  I had hoped for 145-150 psi, but the car is pretty peppy especially if the switch pitch kicks in, accelerates well from a standing stop in Drive to overtake traffic and does not ping on 87 octane with timing set at approx 10 degrees (using a vac gauge to get highest reading then backing off 1-2 inches vac).

 

Oil consumption seems to have gone up to half quart every couple hundred miles, and upon inspection for leaks found the following:

 

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Vacuum pump diaphram was torn badly, whole bottom half of fuel pump was soaked in oil - about an ounce or so in it.  Am hoping that was the source of the consumption.  Sent  the pump and my spare off to Then and Now for a rebuild.  Having fiddled with this twice and rebuilding  them myself, chose to let someone else fiddle.  They were done and returned in less than a week.  Only other oil spot visible is near the oil pan:

 

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Another observation is when the car is at normal operating temp (185-190), and oil good and wamed up so its thinned out and with engine on a fast idle in (2000 rpms), after about a minute on fast idle a very very slight really-have--to-look-to-see-it blue tint can be seen in the exhaust.  When driving and flooring the throttle, or long coasts down a hill, or even at night with another cars headlights in the rear view mirror to be able to peer into, there is no sign of visible exhaust or smoke.  I'm assuming this light tint might be the valve guides leaking oil past the intake valve stems.  With the 401 factory rockers in there, anticipate there is oil spraying all over the place.  I was going back through some rebuild photos to ensure the rocker shafts were positioned with the notch down but cant find that detail, however I am 99% confident they are installed correctly, having paid attention to that in past valve service efforts.  I don't intent to pull the valve covers off to check - I tried and they are stuck on there good - will ruin the gaskets if I pry them off. The Autolite copper plugs look pretty good so am going to just keep running with it and continue written record to see what happens:

 

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Somewhere there is a thread on Diamondback tires - put a set on this summer.   See you there.... :)

 

 

Edited by KAD36 (see edit history)
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It is quite possible the oil in the vacuum portion of the pump is getting into the cylinders thus producing the light blue tint of smoke.   Hopefully that is your oil consumption issue.     Your plugs look good.   

 

Yes, it is a pleasure to hear an engine run that you have worked on. :)

Edited by avgwarhawk (see edit history)
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9 hours ago, avgwarhawk said:

It is quite possible the oil in the vacuum portion of the pump is getting into the cylinders thus producing the light blue tint of smoke.   Hopefully that is your oil consumption issue.     Your plugs look good.   

 

Yes, it is a pleasure to hear an engine run that you have worked on. :)

 

Thanks for the vote of confidence on the plugs

 

I hope the pump was the oil issue.  The product service manual points the vac diaphragm out as a source of oil consumption.  Paid so much freakin attention to putting it together right would agitate me if that rocker shaft was right side down.  

 

Or maybe that was always the plan to make sure the valve stems stayed lubricated.  Yeah that's it.  ?

Edited by KAD36 (see edit history)
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12 hours ago, KAD36 said:

 

Thanks for the vote of confidence on the plugs

 

I hope the pump was the oil issue.  The product service manual points the vac diaphragm out as a source of oil consumption.  Paid so much freakin attention to putting it together right would agitate me if that rocker shaft was right side down.  

 

Or maybe that was always the plan to make sure the valve stems stayed lubricated.  Yeah that's it.  ?

 

My 264 in the 54 was rebuild(half-butt) previously to my  ownership.  I found the rocker shafts were installed upside down.  The heads had hard seats installed that subsequently failed.  The fuel pump was leaking oil into the vacuum portion of the pump.  In short, just a mess.   At that time while driving the car it would suck up 1/2 quart of oil in 200 miles of driving.  Eventually started blowing blue all the time as a result of the failed seat in the head.  I guess many if not all think a block needs to be rebuilt just as a Chevy would be rebuilt.   Anyway,  I replaced the pump, corrected the rocker shafts, pulled the heads for a new set, replaced the rings, honed the cylinders and replaced the lifters. I did all of this in my garage with block still in the Buick.  I drove the car about 800 miles for the rings to seat, etc.  I was satisfied at that time all was good and parked the car.  So..... this summer my wife and I drove the Buick up to and around the Allegheny mountains.  It was a 300 mile trip in a day.  The 264 did not burn a drop of oil.   But a plug wire fell off on the way home.  Can't win them all.      

 

I would say once your pump is oil free in the vacuum portion your oil consumption should diminish quite a bit.   One other item, since the valve stems have no seal as you know, my 264 blows a buff of blue at start up.  From my understanding, this is normal.    After that the tailpipe is clear. 

 

Nice work on your rebuild!       

Edited by avgwarhawk (see edit history)
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Chris - you mean those French lock things?  My originals were way tired and I blew it off.  The bolts are just snugged at like 5-8 ft lbs on the gaskets with a skim of sealant.  Suppose I should get a set huh

 

I'll video mine next time I have it running and post here. Think I remember seeing your video and mine wasnt as prominent at the tailpipe.  Seems to do it more when hot.

