Two acorn nut on bottom of engine

[bluerider79]

I have a 79 xs650. Does anyone know what the two acorn nuts on the bottom of the engine are. If my memory serves me correctly I believe they are between the two drain plugs and just behind sump filter cover. I thing they are leaking but if I remove them I'm wondering if I'm going to end up dumping oil.

 

[plattey]

If they're 12 mm, they may be case fastening nuts.

 

[Tim of DO THE TON]

They're just nuts holding the cases together. Check the torque specs. Remove one, replace the COPPER washer under it and tighten to spec. Then do the other one. I thought there was more than 2 of the 'special' acorn nuts on the bottom of the engine but I'm just going off memory. Check the parts diagram to confirm their locations.

These locations can leak oil, hence the use of copper washers which deform and seal the openings.

 

[bluerider79]

Thanks Tim. Sounds simple. I just finish with bike and cleaning. Changed oil and noticed leak. Just wasnt sure if I took them out if I was going to drain all my oil.

 

[5twins]

There are a few more at the front of the engine. I had to re-do those on mine. They weren't dripping oil, just "sweating" some out.

 

[bluerider79]

I may end up dumping all oil any way. I just finished replacing all seals on right side of motor and still leaking oil from bottom. The two acorns nuts and I think I'm leaking out of the back of the hump that is on the sump cover. Looks like it has a plug in the end of that may be leaking. Think I might take it off and jb weld around seam. Any thoughts.

 

[Jaydela180]

I chased an oil leak last summer and started with those acorn nuts. New washers and correct torque, but turns out that was just lowest point of engine and leak was elsewhere. Pretty sure leaking from starter to crank seal. Something to keep in mind

 

[peanut]

there are 6x of those acorn nuts on the bottom case . I've just ordered a set from Yambits .
I also ordered a new set of 9x M8 nuts in stainless with M8 copper washers ID8mm OD 14mm
There is also 4x long bolts with plain steel washers .
Might be worth replacing the lot whilst you're at it

 

[bluerider79]

I will try all advise given. I put new oil sump in and new gasket maybe I'm not tight enough on those bolt. Found a couple I could still turn eith a wrench. I'll find torque spec and tighten. Does anybody remember if those had a washer. My did not. Can't speak for someone else's work.