The Ford Barn - View Single Post - Coolant flowing from radiator cap at speed

Simonpie · 04-24-2017, 09:51 PM

OK I'm going to highjack this thread a bit. I have the same problem on my speedster. Overflow at the cap at high revs/throttle. My first thought was a blown head gasket. This is a 100 mile motor, so anything is possible. I did a compression test and all across the board was an even 82 (B head skimmed). So my question. Is it possible it only leaks at higher pressures? I can do a leak down, but that's only 100 PSI or so. Should I assume the head's OK and start looking at all the other overflow ideas on this list? Remember, it spurts out the cap, not just dribbles out the overflow tube. Is there a better head gasket test?
Luckily, it is a speedster, so I catch the antifreeze with my face, thus saving the environment.

04-24-2017, 09:51 PM	#17
Simonpie Senior Member Join Date: Mar 2015 Location: Portland Or Posts: 137	Re: Coolant flowing from radiator cap at speed OK I'm going to highjack this thread a bit. I have the same problem on my speedster. Overflow at the cap at high revs/throttle. My first thought was a blown head gasket. This is a 100 mile motor, so anything is possible. I did a compression test and all across the board was an even 82 (B head skimmed). So my question. Is it possible it only leaks at higher pressures? I can do a leak down, but that's only 100 PSI or so. Should I assume the head's OK and start looking at all the other overflow ideas on this list? Remember, it spurts out the cap, not just dribbles out the overflow tube. Is there a better head gasket test? Luckily, it is a speedster, so I catch the antifreeze with my face, thus saving the environment.