Question regarding lower crankcase acorn nuts

AZscrmblr · Post by **AZscrmblr** » Wed Oct 18, 2017 4:31 pm

I am getting ready to split the cases on my CL77 and have a question about where the two 8mm acorn nuts go on the bottom of the lower crankcase. I thought they were the two center nuts of the four 8mm nuts at the front of the engine. On my engine they are the two outer 8mm nuts located to the left and right of the oil pump. I want to make sure I put them back in the correct location when I reassemble the cases.

AZscrmblr · Post by **AZscrmblr** » Wed Oct 18, 2017 5:50 pm

I think I found the answer when I searched on cap nuts instead of acorn nuts.
They should be the middle two 8mm nuts of the four at the front of the engine. Can someone please verify.

Thanks

LOUD MOUSE · Post by **LOUD MOUSE** » Wed Oct 18, 2017 7:45 pm

You are correct. ...............lm

AZscrmblr wrote:I think I found the answer when I searched on cap nuts instead of acorn nuts.
They should be the middle two 8mm nuts of the four at the front of the engine. Can someone please verify.

Thanks

DJM · Post by **DJM** » Thu Oct 19, 2017 2:35 am

Correct answer as would be expected from LM, the real question perhaps should be
'Why are the acorn nuts on those two studs in the first place?'

As far as I can see they serve no purpose and the two front centre studs are no more likely to leak oil than any of the other crankcase studs with the obvious exception of the 6mm stud which passes through the main oil gallery which has its own aluminium sealing washer and cap nut.

Ideas anyone?

LOUD MOUSE · Post by **LOUD MOUSE** » Thu Oct 19, 2017 7:25 am

I only suspect without any other proof that because HONDA installed the COPPER Crush Washers there that HONDA felt or found a tendensy to leak oil at those studs.
The CAP NUTS were discontinued some time in 1967 same with the 4 center nuts on the head. .............lm

DJM wrote:Correct answer as would be expected from LM, the real question perhaps should be
'Why are the acorn nuts on those two studs in the first place?'

As far as I can see they serve no purpose and the two front centre studs are no more likely to leak oil than any of the other crankcase studs with the obvious exception of the 6mm stud which passes through the main oil gallery which has its own aluminium sealing washer and cap nut.

Ideas anyone?