I have a heating problem / 1927 Dodge Brother Four Screen

[juanatejeda]

Hello all, hope you all have been well. Got back home today, after a 4th of July Parade in Solvang, CA. Temperatures were in the middle 90's to low 100. Drove our 1927 Dodge Brother Four Screen in the annual fourth of July parade and made it through about 75% of the 3 mile or so route and it began to over heat. My motormeter showed the hogh end of the temperature range and Coolant started overflowing through the overflow.

We haven't done many parades in the past, but have only had one other occasion, that I can remember it overheating. I was able to nurse it to the end. I parked it and let it cool and restarted with no problems and drove it another 1/4 mile to my trailer, with no problems.

My question is this. Anyone out there have the same problems when doing slow, parade like driving? Is it possible to attach an auxiliary electric fan to assist with cooling? Is there room for such a fan?

Any help would be appreciated.

Thanks!

[Pete K.]

Juan, I think the old cars DID have some overheating problems in a HOT day like you describe, going at a slow pace, even way back when. I won't even get into talking radiator condition and rust scale in the block in an 85 yr. old car. I know folks that have spent $1000. on their cooling system and it would still run at the top of the moto-meter scale in a very hot parade. Yes, a cooling fan would help if you could engineer it right. Just make sure you run with the spark advanced properly & idle isn't too fast. At slow speeds, only the fan is doing any cooling, other than the radiator fins that hopefully are all still soldered to the tubes in the core. Once some of the fins break loose from the tubes, heat is not transferred away from the tubes. The engine splash pans are also another step in cooling and act as a partial shroud to channel the air past the engine and out the back. Without them, air is very turbulent in engine compartment from air coming up from under and hot air sits there under the hood.

[MikeC5]

I have been meaning to ask the same question. Also, is it normal (even in more moderate temperatures) for some boiling to occur after the car is shut off? It seems whenever I run it until it is in the 'circle zone' on the moto-meter, upon shut down there will be some gurgling and water coming out of overflow tube. Perhaps I am overfilling the system when cold (and I'm using straight water)? Anyone have any experience with the honeycomb-style core? I thought they might somewhat more efficient from a heat transfer standpoint.

[MikeC5]

I did just install the splash pans but haven't tried it out yet...

[juanatejeda]

Thanks Pete K, makes sense. The radiator is serviced regularly, probably annually at minimum. As I stated, we don't do very many parades, but that seems to be when I notice a heating problem. We would like to do more of them, but if this is a usual problem we may just not do them, especially on hot days. As for the splash pans, I take that to mean the pan that surrounds the engine around the lower part of the engine? If so, then yes, they are all in place. We do use 50/50 coolant. As fo the the Advance, we have secured the lever in a neutral area, as it seems that some of the younger guys just don't understand how or why it works or is there and more times than none were screwing the timing up and couldn't get it to work properly, so we found a good spot and clamped it down. Seems to work fine, but maybe we need to reevaluate for Parade driving???? Now, just to make sure I have it right, to Advance, you push the lever up, to retard, you bring it down. A neutral, start up, area is about 1/4" up from the bottom limit?

Would like to install an electric fan to assist in cooling, if we can find one that will work.

Thanks!

[Pete K.]

Juan, Splash pans are important for cooling and electrical bonding for engine ground. They also keep boulders out of your carb's intake. Tests have shown that straight water is a better heat transfer than a mixture of water/antifreeze in our old cars. Removing your hood is one way to let out the high heat while going very slow in a parade only. I wouldn't clamp down the advance lever at any time. Refer to your owner's manual for the '27 for adv./ retard positions, as it may be different than my '25. Never start the engine unless you're in FULL retard pos. Engine very well may kick back and damage will occur to your Bendix drive or your starter armature shaft will bend, or both. Follow the manual's instructions to the letter. Happy motoring!, Pete.

[Pete K.]

