Author Topic: Oil leak from points cover  (Read 1131 times)

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Offline 38rudge

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Oil leak from points cover
« on: November 08, 2017, 06:12:39 AM »
I have an oil leak from the points cover. Looks to be gearbox oil?

Looking at the parts list there is an oil seal and an o-ring seal. Is either one more prone to failure?

In the case of the oil seal can it be removed without removing the cover and does anybody have the dimensions of the oil seal and the o-ring that are used?

Thanks

Andy

Offline Johnie

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Re: Oil leak from points cover
« Reply #1 on: November 08, 2017, 06:24:27 AM »
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline 38rudge

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Offline Deltarider

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Re: Oil leak from points cover
« Reply #3 on: November 08, 2017, 07:21:30 AM »
I have an oil leak from the points cover. Looks to be gearbox oil?

Looking at the parts list there is an oil seal and an o-ring seal. Is either one more prone to failure?

In the case of the oil seal can it be removed without removing the cover and does anybody have the dimensions of the oil seal and the o-ring that are used?

Thanks

Andy
What bike and has it sat for a long period of time?
CB500K2-ED Excel black
"There is enough for everyone's need but not enough for anybody's greed."

Offline flybox1

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Re: Oil leak from points cover
« Reply #4 on: November 08, 2017, 11:43:23 AM »
That oil seal has a ridge around it.  Ideally, you'd want to split the cases to replace it.
Its top right in this picture.

'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline PeWe

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Re: Oil leak from points cover
« Reply #5 on: November 08, 2017, 12:01:17 PM »
Or the o-ring around the advancer stud if lucky.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline flybox1

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Re: Oil leak from points cover
« Reply #6 on: November 08, 2017, 12:20:07 PM »
^^  I'd call that a victory!  ;D
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"