So I performed this test to see if I have a coolant seal issue. I had hot start issues but my compression tested great...

I put an hks twin power and that seemed to get rid of the hot start issue. At least 95% of it. There are occasional times I have to crank it a few times and feather the throttle to start but not too much or too bad as before the hks tein power.

it also was losing coolant every so often I drove. I’d have to refill it. I can hear it bubbling inside after I shut the car off. I don’t think I bled the coolant system properly after putting the water housing and pump back in. Don’t know if that would have anything to do with leaking coolant..

but here are the results from the coolant test. Picked this up at local auto store. It says if exhaust gas is present then it will turn more yellowish green. But if not the color will remain blue. What do you guys think? I performed the test on my Supra as well. And I think it was a tad more blue than the 7..? But I think 7 didn’t turn quite green or yellow...?

make as you can see the fd fluid level went up vs the Supra remained the same...??


This is from the fd

Also fd

Supra

Supra

 

Pressure test the coolant system to see where its going. If it leaks down but there are no external leaks it is going into the motor. Usually this will be accompanied by hard starting the next time you try to fire it up as the motor will need to clear out the coolant.

 

ok gotcha obviously the seal would be bad if there is no external leaks right but the coolant goes down?

 

Most likely but a pinhole in the system would also prevent it from recovering the coolant out of the overflow as the car cools. Eventually the overflow will leak when it overfills.

 

Bad water seals manifest as hard to start cold, especially if the car sits a few days. Smoke and rough running. Typically doesn't contribute to hot start problems.

If you are losing coolant it's probably a very small pinhole leak as Ihor stated, either in a hose in the pressure side or the hose to the overflow tank. Pressurize the system and see if it holds pressure, if not find the leak.

Dale

 

I am having the exact same issue, except my car starts fine. Constant bubbling and the overflow tank overflowing without pulling coolant back into the car when it cools. I have replaced the overflow tank, hose with it, AST, radiator, and caps. Curious to find what solution you come up with.

 

Steve, you need to have me look at your car one of these days .

It could be a really minor leak that's not enough for coolant to get into the engine but enough that exhaust or compression pressure gets into the cooling system. Or you have some major air pockets or other leaks.

If you start it cold with a funnel on the fill neck does it bubble up?

Dale