Mike, as for temp increase after shutting down, yes, temp goes up for a short bit then starts cooling off. It sounds to me you're at the border line of a cooling system problem. I can think of a dozen things right off the top of my head about this situation. Timing, operator driving habits on hot days, too much spark retard, rust/crud in back of block and/or radiator, collapsed hose, rusted away water pump impeller, loose belt, wrong coolant mixtures, grease in system, It really boils down, (ha!, good pun here), to the "radiator" in most situations I've found. I've seen cracked overflow tubes, top tank water deflector missing or bent up, tubes partially clogged, bad cap/gasket and frequently, fins broken loose from the tubes in the core. That seems to be the leading cause. Not enough heat transfer by the radiator core itself.

Most old cars have a water level that will find itself, by burping out more than it will tolerate, IF everything is known to be in good shape. Usually the level is right at the top tank water deflector. Mike, I see you say your '25 has a honeycomb core? I have not seen this on a '25 Dodge before. I have the straight tube/fins core and spare Dodge cores with straight tubes. I know General Motor's cars in that era and later on used honeycomb cores along with some others. Could it be an early re-core? They ARE good cores, but fragile as they are, they cannot be rodded out as the water path through them zig-zags. At least you need not worry about broken loose fins from the tubes!

[juanatejeda]

Juan, Splash pans are important for cooling and electrical bonding for engine ground. They also keep boulders out of your carb's intake. Tests have shown that straight water is a better heat transfer than a mixture of water/antifreeze in our old cars. Removing your hood is one way to let out the high heat while going very slow in a parade only. I wouldn't clamp down the advance lever at any time. Refer to your owner's manual for the '27 for adv./ retard positions, as it may be different than my '25. Never start the engine unless you're in FULL retard pos. Engine very well may kick back and damage will occur to your Bendix drive or your starter armature shaft will bend, or both. Follow the manual's instructions to the letter. Happy motoring!, Pete.

Again, thanks for the info. I will talk it over with our County Services Garage, they help out by servicing our old Dodge and are the ones that clamped down the Advance/Retard. I never have problems starting or running the engine, other than the over heating during slow drives, but what you say makes sense.

Thanks again for the info. Anything else you might be able to offer will be appreciated.

[Guest 1930]

Straight water better for cooling? Thats a new one on me

[Grimy]

Straight water better for cooling? Thats a new one on me

Straight [plain] water has a better heat transfer capability than an antifreeze mix--meaning that it transfers more engine heat to the plain-water coolant, but that's not the whole story. Antifreeze will boost the boiling point. What we really care about is avoiding boiling.

Unpressurized systems will run hotter in parade service. I was running hot in a parade yesterday at ambient temperature of almost 90 degrees but thankfully didn't boil. I'd made the mistake of keeping the spark too far retarded (I use full advance only over 35 mph). If you're on level ground, try to elevate the rpms when you can, so that the fan moves faster.

[juanatejeda]

@Grimy

Thanks, I try and do that when I'm in the parades, idle up a little to keep the fan turning faster, but this time I guess it was just too hot. I was in Solvang (Santa Ynez Valley) and it was probably in the mid to high 90's. Did OK till I got to a slight up hill climb and it was very slight. I was surprised that it over heated, since it was doing well. The crowd kinda liked the fact that the old Paddy Wagon was missing and back firing, a few even came out and helped get me to the end of the parade route (about half-a-block). As soon as it cooled down, it did just fine.

Now for my follow-up question, has anyone found an electric fan that will fit in the small space between the radiator and the fan? I'm hoping that this will solve the problem.

[juanatejeda]

Straight water better for cooling? Thats a new one on me

Was to me too, always thought that Anti freeze was to help with over heating. I know it works for keeping the water from freezing, but I though it kept it from boiling also.

[Guest 1930]

Was to me too, always thought that Anti freeze was to help with over heating. I know it works for keeping the water from freezing, but I though it kept it from boiling also.

Something to think about is what that straight water is going to do to the inside of the block/water passages over time, they will become fouled with crud and then a no flow situation in my experience, other scenarios exist as well in my opinion.

