TR4/4A Oil leak from rear of motor.

[jimstr4]

Here we go again, there's a leak from the rear of the motor.
I've flattened and straightened the sump and used RTV to seal it onto the block.
I've used a Marx seal on the rear of the crank.
I wiped the area in the photo and watched the drop reform, it doesn't come from the sump.
I used a camera probe to look up between the flywheel and I don't think that the rear seal is leaking so I think that it might be the camshaft plug.
The camera probe is too large to look up the that corner of the motor.
The photo is a view of the rear slave cylinder side of the motor.
Looks like the gearbox has to come out yet again.

 

[TomMull]

There is also an oil galley plug just outboard of the cam plug. But the transmission and flywheel need to come out in either case.
Tom

 

[jimstr4]

Thankyou for the reply.
My repaired overdrive/gearbox didn't seem to work so I thought that there might be a second reason to remove the transmission.
So I decided that the prudent thing was to top the tranny up and put the car on stands and try the overdrive again.
It doesn't work.
Two reasons to remove the gearbox is better than one or not..........

 

[TomMull]

Since the removal of the OD gearbox is somewhat of a pain it would be good to get both issues done at once. However, there are some things you can check with the transmission still in the car and it might be better to know what the problem is before tearing it down. Here is a discussion from Moss and there are others:
https://www.mossmotoring.com/tackling-triumph-overdrive/
Tom

 

[jimstr4]

Thankyou for the reply.
I'll have a read and then work my way through the options.

 

[mallard]

With in inspection cover off I was able to get a small piece of a broken mirror that was taped to a rod to get a look up behind the transmission. I could see that the cam plug was indeed leaking. Easy fix with the trans out but the OD could be an other story. Good luck

 

[jimstr4]

By inspection plate do you mean the plate at the bottom of the tranny.

 

[mallard]

Yes the one that is like half a circle at the bottom of the bell housing.

 

[jimstr4]

The good news was that I got the overdrive going after adjusting the Solenoid/ lever.
MY son and I removed the gearbox afterwards.
Seemed alot harder this time, I'm not looking forward to putting it back.
I have attached photos showing that the leak was from the camshaft plug.
The dark crescent shape on the flywheel is oil.
There is oil on the bottom of the rear main flange which doesn't extend up to the bronze bush.
The bronze bush is dry.
I'm assuming that the rear main oil seal isn't leaking.
I'm also assuming that the oil got flicked around from the camshaft plug.
Hmmmmm??????
Any opinions would be helpful.

 

[Graham H]

It looks like the camshaft core plug is dry the leak looks to be coming from the oil gallery plug which is at 7 oclock to the camshaft

 

[TomMull]

It looks like the camshaft core plug is dry the leak looks to be coming from the oil gallery plug which is at 7 oclock to the camshaft

Agree. That plug is under pump pressure and is much more likely to leak.

 

[jimstr4]

Thankyou for the replies.
I thought the top one was the oil gallery plug, I got that wrong.
Yes the bottom one at 7oclock is leaking.
Is that a threaded Allen key plug.
Does mine look like a standard plug?
I've had a look at all my manuals but can't find any photos of that area plus I've looked at Moss Europe's online manual and they don't mention a part.
Neither do Rimmers.
If it's threaded I hope that it doesn't need retapping.

 

[jimstr4]

I've googled this problem and it seems to be a threaded aluminium Allen Key plug.
The only people who seem to list a part are Revington part no.: 056765
They suggest drilling out the old plug and using a threaded extractor which I assume will mean that metal swarf will end up in the engine necessitating the engines removal to clean the swarf from the oil galleries.
I'm hoping that mine will come out without drilling as the engine was recond.
I suppose that the thread might need retappng etc.
How have others fixed this problem

 

[jimstr4]

Moss-Europe seems to supply the following: [h=1]328-256 Plug, oil gallery ends, stick of 4[/h]

 

[jimstr4]

It's a steel plug and the threads look fine.
The gallery threads look a tiny bit scratched but nothing major.

 

[DavidApp]

A good quality thread sealer should do the trick. Or the brown shellac type gasket sealer on the threads. Clean the oil out of the gallery threads with solvent on a cotton swab/Q-tip.

David

 

[Graham H]

You should be able to re use that plug ,it just needs to be sealed,lock tight or PTF tape. Because its a parallel thread it hasn't got anything to lock onto,the original is a tapered aluminium plug that tightens as you screw it in.

 

[Graham H]

David you beat me to it.

Graham

 

[jimstr4]

It's the original plug, well it's the one that was on the engine prior to reconditioning.
The motor has been run a number of times without any oil leaks until recently, so the plug held for a while.
The parallel thread leakage makes sense.
I'm a bit paranoid as the current one took a while to start leaking and it's a pain to remove the tranny and put it back.
I suppose I'd have to reinstall it then attach the starter with short bolts to run the engine and test my repair.
I can buy a stick of aluminium ones I suppose.

 

[DavidApp]

It always amazes me how quick you can get answers from this forum.

This forum is a great resource. Not sure how people did it before the Internet.

David