Overheating block

[TuffRR]

Heres the situation:

4.4 Rover block machined, new pistons etc etc. Reco’d heads, new gaskets etc etc, full rebuild. It had a constant air lock from the beginning. Drove it about 50kms on the highway and it blows a head gasket. Temperature gauge was reading normal. Remove heads, discover that the RHS head has gone soft.
Pressure tested the block with heads off, had water jackets covered with plates. Pump the system up to about 15psi and water would stream out of the block where it had been drilled for the oil gallerys to the heads (4.4’s originally ran hollow pushrods to supply oil to the heads). The water was coming out on both banks. The sump was off at this point and NO water was escaping underneath.

The repairers currently have the block and have pressure tested it themselves. They cannot get it to leak at all. WTF? As far as I know, there is absolutely no way water should be running through the oil lines other than if a) cracked block, b) block drilled wrong when doing oil gallerys or c) porous block. What I don’t understand is why they can’t replicate my results with the pressure tester. He reckons he had the pressure up high enough to pop a hose off but not to escape from the oil gallery.

I’m heading to the repairers Saturday morning so the bloke can run me through what they have done. At this stage they can’t fault the block (because its not leaking). My concern is that they will try to wash their hands of it because they can’t find anything wrong.

Anyone suggest some more ideas or things I should look out for on Saturday?

TIA.

[-Scott-]

Is it possible the plates you used to seal the water jackets didn't seal them well enough? Water might have been flowing from water jacket to oil galleries between the plate and the block face. Either the block face isn't flat or the plate bowed with the pressure? Did you have head gaskets between the plates and the block? That might help seal better.

Did you have oil in the water when the head gasket went? (I know that it's a long shot, the answer is probably yes...)

On Saturday, take all the stuff you used into the repairers. If you can replicate it with your setup, but not with theirs, work out what the difference is!

Good luck,

Scott

[V8Patrol]

On Saturday, take all the stuff you used into the repairers. If you can replicate it with your setup, but not with theirs, work out what the difference is!

Good luck,

Scott

Simple advice that should work in your favour..... gotta be a good thing !

[TuffRR]

I picked the car up yesterday after the repairers handed it back saying they could find nothing wrong with the block. They had put it under pressure a couple of times and could not find any leaks. They had used metal plates over the end of each bank (the heads are off) to cover the water jacket at back of block and the oil line at the front.

They had left these plates on the block when i picked it up so I decided to take them off starting from the front RHS which had the oil line under it. This is what happened when i took the plate off............

[TuffRR]

As you can see from the photo, there is water streaming out of where the oil gallery comes up through the block to feed the heads (silicone is still partly covering the oil line).

Now I'm no mechanic, but i'm pretty sure water should not be travelling through the oil lines at all??????????