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1982 35hp Johnson main jet?

M

MNvoyageur

New member
Hi all, I've been lurking for a while, but I have a question that hasn't seem to have come up yet.

I've purchased a 35hp Johnson from a PO who was chasing down an air leak caused by not installing the gasket between the carb and in intake (?!). He had the mixture screw backed way out and went as far as to solder closed one of the holes on the throttle butterfly (again: ?!).

The problem that I have now is that the motor only idles well with the mixture screw all the way in: it seems rich overall. The carb on the motor is stamped 423023, which is similar part number to the late 80's carb models. It also has the primer instead of a choke which also supports late 80's model. The carb has a 70D main jet in it, which would be the correct main jet for a late 80's carb. HOWEVER, this motor is spec'ed for a 59D main jet.

My question is: If the carb is from a late 80's donor motor, should I be running the 70D main jet that those carbs are spec'ed with? Or should I switch down to the 59D that was stock with my engine (and maybe the carb is the correct one?)?

Float level is dead flat and about even with the top of the rubber gasket.

Thanks!
 
So it idles best with the needle screwed all the way in? There is something wrong besides the main jet. Yes the idle fuel does pass through the main jet, but is not metered by it. That job is done by the idle needle setting. Who knows what the previous owner did to it? He certainly thought he was a genius when he soldered that hole shut. Probably drilled out some other holes while he was at it.
 
fdrgator said:
So it idles best with the needle screwed all the way in? There is something wrong besides the main jet. Yes the idle fuel does pass through the main jet, but is not metered by it. That job is done by the idle needle setting. Who knows what the previous owner did to it? He certainly thought he was a genius when he soldered that hole shut. Probably drilled out some other holes while he was at it.
Click to expand...

Him drilling the carb body is not out of the question, that's a good point. If the main jet (easier/cheaper fix) doesn't solve it, I'll have to assume this is what he did...
 
The gap is set at .030. Would going to .040 make any difference here? It doesn't seem like a miss though.
 
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