Author Topic: Possible Diagnosis for Oil Leak?  (Read 1335 times)

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Offline evinrude7

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Possible Diagnosis for Oil Leak?
« on: May 24, 2017, 10:59:19 AM »
Not planning to tear into the motor until next winter. This is a photo of the header for #3 cyl. With the oil up where the header meets the motor what could be the cause?  I do tend to get serious popping on decelerating and a fair amount at idle from #3 however I'm far from a well tuned bike. Oil level doesn't change much but the caked up oil by header is somewhat wet.                                 

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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Possible Diagnosis for Oil Leak?
« Reply #1 on: May 24, 2017, 11:17:12 AM »
Usually cam tower puck or stud leaking. If you have a frame kit it can be repaired without removing the engine. Otherwise it turns into a much bigger job. May be a good investment even for a 1 time repair.
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Offline flybox1

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Re: Possible Diagnosis for Oil Leak?
« Reply #2 on: May 24, 2017, 11:22:11 AM »
Pucks.
Oil + Exhaust gasket leak.
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Offline evinrude7

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Re: Possible Diagnosis for Oil Leak?
« Reply #3 on: May 24, 2017, 12:11:40 PM »
Usually cam tower puck or stud leaking. If you have a frame kit it can be repaired without removing the engine. Otherwise it turns into a much bigger job. May be a good investment even for a 1 time repair.
Pucks.
Oil + Exhaust gasket leak.

got it.  thank you. 
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Offline evinrude7

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Re: Possible Diagnosis for Oil Leak?
« Reply #4 on: May 24, 2017, 01:31:11 PM »
wondering if i should tackle this now.  carbs are off the bike for cleaning and rebuild.  sending my regulator out for repair.  when i get the carbs on the vreg back i'm still going to have tuning issues because of the exhaust leak. 
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Offline flybox1

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Re: Possible Diagnosis for Oil Leak?
« Reply #5 on: May 24, 2017, 01:53:25 PM »
I dont like to rush stuff, but yes, it can be done in a weekend.
Easier if a frame kit is installed.
'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
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Offline calj737

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Re: Possible Diagnosis for Oil Leak?
« Reply #6 on: May 24, 2017, 02:01:26 PM »
Probably time to replace the exhaust crush gaskets too  ;)
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Offline evinrude7

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Re: Possible Diagnosis for Oil Leak?
« Reply #7 on: May 24, 2017, 02:38:00 PM »
Probably time to replace the exhaust crush gaskets too  ;)
I dont like to rush stuff, but yes, it can be done in a weekend.
Easier if a frame kit is installed.

if i do it i'm not going to rush it.  sorta like do i bite the bullet and do it now or ride it til next winter?
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Offline flybox1

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Re: Possible Diagnosis for Oil Leak?
« Reply #8 on: May 24, 2017, 02:41:02 PM »
ride...and keep your oil topped  ;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

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1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
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Offline Duanob

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Re: Possible Diagnosis for Oil Leak?
« Reply #9 on: May 25, 2017, 10:26:08 AM »
Curious, but it doesn't look like it's dripping. Does it burn off the exhaust or smoke? If it's just a sludgy build up (slow leak) it could probably wait til winter time. I know the 550s are notorious for leaking at the sides of the engine between the head and jugs, most cases the bike will last forever if the oil is kept topped up without fixing it. I fixed mine just for appearance-sake. I don't like oily engines.
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Offline cb

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Re: Possible Diagnosis for Oil Leak?
« Reply #10 on: May 26, 2017, 05:40:31 AM »
What is a "frame kit", please?

Offline evanphi

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Re: Possible Diagnosis for Oil Leak?
« Reply #11 on: May 26, 2017, 05:45:21 AM »
What is a "frame kit", please?

Stage 1 of frame cut/top end work...

Marked the spots


Cut them with a tube cutter to give a guide for the hacksaw. Covered the engine after threading the saw... and decided it was too cold to start getting in to this now. Bringing the space heater to the garage tomorrow.



I cut just above the carb linkage, and all the way forward allowing for the ignition bracket.




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Offline evinrude7

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Re: Possible Diagnosis for Oil Leak?
« Reply #12 on: May 26, 2017, 06:23:01 AM »
Curious, but it doesn't look like it's dripping. Does it burn off the exhaust or smoke? If it's just a sludgy build up (slow leak) it could probably wait til winter time. I know the 550s are notorious for leaking at the sides of the engine between the head and jugs, most cases the bike will last forever if the oil is kept topped up without fixing it. I fixed mine just for appearance-sake. I don't like oily engines.

wouldn't say it's dripping.  shiny which means wet.  i'm not too worried about it.  no major smoking.  i plan to ride it for the rest of the year.  i do have a slow leak at the bottom left side of motor as well.  hoping to address all issues this winter.  right now i've got the carbs pulled apart again and the regulator going out for repair.  fixing all the easy things on the bike at the moment, as time and $ allows. 
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