[Grimy]

"Straight water," to me, means no antifreeze. It does NOT mean no anti-corrosion additives. In unpressurized systems I use Pencool 3000 or NAPA-Cool. Hastings makes a similar product called Hastings Cool, but on their website it says that this is only for pressurized systems. Wix Cool is similar to NAPA-Cool and may be the same as NAPA Cool, since NAPA carried the Wix filter product line repackaged in its own NAPA boxes. In UNpressurized systems, we need an anti-corrosion additive which will not foam under unpressurized conditions.

If one must use antifreeze due to climatic conditions in unpressurized systems, it's best to use green antifreeze labeled as "low silicate" to will reduce foaming. Regular antifreeze foams in unpressurized systems, especially at road speed. Due to the foam, coolant entering the radiator top tank is displaced and pushed out the overflow. In some cases, that overflow can even create a siphon effect to suck more coolant out of the system.

[MikeC5]

Interesting stuff guys. I should have clarified that I never leave the plain water in there for more than a weekend. When I had the head off last year I really spent some time loosening up and removing rust and crud from the block water jackets and when I drain the system it comes out very clean. I really haven't run it enough to know what 'normal' is yet. I may try an anti-freeze/boil mixture to see if that helps with the after-boil. I don't doubt the honeycomb was a re-core done back in the day. Water seems to flow through it quite readily but I ave seen no specs for what flow rate should be. Has anyone tried to quantify it? As for the advance, I need to check the operator's manual again but I thought it said "retard spark fully to start then move to full advance once running" I didn't get the impression one didn't need to fiddle with it much once you got it going. I'm pretty sure I got the static timing correct but it wouldn't hurt to double check. Near as I could tell the distrubutor advance springs were in decent shape..

[Pete K.]

Pure water won't lead to any build up of "crud" unless you already have a cruddy cooling system. It will lead to rusting tho'. I run water with 6 oz. of Bar's brand water pump lube/anti-rust all season long with no issues. It was 97 degrees in the shade here today and I had no overheating or burping out water from the overflow either in my '31 Model A pick-up. I have a new core from Berg's Radiator and a good water pump. I didn't overheat with the original 82 year old radiator, but I was on borrowed time with that poor thing. In really cold weather I drain half out and add Sierra antifreeze which won't foam. I drive it all year long. I don't hold any belief in the radiator flow test using the rubber ball stuck in the outlet pipe trick. it is total bunk.

[juanatejeda]

I would still like to hear from someone that has tried an electric fan. Need to know where you purchased it, is it 6 volt and does it fit in the space between the fan assembly and the radiator?

I am thinking that a couple of smaller fans, mounted in the corners of the radiator might do the trick. Anyone out there tried a fan?

[Dwight Romberger]

I am not a cooling expert (although I am pretty cool:cool:), but if you think you might be able to fit an electric fan between the fan blade and the radiator, you need to move your fan closer to the radiator. The farther the blade is from the radiator, the less air gets pulled through. Too far away and it just circulates air in the engine compartment.

[juanatejeda]

OK, that makes sense. Does anyone know what angle the blades are supposed to be? I seems that mine do not have much angle to them, maybe they just don't pull enough air through the radiator????? Does anyone have a picture of what the fan should look like?

[MikeC5]

Took the car out for a quick spin around the block (which does include some moderate hills) and it rapidly had the motometer up to the top of the 'efficient' zone. I noticed water steam escaping from driver's side (through louvers). When shut off, water/steam issued from the overflow tube for a minute or two, then just steam for a few more... It was only 72 or so degrees out. I'm pretty sure this isn't normal.. I had filled it up over the internal baffle when getting it ready. Could the block be getting air bound? Is it necessary to try and burp the system? I wouldn't think so. After it cooled a bit I pulled off the lower rad hose and little/nothing poured out of the block (boiled away?). I checked the water pump with a mechanic's bore scope and the impeller is there and turns with the pulley. Is there any way to test the water pump? As mentioned earlier in this thread, it is a honeycomb rad and certainly seems to flow good but I haven't been able to find any kind of spec. Fan is about 1" from the radiator.. I still need to check static timing... The hoses are new and showed no signs of collapsing. Any ideas?

