10 replies to this topic

[elliot341]

Please can people assist me with the appropriate method of engine plate removal. I have an oil leak which I have identified as coming from behind the engine plate.

I am confident that the leak is coming from here as I have cleaned the engine up multiple times, ran the engine and been able to rule out a leak from the driveshafts, tappet chests, timing chain cover etc. The leak is weeping between the top/back of the engine plate and running down the block, onto the driveshafts etc.

Please could you help me with understanding what I need to do to get to the engine plate. I'm reasonably happy to strip out the rad, hoses, water pump (which was replaced during the resto), but beyond taking the timing chain cover off I'm new to this bit.

I believe I will need to support the engine on a jack/stand and undo the engine mount on the rad side, I'm unsure beyond that what tools I will need or what I need to do to get to the engine plate.

Could you outline what I need to do and how i need to do it? I believe I need to lock the engine/flywheel/cam shaft but also remove the cam shaft pulley and any other pulleys there. If you could let me know what I should replace (gaskets / seals etc). The engine is only a 998 with a stage 1 kit so im not necessarily looking to upgrade anything for extra power etc.

Realistically id like to do this with the engine in situ if at all possible.

Any assistance would be greatly appreciated. Thanks

[nicklouse]

There is nothing to leak from that area other than thrown oil. There is an oil gallery plug.

 

as to how. Engine out or engine in? You do have a Haynes workshop manual to refer to as well?

[Earwax]

The inner ( engine side) of the plate as said by Nick id not a "usual culprit' for oil leaks ( or ever in my experience).  

 

AS also named by Nick, , the oil galley plug can be a culprit - depending on whether a 2 plug or 4 plug block these can sit very close to or partially under the engine plate ( I have done a little sculping on the engine plate of one race engine to allow for in situ remediation until the next build fixed the problem) The location of the galley ,,,, when facing the timing cover from the radiator side, the quadrant from 6 oclock to 9 oclock is where it will be) Again in situ even if you can access it - due to weeping oil I recommend doing the galley plugs properly with a good amount of time for curing.

 

Timing covers can be replaced in situ - but I have done a poor job of one like that and in the  end pulled the engine -  The inner facing timing cover nuts are a pain to get to - and although they don't need much tightening I was too slow to get to all whilst my gasket plus 3 bond sealant hardened and or i did an awful job of cleaning the faces and or I didn't lightly tap the timing cover base to straighten the edge 

 

If you want to treat your beast to some straight edges - timing covers and engine plates are available _ NOT REQUIRED at all but an option...

 

 - and some of the "new aluminium replacement engine plates"  ones come with posts and nuts facing outwards - making them easier to fit in situ  ( alas I think some reverted to metric threads on these small nuts which to me is close to heresy on a mini)  These are NOT REQUIRED at all - but are lighter ( not really a game changer) and straight .

 

NOW with all things bought new these days don't assume they will fit perfectly - you may need to further countersink the 2 holes that sit under a double row chain ( well they sit under a single row too)

[nicklouse]

Oh, I would suggest some UV leak detector additive into the engine you you can be 100% sure of where the leak is.

[elliot341]

Does anyone have any decent photos of this area of the engine? Stripped or partially stripped? Altho I'm 100% sure the oil is running down between the back of the engine plate and the engine, it would help to try n understand a bit better. Thanks for the replies so far

[nicklouse]

Have a look in your Haynes workshop manual. Good pictures in there.
1275 block?
Wrong end opps try again.

 

not got any as nothing really happens there.

Edited by nicklouse, 26 July 2023 - 07:00 AM.

[JXC Mini GT]

I had a leak on my mini from behind the end plate, that was solved by replacing the half moon seal between the gearbox and engine.

[elliot341]

I had a leak on my mini from behind the end plate, that was solved by replacing the half moon seal between the gearbox and engine.

where was the oil leaking out? the bottom of the engine or out the top/back?

[JXC Mini GT]

It was hard to tell, when the engine was running I couldn't see where it was coming from other than in the region of the plate lower down. I decided to bite the bullet and replace the timing cover oil seal timing cover gasket, plate gasket and half moon seal, now I have no leaks. 

Good luck

[Cooperman]

If it is coming from behind the engine front plate, it may well be the half-moon main bearing cap seal.
It's not too difficult to get the front plate off once the timing chain cover and timing gears/chain have been removed.
I had to fit a new plate when the alternator mounting lug fractured and it took me a morning to do it.
Once the plate is off you will be able to see both the seal and the oil gallery plug.

[elliot341]

Sorted! Needs a new head gasket, i just hadnt been able to pinpoint the exact location of the oil leak up until this lunchtime. Thanks