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85hp V4 1974 Johnson- new throttle cable, made some adjustments, trouble starting/running

K

kippstakes

Member
So I think I might have gummed up the timing on my motor, or maybe the idle throttle- I don't know.
Three days ago she started up without any trouble, and ran like a top. Compression is perfect, solid spark on all four.

What happened was I was having trouble getting the throttle up to wide open- the control lever seemed to bottom out around 1/3 throttle. I tried compensating by adjusting the throttle at the throttle cam (which I now realize was a mistake). Turns out, after splitting the control box, my throttle cable was just binding. Luckily I had a replacement on hand, which fixed the binding problem once installed.

HOWEVER, when I went to start her up today, it would only occasionally sputter a bit and then die, and barely that. I must have screwed something up with the timing or the start position on the cam.
Update: I adjusted the cam plate so that there's a hair of space bt it and the throttle roller. After some cranking, lots, she finally and grudgingly started up. It seems to run a little rough now tho, or maybe I'm just being overcautious.

Any ideas??

Here's a vid for reference.

https://www.youtube.com/watch?v=XIQa...dIfwUA&index=1


Thanks!
 
The thing you adjusted?..... Are you speaking of the threaded nylon connector on the arm that extends between the vertical throttle arm and the metal cam that rolls against the throttle roller?

If so, you'll need to set the idle timing to whatever it states in your service manual (somewhere between 2-5 degrees). Any guess work could prove expensive.

Full throttle adjustment...........

1 - Make sure that with the cam NOT touching the roller, the linkages between the carburetor throttle butterflies are set so that the butterflies open and close at the same time and close completely at idle. You DO NOT want one butterfly ever so slightly open while all others are closed.

2 - With the idle timing set properly, set the throttle roller so that the scribe mark on the cam is dead center with the roller when the butterflies just start to open.

3 - Adjust the throttle cable trunion so that the butterflies are fully open (horizontal) when at full throttle. If it is possible for the butterflies to go beyond horizontal... that is they start to close when continuing to apply throttle (some carburetors do that), set the mechanical stop to prevent that happening.

Hint... When tinkering, take pictures and make clear notes before doing whatever as a back up. We think we'll remember those goofs.... it doesn't happen!
 
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