[JayG]

Mike - I have a similar problem with my 25 and I suspect timing is the issue. I just ran across this article on vacuum timing the DB 4cyl. Haven't tried it yet but plan to. Jay

http://www.dodgebrosclub-australasia.asn.au/docs/vacuum_timing_db4.pdf

[MikeC5]

It's sure worth a try Jay. Thanks. Re-reading my recent post, it wasn't the lower rad hose I disconnected but the upper water pump hose (unbolted the fitting from the block). There was water up to the point where this hose connected to the pump. I suspect the water above that point had sprayed/boiled out. I suppose it wouldn't be a bad idea to pull all of the hoses and check for blockage. I don't know how a varmint could have gotten in there since all hoses were connected and radiator cap was on during the winter.... There sure isn't any thermostat to blame.

[MikeC5]

I just came across a thread that says painting the radiator with common enamel (spray can) paint can drastically reduce heat transfer (yes, I did it...). Anyone else have experience with this? I can't imagine how I would go about removing the paint (unless it dissolves readily with ??).

[keiser31]

You definitely have to use thinner radiator paint.

[cahartley]

OK, that makes sense. Does anyone know what angle the blades are supposed to be? I seems that mine do not have much angle to them, maybe they just don't pull enough air through the radiator????? Does anyone have a picture of what the fan should look like?

I had a 1920 Model T Coupe that had the original honeycomb radiator.......which I think looks cool........ :cool: .........so wanted to keep it.

The engine would overheat now and then, nothing drastic, but I still didn't like it.

I saw the fan blades had about as much pitch as a pie plate....... ........so I took a 16" Crescent wrench and something to lay on the block for a reference and twisted the blades some so they would actually MOVE some air.

The end.......

[Pete K.]

Mike, that paint you did on the rad. core will not make that Dodge overheat on any normal driving day. I say that is an urban myth the radiator shops started! After owning more that 22 old cars over a period of 44 years, I never had a problem with the coatings on some of the old jalopies I drove. Some overheated sure, but it was a clogged up or crud infested system. Go to a radiator shop and you will see many different looking paints they put on the cores. I've seen thick, tar-like goo one shop used, another one looked like they used high gloss black enamel paint, ALL over, not just the front. These were busy shops, in business for decades. I don't recall reading or seeing anyone returning to these shops from overheating after they got their car back. They did old car cores too. I cleaned my own '25 Dodge core and gave it a spray coat on the front of the core with semi-gloss black. It never overheats. It is not a honeycomb core but an original fin & tube core. Watch out putting too much coolant in. It should just cover the tops of the tubes inside, usually just below or at the level of the baffle plate. The overflow pipe will act as a siphon if it gets submerged for a short period, spewing a lot more coolant out. Some people have put a roofing nail in the overflow tube so the nail head covers the opening of the tube. I don't do that tho. There is no need to burp your system either. Once filled, it all goes in all the places it should. Only some heater cores had an air bleeder. I once had a '30 Buick six with a honeycomb core. It would overheat at the drop of a hat. One day it blew like Old Faithful. It never overheated again for the 19 years I drove it. Never could figure that one out. As far as electric fans go, there is much talk about them over on the Ford Model A group. Maybe Juan can find something there.

[Pete K.]

For a time tested way to really clean your cooling system, fill it up with white vinegar and run it for a few days. Drain it, flush it, you'll be surprised how clean it will be.

[MikeC5]

Hi Pete, I'm glad to hear your experience with paint on radiators. The paint story does have an urban myth ring to it... Do you just pour straight vinegar in there? I have been filling to over the baffle plate so that apparently wasn't helping.

[Pete K.]

