This is not making any sense. My '50 Ford with the flathead V8 is acting rather strange. A couple weeks ago I changed the coolant after removing the heater and bypass hoses. Now it seems to blow out coolant out the overflow whenever it chooses. By this I mean today I drove all over town stopping and going running errands, and when I got finished and parked her in the garage the coolant level was fine. Well after lunch we decided to take a drive, a 60 mile round trip out to the country running about 55 - 60 mph. When we returned about a pint of coolant had gone into the overflow. The car runs perfect, no over heating, no smoke, has the correct radiator cap that's about a year old. I made sure that there is no air pockets after the fluid change, and I can see the coolant flowing pertectly as it is running. I have the coolant level just above the coils in the radiator. I did a compression test yesterday, and except for #5 at 70 pounds the rest around 90# the same as it tested a couple years ago. Prestone antifreeze with 50/50 mix is what I always use for coolant - so what are your thoughts - just live with it or ???
Are you topping up the radiator? The fill level should not be to the top of the tank, but almost 2 inches below the radiator cap. The room is for expansion when it gets hot. If it is too full it will blow out the excess as you have noted. Just keep driving it and see if once it reaches a certain level it stays there. Of coarse watch the temp gauge. If it heats up you have a problem.
The Number one rule of fixing stuff "when a new problem surfaces , go back to the last thing you fixed, touched or changed" Should be a tattoo really.. A couple weeks ago I changed the coolant after removing the heater and bypass hoses.
I think what B J R is saying could be the answer. I would leave it alone and see if the overflow get any fuller. It will level out and stop pushing coolant into the overflow. And I think the reason you seen it after a long drive is that you checked it after you got home. Let it cool down and see if it pulls some back in to the radiator. Good luck
i have to agree, so the heater is no removed from the system all together? could be enough to raise the temp in the rad now causing it to blow over
By removing the heater and bypass hose, you lost at least a quart of coolant the system can use to keep cooler. When you reduce the system capacity, you are using the remaining coolant more then the system was designed for, its going to run a bit hotter. If the system is running at near capacity and you reduce the amount of coolant available, you lowered the capacity and its bound to overheat. Gene
I have the coolant level just above the coils in the radiator. The amount of coolant will not change because the heater box was bypassed and blocked off. I have already gone thru the series of running it and letting it flow over into the overflow to find "the level" she likes, but it continues to keep over flowing. And again it doesn't over heat and both temp gauges never go above 190.
I am not familiar with the water flow pattern of a 50's Ford, but.... It is possible that by removing the heater and bypass that now too much flow is trying to go through the radiator core at higher RPM. It would then pressurize the radiator enough to over come the pressure cap and loose coolant. Is it possible to replace the bypass and see if the added flow stops the problem. I had this happen to a 32 Hupmobile I had with a new radiator. I had to put a restrictor in the top hose to reduce the coolant flow at high RPM.
I had a similar problem with a modified cooling system. Also no heater fitted. I had a filler / expansion outlet at the highest point in the cooling sytem which was at the water outlet from the head on a four banger flat head engine. However once the engine was running the flow of coolant pushed the bubble of air in the system around to the top of the radiator. So at the expansion outlet there was no air to breathe in and out during the heating / cooling cycle. So it pumped a bit of water every time with the end result of a large volume of air in the radiator and overheating problems. I've now fitted a header tank on the bulkhead which drains back to the radiator and the problem is fixed.
My '52 with the original flathead had the same problem, could run around town all day and not lose any coolant, but if you wound it up on the highway for a while it would spit a bit. I finally ended up replacing what I thought was a good radiator cap, hasnt done it since. As for the heater issue, the way mine is set up stock it blocks the flow of coolant to the heater to regulate heat, so removing it from the circuit should be no different than not wanting heat in the cabin. Not sure if '50 is set up the same way.
What pound radiator cap are you running on that original radiator? Caps can and do "wear-out". If you've lost some spring pressure, that could/would do what you're describing. You can't go too high with an old radiator, but 6 or 7 pounds is where you most likely need to be.
Coolant expansion resulting in the lose of coolant can be an ongoing problem, especially when driving at highway speeds. I would suggest that you check the cap to make sure it is holding the designed pressure, about 7lb's for the pre '60 vehicles.. Add a coolant recovery tank into the over flow line.. I make my coolant recovery tanks out of 2" black ABS plastic pipe, about 18 or so inches long. Glue a cap to one end, drill a hole into the cap for a 1/4" fitting, attach the overflow tube to same. Drill a hole large enough for a 1/4" elbow fitting about 2" below the top end, attach a piece of hose for an overflow. Put a 2" plastic cap on the tube and mount same with plumbers tape or radiator clamps. I like to use clear tubing from the radiator to the overflow tank, this give me a 'sight tube' to check the coolant level.. The whole assembly costs under ten bucks, and the black ABS pipe tends to become invisible, where-as one of the billet puke tanks cost big bucks and sticks out like a sore thumb...
Specs for a '49-51 is 4# with a 1" deep opening - as you know most necks are 3/4" deep. I just bought a new one today - made in Mexico - wish me luck.
When you turn your heat off, it's the same as eliminating the system. Buy a new radiator cap. Seriously. I said it first, and others said the same thing. They are like $10 at the most. Go get one and try it.
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