Oil pump covers leaking fix ?

[Spanielsam]

Hello
Having sorted my forks and steering bearings I now have the last annoying thing to sort before I am happy with the bike G80S 1956

I cannot stop the oil pump end covers from leaking, the threads in the crankcase housing are poor and I can only nip the screws up ( i wish I had sorted this when I had the engine out but was told not to disturb tne oil pump unless there was a problem which it later turned out there was )

Getting at the rear cover is very difficult and I know the correct answer would be to get the engine out again but is there any quick or temporary fixes that are known ?

I have tried with and without gasket cement and still no joy

I worry that if oil is getting out, air might be getting in

Thanks again

[Pharisee]

I had exactly that problem with my M18. The oil pump was feeding oil to the engine but not sucking it up from the crankcase. The problem was an air leak at the rear cover. Unfortunately, a previous keeper had put that cover back with slotted screws, not the correct hex head bolts. I couldn't get at them with a screwdriver so I bit the bullet and took the engine out. Actually, it was fortunate that I did. Only one of the screws was tight, two others were loose and the fourth was completely stripped. The stripped thread was repaired with a 3BA Heli-Coil insert. I 'refaced' both end covers with some fine 'wet & dry' paper on a plate of glass and reassembled with the correct bolts and a smear of blue 'Hylomar' on the paper gaskets. It's been fine ever since.

[56G80S]

I had a similar problem and the thread on one of the rear plate bolts is poor.

It's right up against the crankcase and I'd like to know how you managed the helicoiling. I did helicoil the head for the rocker box bolts but don't think I could take on this oil pump plate job.

My solution was otherwise like yours.

It weeps a bit (!) but supply and scavenging are OK and I've left it alone.

Spanielsam, it's worth a try before taking all out again, although I plan extensive work next winter need to enjoy this summer first.

Johnny B

[Pharisee]

It's right up against the crankcase and I'd like to know how you managed the helicoiling. I did helicoil the head for the rocker box bolts but don't think I could take on this oil pump plate job.

I entrusted the task to a guy that 'specialises' in thread repairs on vintage engines. I watched while he did the job. He'd made up an extension for the 3BA Helicoil tap which allowed him to use the tap wrench clear of the crankcase.

[Spanielsam]

Thanks for your comments although I was hoping for a magical self tapper or glue response 😄