The Ford Barn

revkev6 · 10-10-2017, 02:32 PM

here's the pics from my afternoon yesterday. spent 2 months asking around for the "proper tool" or a recommendation for a shop when I should have done this from the beginning. took me a couple hours to make it up and test both sides.

rotorwrench · 10-10-2017, 02:45 PM

The only problem with using the heads for pressure testing is that you can't tell where the cracks are as well as you can with plates if properly made. If a person doesn't want to pin the leaky cracks then it won't matter much. Some cracks are in places that can't be pinned anyway like the ones down inside the center exhaust port area. If it's in the valve pocket and doesn't go too far down into the bowl, it can be pinned. Most exhaust valve seat area cracks can be seen with the naked eye so that's the first place I check.

revkev6 · 10-10-2017, 02:50 PM

Quote:

Originally Posted by rotorwrench

The only problem with using the heads for pressure testing is that you can't tell where the cracks are as well as you can with plates if properly made. If a person doesn't want to pin the leaky cracks then it won't matter much. Some cracks are in places that can't be pinned anyway like the ones down inside the center exhaust port area. If it's in the valve pocket and doesn't go too far down into the bowl, it can be pinned. Most exhaust valve seat area cracks can be seen with the naked eye so that's the first place I check.

right, but this block had frozen and cracked the pan rails. 30" of weld in them!! beautiful welds but you just can't fix the ports. given that I smelled coolant in the exhaust and had some odd bubbles in my radiator I suspected I had cracks in the exhaust ports. I tried for the plates, but this was going to show me what I suspected.

revkev6 · 10-10-2017, 07:09 PM

Ok.. just picked up a stock rebuilt 8ba never fired! Got a good deal. Swap out my stuff and go!

RalphM · 10-11-2017, 12:30 AM

Sorry about the test results, but sounds like you have another Candidate ready to go. There are plenty of flatheads still out there.
I was going to put a 40 motor in my 35, but procrastination led to a low mileage 59AB that fell in my lap!

10-10-2017, 02:45 PM	#22
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,436	Re: exhaust crossover and pressure testing The only problem with using the heads for pressure testing is that you can't tell where the cracks are as well as you can with plates if properly made. If a person doesn't want to pin the leaky cracks then it won't matter much. Some cracks are in places that can't be pinned anyway like the ones down inside the center exhaust port area. If it's in the valve pocket and doesn't go too far down into the bowl, it can be pinned. Most exhaust valve seat area cracks can be seen with the naked eye so that's the first place I check.

10-10-2017, 07:09 PM	#24
revkev6 Senior Member Join Date: Nov 2012 Location: western Mass Posts: 365	Re: exhaust crossover and pressure testing Ok.. just picked up a stock rebuilt 8ba never fired! Got a good deal. Swap out my stuff and go!

10-11-2017, 12:30 AM	#25
RalphM Senior Member Join Date: Nov 2015 Location: North Pole, Alaska Posts: 2,651	Re: exhaust crossover and pressure testing Sorry about the test results, but sounds like you have another Candidate ready to go. There are plenty of flatheads still out there. I was going to put a 40 motor in my 35, but procrastination led to a low mileage 59AB that fell in my lap!