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Going to be installing the cylinder head that I got back from the machine shop soon. I'm thinking of leaving the intake and exhaust manifolds pulled back from the block so I can see if there is a leak when I pressure test the system after the head is torqued down. If the gasket does still leak would a pressure test necessarily show leakage or does the motor have to be up to operating temperature before it would leak at the gasket?
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TR2/3/3A Pressure testing the radiator to find a head gasket leak?
- Thread starter karls59tr
- Start date
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I have seen a crack in a block not open up until the engine was warmed up, so maybe or maybe not. The leak could be in the block. I would think the shop gave an ok on the cylinder head for cracks in the water jackets. Sounds like go for it and see at this point because the block is an unknown.
steve
steve
charleyf
Luke Skywalker
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Do you have a heater in your car? If so do not do a pressure test above the 4 #, which is not likely enough to show you anything. You will blow out your heater . Unless you isolate your heater first.
I agree with Steve. You are not likely to show any problem with this test.
Charley
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Karl I wouldn’t bother with your pressure test.
I fear a test like this could cause problems for you.
Eg the cabin heater as Charley says but the stop valve o. The head only stops the flow the other end is open to the system.
You head shop should have done a good job - it’s what they do- so do a careful assembly with a good and well fitting head gasket.
Torque it up in stages and the coolant slowly ( sometimes helps to have the car angled up at the front) to stop air locks and run it.
Retorque the head after a few heat cycles 200 mile plus should do.
And enjoy.
I fear a test like this could cause problems for you.
Eg the cabin heater as Charley says but the stop valve o. The head only stops the flow the other end is open to the system.
You head shop should have done a good job - it’s what they do- so do a careful assembly with a good and well fitting head gasket.
Torque it up in stages and the coolant slowly ( sometimes helps to have the car angled up at the front) to stop air locks and run it.
Retorque the head after a few heat cycles 200 mile plus should do.
And enjoy.
How high should the front be angled up in order to prevent an air lock?
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I just raise the front so both wheels off the ground whilst filling the rad enough to fill the engine block and cabin heater etc
Then lower it to make sure I only have a thin covering of coolant in the long neck.
Just enough to wet your finger when dipped in ( when cold !!)
I run the engine with rad cap off to see if it “burps” ie big bubbles being released.
Cap on and check dash gauge
If rad hot and temp cool there is an air lock.
Then lower it to make sure I only have a thin covering of coolant in the long neck.
Just enough to wet your finger when dipped in ( when cold !!)
I run the engine with rad cap off to see if it “burps” ie big bubbles being released.
Cap on and check dash gauge
If rad hot and temp cool there is an air lock.