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1979 35 hp vibration

C

classicgen

Member
"I just installed this 1979 35hp Johnson on my boat and tried it out yesterday. First of all, 4-5 times I lost my prime on my fuel. I installed a kit in the fuel pump already, the loss of prime almost always occured at mid range speed, when at idle or full throttle it ran like a top. Maybe sucking air by a clamp on the fuel hose? Also at mid-range speed I got lots of vibration, is this common for this motor, the vibration was consistent 100% of the time. Thanks for any help.
Ken"
 
"That sounds like the throttle

"That sounds like the throttle roller cam is not synchronized with the spark advance, not a air/fuel leakage condition.

Notice the scribe mark on the cam that contacts the throttle roller. That mark should just touch the roller when it it dead center with the roller. This is the point where the throttle butterfly should just start to open, not before or after.

Now (engine not running), put engine in forward gear. Apply full throttle and make sure that the timer base under the flywheel is absolutely up against the full spark advance stop.

With the above set as it should be, adjust the brass (or steel) collar on the rod that leads from the vertical throttle shaft to the carburetor linkage so that the throttle butterfly is perfectly horizontal (full throttle).

Let us know if this cures the problem.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"Ok, I slowly pushed the throt

"Ok, I slowly pushed the throttle forward while in neutral and found out the throttle butterfly was opening way after the roller was past the scribe marks on the cam. I adjusted this by adjusting the throttle collar on the throttle shaft. So after I did that the throttle butterfly now starts to open just as the roller is in the center of the mark on the cam.
After this I put it in gear and then went full throttle, motor not running, at full throttle the throttle butterfly is perfectly horizontal. Does this all sound correct? Havent put it on the water yet, just curious if I did this correctly?
Thanks
Ken"
 
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