MTFCA Forum

I have put this up before but thought it could use a reboot. All T blocks that come here for work are first given a pressure test. I made tooling and bolt down a head with a reusable rubber gasket. Then the whole thing is filled with water and pressurized to 20 psi with a radiator pressure tester. More than a few times I have found leaks that would only have come up after I built an engine and a customer put water in it. Not a phone call I want to get.

Thats a nice set up you got there!
How long do you usually let it set to see if pressure drops?
what are common leak areas you find?
Bryant

I run a heat gun across the popular crack areas as some cracks open up when warm. The passenger side especially under the overhang and also around the freeze plug holes and through the gap between 2 and 3.

Andy

That's a very good idea. Adding a small amount of dish detergent, like Dawn or Ajax, to the water in the block will help find leaks. Ford tested new blocks to 50-60 PSI. I think limiting pressure to 20 PSI is a good idea for blocks today. I'd make an effort to get the block and head completely full of water, with no air bubbles.

I like the test plate sold by a vendor. You can see inside the valve seat area. It works on heads too.
I modified my KRW engine stand so I can turn engine over and see all sides. Dan o

Here is my block pressure testing setup. I fill the block with water using the head inlet to as high as it will let me. This assures the block water jacket is completely flooded. Next I attach the air supply to the head inlet and pressure it up. Then look for water seepage. Needless to say before filling the block with water I cover the block’s water inlet, and if needed, the so called freeze plug openings. On this particular block I initially forgot about those freeze plug openings! I had to sacrifice a set of brass plugs, not having any steel ones sitting around and I didn’t want to take the time to try and manufacture three plugs from nickels. By the way the pictured block is a 1918 I bought from Erik Barrett at the Tulare swap meet earlier this year. It had a water jacket crack in the usual place, but was otherwise a nice block. It gave me a good opportunity to improve my Lock-n-Stitch skills. The water jacket was not rusted thin at all, making it an easy fix using the overlapping pins. I sent Erik photos of my stitching work so he would know the block was fixed and tested.

Rich C.

I don't think detergent is a good idea! It might be good for finding leaks, however very hard to clean out! I once had a Model A in which I used some detergent in the cooling system to clean it out. Even after flushing it out many times, for weeks it was like Lawrence Welk's bubble machine!
Norm

Been a while since I posted this - always had a coolant leak - once I removed all the solder & JB Weld this is what I found !!! Not sure the stitch method would work on this crack !

I got some test plugs for the Welch plug holes. I use these to plug up valve guides to check for cracks in them.

Steve, is Longbranch near navigatable water? That block would be good for a boat anchor, but I think you should look for a better one to use in your T.
Norm

Steve: That block could be fixed with LocknStitch method, but is it worth it. I have seen it do amazing things. But maybe cheaper to find a new block unless it is rare one.

Wasn't my block - came in the shop years ago to see where it was weeping and yes Norm, we're walking distance from the water !

I had one like that come in years ago. Had been rebuilt and always leaked. Not bad just stayed wet, same place as that one. After I got all the JB crap off, found someone tried to weld it up. It had cracks going everywhere. Got new block.

Too busted up for me to mess with so a buddy up in Canada took it home to practice welding on !