Topic: Dam oil leak 550

[uksparky]

Came back from 60 mile ride today, and noticed a small oil leak, not a lot but it went around the back of the fins, at the cylinder block  base O ring left side i rebuilt the hole engine 4,000 miles ago using new parts and O rings, any one else had this problem, i can only think the heat of the engine caused the O ring to fail..

[Shtonecb500]

Honestly, every bike I see for sale on CL has oil stains on the fins. I can expect oil on the fins with any motor that has over 25k on it. That is usually the cause of an oil leak in that area though, failing oil ring. Did you use a cheap-o gasket set?

[dave500]

im with calj re torque the head.

[jaytee-nz]

Cal / Dave - do you recommend the 2 stage tightening process when the head is first torqued down after reassembly or only if it leaks ?
JT

[dave500]

I do two stages both times.

[flatlander]

torque down in 2 stages every time you reassemble the jugs/head. first torque to spec (in the pattern described in the manual, and gradually building up pressure to full spec). then leave over night. the next day, back off the nuts and re-torque the same way you did the previous day.

there's a thread on here buy a guy called branden: leak-free topend. search for it, it's a good read.

[strynboen]

is there a leak free 550?.mine is not drip oil..but you can see oil/dirt at the head

.mine is sveathing a bit..it started after 1000 km..all gaskets and o rings /pucks..ald sleightly bond araund the oil bores in the head..dont think it are the Work vorth to thange all Again..not before i can get some real good thik oil  puck..or some frost blow aut caps..to seal the holes..instead the rubber ones

[uksparky]

Honestly, every bike I see for sale on CL has oil stains on the fins. I can expect oil on the fins with any motor that has over 25k on it. That is usually the cause of an oil leak in that area though, failing oil ring. Did you use a cheap-o gasket set?

I used the NE brand gasket set $48-95   is that cheap- o  at the moment i am thinking i should have used  the Vesrah set.....i will re check the bolts but i am sure it a bad / fried O Ring
Thanks for the help guys

[strynboen]

i used vesrah..and renember that the rubber pucks vas more thinn then i liked..but took the thance..and it leaks light nov...

[MRieck]

Every surface should be decked or milled. Thousands of heat cycles on an air cooled engine will warp all the surfaces.

[uksparky]

Every surface should be decked or milled. Thousands of heat cycles on an air cooled engine will warp all the surfaces.

You are right about warpage, it's 40 years old, I checked the outer bolts they are tight, I am not loosening all the head bolts, that will disturb the head gasket seal, ran this morning for few minutes, no leak ...must only leak when good and hot and higher rpm..oh boy it gets hot..that leak point is under oil pressure, if slight blockage would that push the oil out.
Picture of base gasket not green color from oil stain

[dave500]

I take those head bolts to 18 pounds,loosening the bolts a little wont break the seal,just don't back them all the way off and thump the head with a rubber mallet.