MarkDonzi

I want to test my headers for leakage. What kind of pressure should I use? I have 600SCI motors.

Also, has anybody tested them while still on the motors, I have a staggered setup and plenty of room in the motor box and it looks like with a little plumbing it could be done.

Thanks, Mark

Young Performance

It is so much better to test them on the bench because if they leak, you can not only see it, but you won't put water in the exhaust ports. Just use your garden hose with city water pressure(or well pressure if you have a well). It is more pressure than you make in the boat, but you do not have the heat. I have seen some exhaust not leak on the bench, but leak in the boat when they got hot and the crack expanded.
Eddie

Tarheel

I just took my headers off to do the same thing. Mine are 4 years old and I figure they need to be tested. Took an afternoon to pull them - not too bad.

I've got to get the service bulletin recall work done for my 525 starter wiring, so I'll leave them off so they can get to the starters a little easier. I notice two of my hoses between the end of the exhaust tailpipe and the exhaust tip were blisterred. I'll replace all of them while I have it apart.

I had some GIL manifolds on an older 500HP boat tested, and I remember the Merc guys pressing them up to about 15 or 20 psi with a hand pump rig.

MarkDonzi

Thanks for the info guys