Refitting flywheel on a Perkins 4 - 108

[Hunter34]

I have just removed the gearbox from my 4 108 to renew the forward clutch and while it was off I was hoping to replace the rear crankshaft oilseal which lives behind the flywheel.
My manual indicates that after a major overhaul it is necessary to use a workshop tool to center the flywheel and housing.
As its not a major overhaul I am tempted to mark the position of the flywheel and housing and take them off to get at the seal.Then I could just reset everything where it was.
Has anyone else tried this?
I would hate to bolt bthe thing back together and watch it bounce around the engine room when I start it.

Thanks

Andrew

 

[sailorman]

well i changed the antiquated ( design that is )seal on my old 4108 no probs didnt see any thing to line-up. soak the string in engine oil overnight prior to assembly

 

[Lakesailor]

On a vehicle with a dry clutch plate you would need to centre the driven plate with a mandril in order to get the gearbox input shaft to enter right through to the bush in the crankshaft end.
The manual isn't from an automotive application is it?

 

[Hunter34]

No the maual is for a Perkins 4 - 108 marine diesel engine - Not a car!
For those who do not know the manual has instructions and photos of how to use a workshop tool to center the flywheel before tightening the bolts to hold it in place.
Apparently if not centered properly it will not run true and slowly distroy the crankshaft bearings and gearbox bearings too.

 

[Lakesailor]

"The manual talks about checking alignment of the adpt. plate, flywheel, and flywheel housing. I did not have any alignment problems. All the pieces have alignment dowels. I did check with a dial indicator though. Make sure the new shaft seal material meets where the two halfs come together and use some gasket sealant behind the aslb. where it bolts to the engine block. Its not hard. "

Spotted this on a Morgan 38 Owners forum

I thought there must be something to align the flywheel. I've never seen one that relies purely on the grip of the bolts. If you are bolting down onto dowels (or a taper) it's wise to go bashing all around the circumference with a heavy mallet and then try nipping the bolts up some more. It's suprising how much you'll get.