VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 keeping a cool 28 sedan

Hello: I'm a newbie both to this forum and old chevrolets. For background, I had a 1918 American LaFrance firetruck in my garage for 23 years and never got beyond plating and engine work. A friend and fellow collector always wanted to trade me out of the rig and finally got what I wanted, a 28 AB 2 door sedan which served as the Fire Chief's car in a mountain town of Victor, Co. The car has been externally restored ... new paint, upholstery, tires, battery and details. Will submit photo when I figure out how to do it. It runs great and I am finishing off the engine compartment. The primary concern now is overheating. The two times I've had it out it has dropped some antifreeze ... not great amounts but trips were very short. If the car is let idle for long periods of time and not under load, its dry as a bone. I am flushing the radiator as first step. I've learned there are some tricks to cooling I was unaware of such as restrictors in the radiator hose. I need some lessons in cooling the beast. For instance, will a four bladed truck fan help over the stock two blade? What thermostat is best? How do I tell if timing is right? (So far it sounds great and runs like a toop ... except for times when I want to stop ... but that's another subject to come.)

Any advise will be greatly appreciated.

If you can let the car idle for long periods without problems the cooling system may be ok. I would first check the packing nut on the water pump. It should be snug but not tight. If any water is seeping out then air will be sucked in. The air is sucked in to the cooling system past the packing, bushing and shaft. It is not necessary to have a water leak to still suck in air. The higher the water pump speed the more air is sucked in. The air takes the place of coolant and when the rpms drop the internal pressure (in the engine) is reduced and the air bubbles get bigger and force coolant out the overflow. It is a common problem that is rarely correctly diagnosed. Oh yes at idle the pump speed does not often create enough vacuum on the shaft area to draw much air but higher pump speeds create more vacuum and therefore more air. Restriction in the block outlet hose will help reduce coolant loss as it helps to pressurize the block at running speeds. Now it does not pressurize the entire cooling system only between the water pump and the restriction or radiator.

You can also add an overflow tank like on modern cars and trucks. Just put it on the over flow pipe and make sure the radiator cap seals the neck. It will work just like a pressurized modern system. Contain coolant pushed out of the radiator and pulling it back in. It will also help get the air out of the cooling system.

I could write a book on cooling systems but this will have to do for now. Otherwise BB will take my privileges away.

SHOOT! Chipper, Old BB may even give your own private forum, where you can impress us with your vast amount of assorted and maybe some sorid knowledge, without having to let us reply to the sorid stuff!

Thanks for the tips. A couple of added questions, then. Where do I get a restrictor or is it hand-made? Is there any advantage to putting on a 4 blade fan and if so, where will I find one?

I appreciate your interest and look forward to additional help as I go along.

PS: I have a web site; traceenterprises.net, and will post photos there in near future. Dale007

My '28 pushes out an amount of coolant until it reaches a working level, just due to normal expansion. The level then stays consistant, about 3/4" below the plate in the filler neck. Are you sure yours is not just doing the same?
Tim.

If the car does not overheat at idle then the four blade fan will likely not do much for you. It may help at parade speed. At 10-15 mph the fan does not effect cooling at all. More air comes through the radiator from the movement of the vehicle than the fan can draw in. The restriction can be as simple as is a washer in the top radiator hose with 3/4" hole in it. Some say a smaller hole is better. All the restriction does is pressurize the cooling system between the water pump and the restriction.

I appreciate the added advice from y'all.

I'm pleased seeing so many Texans with these fine old cars. My wife's from Dallas and I told her of your local clubs and the many restored machines back there.

Thanks again, Dale

This overheating and losing water problem sounds the same as mine. (See my post-1919 Chev FB sedan Baby Grand) We tried a restriction in the top hose but it did not seem to help. I am not sure what is meant about the water pump and the air. It seems like we all have the same situation though.

My Gosh, I looked at your replies again and realized Tim Bailye is from Down Under. Didn't mean to put you in with the wild bunch from Texas. I will check to see if I'm loosing only a nominal amount of coolant at start-up. I may only be a nervous nelly here. However, I also run a 36 Ford 5 window coupe street rod with a 350 Chevy in it, and it still is giving me heating fits on the road too. In its case, I have no conventional fan as I had to shoehorn the motor into limited space and added an electric fan in front of the radiator. I had even considered this option for the 28, but obviously haven't done enough testing yet.

As for parade use, I believe this may be my best option until I can see how to make the beast stop once it gets up to 45a or so. With mechanical brakes, theres a certain amount of "fear factor" working, is'nt there?

Thanks to you all, Dale

Hey, Don't fret! I'll proudly stand along-side a Texan any-day. Apart from those funny hats and amazing accents, they seem a pretty decent bunch!
Tim.