I had a mysterious coolant leak about 2 years ago. Mech. put some radiator leak stuff in with a 16 psi cap instead of an 18 psi. Leak gone. Well, like an idiot I put a nice, shiney, new 18 psi cap on (got it for free.) Well, leak is back. Instead of a bandaid, I'd like to fix it. I've checked the water pump seals and seep hole, not leaking. I checked my hoses, no cracks or holes. Normal colored oil. Exhaust doesn't reek. No smoke or water coming out of the exhaust either. No wet spots in the pass side carpet or sweet smell. Where the hell is it going?? Every third to fourth day, the light comes on and I have to fill the rad. back up again. Any ideas or help, would be appericated, thanks.

 

Intake gaskets. The leak is so slow you never notice it at the exhaust.

 

except for the fact that there is coolant no where near the intake gaskets.

 

Could have a bad radiator, their not to bad to get fixed, just replace it, might be a good idea anyways since some of these cars are going on 10-12 years.

 

If it is going down that slow and you are positive there are no external leaks, you might be burning it in the cylinders without knowing it. You might want to do some pressure testing of the cooling system and/or cylinder leakdown testing.

 

I had that same thing happen to me. Turned out it was a bad head gasket. It wasn't completely blown, just a small leak between #3 and #5 cylinders. As Shoebox mentioned, a pressure check should detect it.

Good luck.

Mike

 

Thank you for the replies. I remember the mech put a machine on the the rad to apply pressure. Said not worry then applied the rad leak fix. If it is leaking into the cylinders, what does/would that do to my engine. Car still feels fine. I was wanting a Be-Cool rad anyway. I'll take it back to him on Monday for a pressure check.

 

If it is leaking into the cylinders during operation it won't really harm your engine but I'd really keep an eye on your oil to see if gets contaminated. It'll just continue to consume anti-freeze and eventually the head gasket will let go completely. It will either start stumbling really bad like mine, or she'll really go and you'll see white smoke out the exhaust. When mine started to go I thought it was the opti.

Mike

 

How hard is it for a do it your-selfer to change head gaskets?

 

me too.

fix asap before the gasket really lets go and you are stranded and even worse have contaminated oil and washed bearings.

press test identified a slow leak and when starting up after the test I had forced coolant into a cylinder upon start up I new for sure what it was from all of the smoke.