Worst AU coolant leak

[PridenJoy]

Thought i would start a thread on an issue i have dealing with on my wagon in the last few days.

On the way back from a long distance holiday, noticed the header tank was empty. Looked under the car and noticed a rapid coolant leak coming from towards the back of the motor. Credit to the car and the bullet proof AU engine, car got us home fine after a couple of water top up stops, which we would have made anyway.

Once home i thought I'd get underneath the car, hoping this leak is as simple as a hose or a water tap crack, the leak is very rapid, it drops lots of water in very short time, here is what i found.







Just in the 5 minutes i had the car up on hoist it leaked this much water.



Leak was coming from between rear of engine and transmission bellhousing, this indicated it is most likely coming from the welch plug at the back of the motor (bad spot for welch plug Ford) which can only be accessed once auto and fly wheel are removed. Bugger.

Here is the welch plug in question shown on a motor out of a car. It's hiding behind the Ford Engine operations sticker.



Car has close to 400k kms so i contemplated replacing the whole motor while I'm at it but decided to persevere with this one.

So the job was on. Tailshaft out. I marked it with a texta so i can put it on same way.







Next the exhaust needs to get out of the way to remove the auto. There is no need to remove whole exhaust, just factory Cat. Then get exhaust out of the way.

Supporting the exhaust





Cat removed





Transmission mount bolts undone. At this stage it's wise to place a jack under the auto to support it.



Transmission lines and electricals undone



Undo T bar linkage rod



Lower the jack gently to drop the rear of the auto and expose top bellhousing 19mm bolts





Also place an oil pan underneath the rear of the auto in case transmission fluid drains out of the rear once it's lowered





This is what i use to access those top 19mm bolts. The uni jointed socket is very handy.





All top bolts are out, only ones left are bottom 13mm ones which are easy to access as well as torque converter bolts. Raise the transmission so that it's level again to take the pressure off remaing bolts.



Next the torque converter to flywheel bolts. Remove inspection cover on back of engine and you're greeted with this. If not rotate the front of the engine with 22mm socket until you see one of the bolts.





There are four torque converter bolts, rotate engine to access them and undo one by one.

Next the bottom bellhousing 13mm bolts



Now all bolts securing engine to transmission are removed, it's a matter of man handling the auto to separate from the engine.



Lower the jack with the auto on it and move it to the side.


Next to remove is the flywheel, six bolts are easily undone.





And the problem is now exposed







I knew removing the plug would involve getting a shower with coolant and i didnt want to drain the whole system yet so i put a hole in it to drain first





Then hit one side of it with a hammer and pulled it out.







You can see all the pinholes in it caused by corrosion



Lots of cleaning up to do





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