Pour in straight white vinegar. I buy it by the gallon jug just about any place. Some guys run it for a couple weeks, I don't. I worry about the head gasket and others. Several days should do it, but you have to run it. Purge it and run your garden hose thru for a while. I even put in a tablespoon of baking soda to help neutralize it after draining vinegar without any foaming while it does it's thing with the water. Purge that and fill with 50/50 mix of Sierra antifreeze which won't FOAM at driving speed in these non-pressurized cars. Question; What did you do to inspect/clean your honeycomb earlier?

Juan, there's a picture of the fan in your owner's "Book Of Information". That should answer your question about what it's supposed to look like. There should be more like 1/2" - 3/4" between your fan blades and core. 1" sounds a bit far away. This distance does make a big difference. Do you have the engine "splash pans" in place? Is the fan belt slipping?

[MikeC5]

Hi Pete. I just ran it for a while with the straight vinegar in there. Just running it stationary at a fast idle and it heats up pretty quick. Even before the motometer reached the high mark it was spewing vinegar/vaporized vinegar. I noticed a very large temperature gradient from top of rad to bottom. By large I mean you couldn't hold your hand on the upper portion of the core for even a second while the bottom was hardly above ambient. I realize the idea is to cool off the liquid as it makes its way down but I suspect it has some significant clogging. I'll have to look at the fan and see if there's any way to move it closer. The radiator is back about as for as the mount bolts allow. Maybe I've got the wrong fan? I do have the splash pans installed. I'm checking to see what a new core would run (gulp)...

[MikeC5]

Also, I checked and adjusted the points and static timing. It appeared to be a little bit off. I also put a vacuum gauge on the vacuum tank T (for wiper) and found that with engine warmed up and the advance lever down (retard) the gauge was reading about 14-15 in. When lever is moved up to advance timing, vacuum goes up to 17-18. According to the "Vacuum timing on DB-4 engine" article I should be reading 18 at full retard... Perhaps timing still needs adjustment.

[MikeC5]

I did adjust the timing so I get a steady 18 in at idle (full retard). It does seems to run better but the rad, I think, is still a problem.

[cahartley]

Give the vinegar a chance. Drive it for a week.

If that doesn't do the trick you might try a $5-6 bottle of radiator flush.

There are all kinds but I used Prestone with the magic ingredient: organic compounds......which means sodium hydroxide AKA lye.

Liquid sodium hydroxide is used for boiling out new boiler installations too.

A weak solution is used and the boilers are brought up to not quite boiling and held for several hours.

I had to do just that with a 60 hp Case steam engine I once had as it was nearly impossible to fire....... :mad:

After holding the temperature at about 190º degrees for an afternoon you can't believe the crap that came out of that boiler....... :eek:

It was the end of hard firing too.......

[MikeC5]

I'm thinking you're right and the next step is the sodium hydroxide. Worth a try when alternative is a new core. I'm going to remove it from the (newly chromed) shell first and try to get some baseline measurements on flow rate. On one of the Ford Model A forums the number mentioned was 1 & 1/2 gallons (full rad) in 4 seconds or 0.375 gals/sec, or 22 gpm. I don't see why the DB should be much different. They look similar size.

[MikeC5]

Gents, I'm looking into getting my radiator re-cored and would like to get some measurements on an original round tube & fin unit and perhaps a close up photo or two of the header tank to core joints. I need core height, width (near bottom, I know it tapers a bit up near the top curves) and thickness (maybe a tube count front to back?). As I think I mentioned somewhere in this post, mine was re-cored at some point with a diamond cell type and I just want to make sure the header tanks can be re-used.

[Pete K.]

OK,... The '25 dodge Brothers radiator is made up of tubes and fins (on most I believe). The core is 20-3/4" HIGH from where the tubes are soldered onto the tanks. There are NOTCHES in the core at both upper corners, allowing the curvature of the SHELL to fit the core. These notches are 1-1/2" down from top, and 1" in at the sides, leaving 17-1/2" core width at the very top.

