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Discussion Starter #1
Just recently I had a timing belt failure caused so I am told when the metal bush on the tensioner/adjuster seized and the belt jumped a tooth and then partially sheared the belt.
Engine was dismantled to check for valve damage but pistons and sleeves where not touched.
Engine has been reassembled and started but mechanic says water is now entering the engine and draining in to the sump.
Is there a simple thing he has forgotten?
 

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Are you seeing a little bit of white sludge under the oil-filler cap? Run the car for a while and see if that goes away - it is VERY normal in a new rebuild to see SOME white build-up under the cap at first until all of the moisture inside of the motor burns off! Heck even after years of reliable running, you will sometimes see some early-morning white crud under the cap at first start-up every day during the winter, but it always burns off as the motor warms up and then goes away completely again!

OR - are you seeing lots of it on the dipstick and in the sump when you drain the oil!?

Is this a 5-speed car? How many miles? Were only the heads removed, or was the whole engine rebuilt?

If he had the heads off and at ANY TIME moved the car / bumped the car / rocked the car, or anything (while in gear), then there is a great possibility that some of the liners moved! (When you rotate the motor with the heads off, the pistons and rings will sometimes grab a hold of the liners and push them up out of position a bit!) Once the o-ring seal at the bottom of the liner is disturbed (separating the coolant up above it from the crank-case oil down below it), it is game over – they won't re-seal again – even with proper head-torque.

Now, there is a chance that he did the right thing and secured the liners with plates, washers, spacers and head-stud nuts while the heads were off and then he reinstalled the cleaned-up heads with new head-gaskets and it is still leaking... In this case I would replace the oil and filter, start the car and get it nice and hot and then - fast like a bunny - pull the plenum, the coil-pack cover and the valve covers and re-torque the heads warm!!! See if that helps!?

If it is still leaking then there was an issue with the preparation of the head-surfaces and / or the head gaskets! If those aspects up top are 100%, then you are looking at pulling the motor and starting over - this time with a fresh rebuild / clean-up of the liners, new o-rings at the bottom of the liners, proper preparation of the head mating-surfaces, new head-gaskets and the right torque - should be good. But, if he never even had the heads off for inspection / rebuild and it is suddenly mixing the oil and coolant, then it could be that you blew the head-gasket at some point! Keep in mind that the water-pump runs off of the same serpentine belt that drives the alternator, the P/S pump etc. If that belt stopped, or got cut and the thing got hot, you may have blown a head-gasket.

The short answer is that there are only two ways for water to get into the sump; head-gasket not sealing, or the liner o-rings not sealing. If oil is pushing into the cooling system (leaving little blobs of oil floating around inside of the coolant over-flow reservoir), then it is more than likely the head-seal that failed. Is it pressurizing the coolant bottle? In that case - head-seal for sure! (You can also do a chemical test to confirm oil-contamination in the coolant...) If the water is leaking down into the crank-case and mixing to a white sludge on the dip-stick, then it is more than likely the liner o-rings that failed!
 

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Discussion Starter #3
Auto transmission

Hello thanks for the info. Piston, liners and block as a whole were not disturbed. Car is also an automatic. Hopefully liners were not disturbed but as to whether he locked the liners in place, I do not know. I suspect not. The guy was workshop Foreman for the Alfa concessionaire before they left the country (Sri Lanka) so he should know better.
The heads were removed to check for valve damage, but these were okay. It took a while to get the parts down from overseas, btw forget Europe and the UK, Alfa parts are cheapest from the US, so the car has been out of commission for two months.
It is my daily runner, has c. 120'000 km on the engine and no matter whatever else I drive, nothing else quite fits... I called but found he had pulled the heads again so the best I can do now is make sure he prepares everything properly prior to reassembly. I personally think - after reading these forums that he has had an o-ring failure. I will print out your response and give it to him and let you all know how it all panned out.
 

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Discussion Starter #4

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Sorry forgot to clarify, coolant is draining into the sump.
Chances are as JJ stated one of the piston liners moved and broke a liner rubber oring between liner and engine block because liners were not locked down with special large washers, holddown tubes, washers and nuts on head studs when heads were removed and crankshaft was moved. Moving crankshaft will raise piston and rod and can move the piston liner.

You need to remove sump (oil pan) pressurize coolant system and see which piston liner seal is leaking.

Repair requires engine disassembly and removal of liner(s) and replacment of rubber oring seals.
 

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Discussion Starter #6
Liners and pistons were locked

Mechanic says he locked down pistons and liners as per JJ & Steve said he should have. He is nonplussed but perhaps we will know more later today as he has taken the heads off again. More anon. fm
 

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So, what was the outcome...?
 
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