 

My only complaint on the exhaust having the 56 on the 55, and not having the original support that comes off the dynaflow, is it sagged after awhile and rubbed the frame. I welded a crosspiece to the top of the frame and fabricated a hanger.  Be curious to see what a correct front and rear hanger assy looks like.

 

Goes for new seat upholstery on 12/2.  That will be a different thread

Edited by KAD36 (see edit history)
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Yes sir.  The French locks.  Very inexpensive.    Easy to install since the manifold bolts  were out not long ago.   Plus, it helps with having the look of a complete motor.   

 

Concerning my video of the nasty smoke, that was from the failed hard seat in the head that failed.    Never did see much smoke from the oil that was seeping into the vacuum portion of the fuel pump.  All the same, she ate the oil as a result.   

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Roger that.  

 

I watched your video pre-rotating the rocker shaft and mine is nothing like that - can't see anything.  Did you ever notice what your plugs looked like when it was burning that amount of oil down the valve stems?  Glad you got that fixed.  

 

Monitoring oil use with new fuel pump. Will report out after a couple hundred miles. 

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On 11/22/2017 at 7:00 PM, KAD36 said:

Chris - you mean those French lock things?  My originals were way tired and I blew it off.  The bolts are just snugged at like 5-8 ft lbs on the gaskets with a skim of sealant.  Suppose I should get a set huh

 

I'll video mine next time I have it running and post here. Think I remember seeing your video and mine wasnt as prominent at the tailpipe.  Seems to do it more when hot.

 

My only complaint on the exhaust having the 56 on the 55, and not having the original support that comes off the dynaflow, is it sagged after awhile and rubbed the frame. I welded a crosspiece to the top of the frame and fabricated a hanger.  Be curious to see what a correct front and rear hanger assy looks like.

 

Goes for new seat upholstery on 12/2.  That will be a different thread

Go to www.centervilleautorepair.com and look under the link for Tech Tips for the 15 most common mistakes.  Read #14.  "Don't use gaskets between the exhaust manifolds and the heads."

 

Ed

 

PS - It appears that the link doesn't take you to the website. Type the address in your URL.

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I mean that could do both ways. Cast iron flexes under heat. Being mated to the block limits expansion. After 60 years, they could be warped by now and unless resurfaced, mating warped exhaust manifolds to a rigid surface will surely lead to a crack eventuality. Soft gaskets would allow them to naturally flex against the block, and take up any minor irregularity. Others argue that by allowing to flex is what cracks the manifold, but the flexing is a natural occurrence and isn't an abnormal process. 

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Buick designed the exhaust manifolds to also act as a heat sink to pull heat out of the heads.  Gaskets keep the heat in the heads.  Gaskets are what expand and contract with heat.  If the manifolds aren't snug against the head, they'll warp and the gaskets expanding and contracting lead to leaks.  Just putting it back together the way it came from the factory makes the most sense.  Gaskets are only necessary if you're running headers.

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The manifolds being a heat sink itself doesn't sound reasonable. Both the head and manifold are made from cast iron, their heat capacities are the same so heat transfer would be very minimal, especially considering the exhaust manifolds are hotter than the cylinder head it would most likely be the other way around. The water inside the block is the main heat sink, that's why it's there. I just don't see an exhaust manifold that sees 1000 degrees Fahrenheit as an acceptable heat sink for a cylinder head that sees 220 degree Fahrenheit surface temps. Materials science has been around a long time, but it wasn't until we could analyze the grain structure at a microscopic level that engineers really understood what exactly was going on in terms of heat transfer and flex. This, coupled with complex transient flow analysis programs at the turn of the century has given an in depth look at what is actually going on, as opposed to a lot of the theorized and "close" approximations of before.

 

Also I just read through the entire product service manual and shop manual that is pertinent to using exhaust gaskets. No where does it caution not to use them. If it were a huge issue, I would think there would be a caution note at the bottom of the section, as there are in other sections when they advice you not to do things a certain way.

Edited by Beemon (see edit history)
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The important thing to remember with any exhaust manifold, is that it is going to expand more than the head (or block) because the head (or block) is water cooled and the manifold runs MUCH hotter. Since they are made of the same material, the manifold is going to get longer in relation to the block. It will slide. If you do anything to prevent this it will break. The longer the manifold is, the more motion there is.

 

Very thin embossed sheetmetal gaskets as used on many 60s era cars work ok because they do not restrict motion. The same is true for cars designed to run without gaskets.

 

The perforated steel/asbestos/composite gaskets just barely work on engines designed for them, and are a horrible kludge on anything else. You can buy them for almost any engine.

 

You can sometimes get away with murder on a V8 because the manifolds are short, but the same principles apply. Use factory style hardware if possible. Be sure the studs or bolts are not going to restrict lengthwise motion by the manifold, and that there is no soft washer squishing down into a hole out at the end.

 

Edited by Bloo (see edit history)
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I'm putting my faith in Russ Martin at Centerville Auto Repair. He rebuilds nailheads for a living and he says don't use them.  I won't, you do what you think is best for you.

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