The core is 2-1/2" thick. It is made up of 100, quarter inch tubes. It is a FIVE ROW core, staggered tubes, starting with three tubes on outside row, then two, then three again, and so on as you look down from the top of the core. There are SEVEN flat copper fins per inch.

I don't think the honeycomb tanks will work with tube & fins, but I may be surprised. I don't think your overheating troubles have anything to do with your timing and spark advance, as you stated it is quite "right on" anyway. It takes quite a ways to motor in the heat to really see an overheating problem from that. I say you've got a clog somewhere in system. Before you go to the trouble of a recore, could you try Liquid Plumber or something strong in the core to dissolve any hair from nests?

[MikeC5]

Thanks for the info Pete. I did try some heavy duty potassium hydroxide and while it did seem to help as far as clogging it also sprung some leaks at the bottom header tank joint. Without having an original core to dissect I can't be sure these tanks will work. I think it will depend on whatever type of core I go with and what the top/bottom tube header plates (not sure what they're called) look like. The HC core I disassembled had simple folded over flanges (see pic).

[Spinneyhill]

"Grimy" said

"Straight [plain] water has a better heat transfer capability than an antifreeze mix--meaning that it transfers more engine heat to the plain-water coolant, but that's not the whole story. Antifreeze will boost the boiling point."

That was a surprise to me so I asked the internet about it. I found this:

http://homepage.usask.ca/~llr130/physics/HeatCapcityOfAntiFreeze.html

So what it means is that at 71 degrees C (about 160 F) and at 93 C (about 199 F), it takes about 9.5% less energy to raise the temperature of a 50% ethylene glycol (EG.) + water solution as it does using a 25% mix. This means higher-EG.-content coolant temperature rises faster, and thus more, as it passes the combustion chamber, so you could say that with the same coolant flow, the coolant (engine) will run hotter. Increasing the EG. content makes it worse with a rapid rise as you get towards 100% EG. coolant. If you say maximum cooling efficiency is achieved with minimum coolant, then plain water is better. Engines also run more efficiently at higher temperatures. I need to think a bit more about what happens when we try to remove that heat energy from the coolant.

Remember, however, that if plain water were to be used as an engine coolant, it would promote galvanic corrosion.

Anti-freeze lowers the freezing point of course. But what about boiling point? 100% EG. has a boiling point of 197 deg. C, so mixtures with water raise the boiling point in proportion.

EG. is stable and does not evaporate. So why is it recommended to change it every year or two. From Wikipedia,

"When ethylene glycol is used in a system, it may become oxidized to five organic acids (formic, oxalic, glycolic, glyoxalic and acetic acid). Inhibited ethylene glycol antifreeze mixes are available, with additives that buffer the pH and reserve alkalinity of the solution to prevent oxidation of ethylene glycol and formation of these acids. Nitrites, silicates, theodin, borates and azoles may also be used to prevent corrosive attack on metal."

Anyway, if your car overheats in slow parades on hot days, the cooling system is not efficient enough. You may gain from using plain water, but you will still struggle to remove the heat from it. You need increased capacity of the system:

clean radiator core;

maybe more rows of tubes (has it been recored and did they put enough rows in the new core?);

functioning thermostat (removing the thermostat may reduce head losses after the pump and increase flow, but not much);

functioning water pump;

no blockages in hoses;

no build-up of "crud" in the block;

as-designed set-up of the engine compartment, including the side panels where fitted;

fan with correct pitch and number of blades;

correct size pulleys so the fan turns at the right speed;

good belt and belt tension so fan turns at the right speed;

radiator filled to 3" below top (it'll blow out the rest).

Is that enough? Good luck.

[MikeC5]

A thorough list of things to go over for sure. There is no doubt I need a new core though. I am going over the water pump and will be checking the block too. I've been using water since I only drive it short distances while restoring things (plus it overheats quickly). No thermostat in this vintage. I never leave the water in there for more than a few hours...

[Spinneyhill]

I think I have read somewhere that one should keep the cooling system full to promote longevity of the metal components. I'll ask the internet about it; maybe you can too.