I have had trouble keeping water in my car since the start. Used to push out the overflow until I put on a lower hose that didnt collapse and a overflow bottle. Tried different caps too. Now, there is no more water leaking under the hood. After about a 75 mile drive , I was 1/2 gallon low. Radiator was topped off before I left. I used a "block tester", and could not get the liquid to turn blue. Also, no cylinders are filled with water at start up. All the plugs are new and clean.....so I cant tell anything there....and compression is even. I am not sure where the water is going....the only thing I can guess is through the intake? Its not in the oil......
Do you have access to a pressure tester? Should be able to find the issue with one. One more question, how does the exhaust smell?
Does a pressure tester merely pressurize the system with air....like say, a radiator hose with a valve stem? I will google it. The exhaust smells like a car with too much valve overlap, but no antifreeze....at least idling in the driveway, or shall I say, backyard.
The pressure tester is a hand pump with an adapter to go where the radiator cap goes. You might be able to rent one from Autozone.
It looks like autozone does loan that tool. If I pumped up the system as is, and positioned the engine so that #1 and #5 intake valves were both closed, If I had an intake leak, would I hear some hissing or gurgling through the carb? Or would that be better tested with coolant drained off? that would assume the leak would happen on a cold engine too I suppose. Would it be better to bring it up to operating temp first?
Pressure test should not make a difference if valves are open or not. Basically you're verifying system will hold pressure. It's fairly safe to say coolant isn't getting into cylinder(s). The several 1000 psi combustion would be pressurizing cooling system, coolant recovery bottle would soon overflow. If recovery level isn't abnormally high, could have a leaking intake gasket. Design of gasket(channel around coolant ports) is supposed to allow coolant to leak externally before it enters engine. Doesn't always work that way though. Small leaks internally aren't always noticeable, but yours isn't exactly small. Last leaking head gasket I had, compression was pressurizing cooling system. While running, coolant appeared to be full of Alka Seltzer. Last blown gasket was between cylinders, lost no coolant at all.
About all you can do is pump it up, look and listen. I just used mine to figure out where coolant was going on my dads old truck. I wasn't leaving puddles or signs of leakage either, turned out to be a bunch of loose clamps and a small leak in the radiator. His wasn't losing as much as yours but we were able to find most of the issues that way.
If you are using the stock radiator they do not like being filled all the way up, leave the level down about an inch below the he top of tank and check and see if that makes a difference. If it was leaking into combustion chamber I would think that you would see it in the exhaust as water vapor coming out. The last time I had this problem it was the heater core, that reminds me I have not fixed that yet arrrgh
I am going to get that pump and pressurize the system to see what I see. I put a new heater core in, but I will check under the rug anyway, cuz because. I noticed that....I finally let it be an inch "low". But the water level will drop down below the bottom of the top tank. I need to rule out all the simple stuff I guess. No foam ever showed up. I did R&R the intake gaskets before it was running because I could see orange silicone that oozed into the intake ports in big globs when the carb was off (single plane, torker 289). So, I dont know if I got it buttoned up right or not....seemed like I had to do a lot of laps around the bolt pattern before it sat down. I have no idea who put this engine together, or when, or much of anything about its past. I do know the cam has too much overlap, and I think getting rid of that and putting a dual plane on it would be nice. So would a roller block, and better heads.......LOL. Water leak first!!!!!
Well it will be interesting to see what the results of pressure testing the system shows, without any visual leaks it sure sounds like a bad heater core I have heard of several new ones that were not good, you could just bypass it and check but just seeing if your carpet is wet is easy enough to do but with the rain we have had that could just as easily be a leaky cowl or windshield rubber. Another thought is a bad water pump leaking through the weep hole or possibly a freeze plug leaking. I assume that you have just been checking the loss of water at home with no road test
Well, after R&R of heater core, I had to add more water. Nothing strange there. Short time later, another half quart. Still not strange. But after about 50 miles on the road, another half gallon? Makes me wonder about all the times I have added a little water to get the level up. I have chased leaks here and there, but have none I can see now.....so the tester may point one out. I also went through a bad radiator cap, lower hose that used to collapse.......used to get antifreeze all over under the hood if I got on it .....but not any more. It is all clean and dry, even after a good flogging. If it doesnt rain tomorrow, I might mess with it. It has been sitting for about ten weeks, mostly out of disgust, but March is only another 10 weeks out, so my interest is sparking a little.
if the cap is good, fill to the 1" below full. then let it come up to temp then shut it off, check for leaks. the engine should heat soak and the pressure will go up. just like a pressure checker. Frank
I have a friend that his 302 in a '65 Shelby lost coolant with no explanation. Was OK after intake gasket replacement and a short time later, started the process again. To make a long story short, he finally found the intake bolts were maybe .050 too long. Another set of bolts and problem was fixed.
