Pressure check a Hemi or whatever block

Got an idea of how I should do this but checking with you guys on your ways.

You can bolt it together with the heads and put a pressure inlet port and gauge on block plates on the water pump inlet and outlets(both sides) and apply air pressure and get a spray bottle of soapy water and go searching all over the heads and block
I've used a torque plate to pressure check aluminum heads that had been welded on, that works also

So you use air instead of water? At what pressure? Would an engine "see" 20# or more pressure running?

Air pressure works. But you want to pressure test it assembled. If you have one, a leakdown tester will show pressure loss. A squirt bottle with water only works on external surfaces but you can have internal leaks. 20 lbs is plenty - rad caps are rated at what ... 15 psi? So you don't need much more than that.

Use my pressure check kit. http://arengineering.com/products/pressure-checking-kit-bb-and-hemi/

Engine in car or bare block on the stand?

That's what I'm talking about I made my own out of 3/8 plate steel

Your choice, it will, or should test the same either way Probably easier on the stand so you can look at the back, sides and front of the motor on the stand

I don't use water in the block or heads Air pressure and soapy water, on the aluminum heads that had cracks and had been welded on already I used 30+ Lbs. of air pressure to make sure they where sealed up after having those welds welded up over again

Not to get off subject but, how long should the pressure hold in the system without any loss?

Digger73 (Mike(

I had rust in the cylinder and I did what I had to to check it. Block check

Unless the leak/crack/hole is really bad, a cast iron block or cylinder head will most likely not show a leak unless you can heat it up. Pressure checking one cold and it not showing any leakage doesn't prove anything.

There have been posts with heat coils going into the block moving hot water.I pre heated the block,put in hot water then seald and continued heating it

As to pressure test with no loss. I recently left my Cummins over 24 hours with no pressure lost. Yet when it was warm it would weep coolant that I could smell but not ever see. Turned out I left the head bolt at the very rear under the cowl finger tight. I'd use 30 psi with soap water.
Doug

Uh, forever. Anything less would be a leak, right ?!?!?

I've used a propane torch to heat up cast iron to see a crack better, it does make them rascals appear a lot easeir

On a stand, bare block. I was going to make a head plate of 1/4 aluminum but the kit said without a head it needed a torque plate.? I figured 40 psi would show any cracks, no mater how hot it is. But that's why I'm asking.

The pressure test rack I used at the machine shop would go to 35 psi (IIRC) and it wouldn't make a crack bubble on a cold cast iron head...one we knew was leaking on the car.

Shouldn't leak at all if sealed up good. May have a little fluctuation with temperature change.