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New Main Seals, Pilot Bearing replacement and Oil Pump

When I removed the bell housing on this engine, there was evidence of a leak from the rear main seal.

To gain access it's necessary to remove the flywheel first:


Which I sent off to have lightened and balanced along with the pressure plate. With the flywheel removed you get access to the rear of the crankshaft with the main seal and pilot bearing into which the drive shaft is inserted.



There's a small rectangular recess at the bottom of the seal below the crankshaft - there was oil in there which lead me to believe that's where the leak was originating from. Reading various sources about rear main seal leaks and fitting replacements, it appears to me that the reason this particular one was leaking was because the seal it's self wasn't seated against the machined surface behind it, leaving a small gap for oil to escape from, primarily from the small rectangular hole. That's my theory. 

Anyway I decided I would remove it and replace it, inserting it so as to ensure it was flush with the machined surface at the back - seen in the pic below.


With the recess all cleaned up I pressed in the new seal. To help with the refit I placed the seal in the freezer for a while (along with the pilot bearing) before giving it a thin coat of oil to help it slip into place. Not having a special tool I used the old seal as a press to push the new one into place - 


this time I pressed the Porsche rear main seal all the way back and didn't leave it flush with the casing - it's now marginally set back and up against the machined surface at the back.


To remove the pilot bearing, place a small bolt into the hole with vice grip attached



 - then gently hammer on the vice grip to pop the bearing out:



Half an hour in the freezer was enough to help the new pilot bearing into place with some more gentle encouragement from a rubber mallet...


Onto the front oil seal which is housed in the oil pump on the other end of the crankshaft.


Remove the old seal with a seal pick and gently press in the new one - once again I used the old seal as a press to push the new one into place so it wasn't damaged:


The new oil pump (below compared to the existing one) I was installing had been refurbished apart from a new seal:


Loctite 574 is the Porsche stated sealant of choice for machined surfaces - I managed to source some from eBay after none of the local motor factors nor Halfords stock it - it's less than £10 a bottle and is used else where including on the balance shaft housings.

With both the engine and oil pump mating surfaces cleaned I applied the Loctite...


...and slid the oil pump over the crankshaft then torqued (10Nm)) the bolts down before slipping the splined insert and washer into place.


Job done. New front and rear main seals, pilot bearing and oil pump installed!
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