Does a #13 carb jet exist?

[Brew2]

Hi all,

Wanted to do some experimenting and reduce the intermeidate carb jet on my 1986 Evinrude 140 from 16 (stock size per manual) to 13. After visiting the only two dealerships within a couple hours of me, I've had no success (neither dealership was willing to spend much time to help me).

So...does a #13 exist or am I chasing a ghost? If so, anyone got a part number?

Thanks.

 

[Brew2]

Re: Does a #13 carb jet exist?

^^

 

[Dhadley]

Re: Does a #13 carb jet exist?

I don't think there is a 13. There is a blank and then the first number is a 16, then 20, then they go up 1 number from there if I remember correctly. Anyway the jets are listed in the service manual by size and part umber.

Naturally this begs the question -- why do you need to richen the mid range?

 

[Brew2]

Re: Does a #13 carb jet exist?

Been chasing a bogging problem for a long time now. Compression and spark are both good. Motor "gets through" the bog if you bump the primer while accelerating, so reasonably sure it is a fuel problem.

Replaced every hose and clamp between the gas tank and the carbs...cleaned carbs numerous times...installed carb kits...checked side plate on all carbs.

Thought I had it solved when I increased the float height above level with the bowl. This reduced the bog to a slight hesitation for a trip or two, but now it is back to a regular bog.

At your suggestion and a last ditch attempt, I thought I would richen the intermediate jet to see what happens. Doesn't sound like that is feasible unless I order some blanks and try to drill them out.

The only other thought I had was to make all the intermediate jets the same. The manual, and therefore my motor, has one side at 16 (can't remember if it is starboard or port) and the other at 20. I suppose I could try 16 on all of them and see what happens.

Any other thoughts?

Thanks.

 

[Dhadley]

Re: Does a #13 carb jet exist?

Just for kicks, stick a toothpick in the mid jets and try it to see what happens. That will simulate blanks and if it helps you'll know we're heading in the right direction.

It may load up at idle but ignore that. Just concentrate on the bog. Get it on top, blow it out, reduce throttle and make a quick acceleration run to check the bog.

Never do this with the airbox cover off. You don't need all the bolts in the cover but you need the cover.