1987 140 v4, Jetting Question and clarification please !!

Per my manual I need to jet as follows..
ORIFICE, intermediate, No. 16, starboard. 140 Models With 397908 Stamped in Cover Plate. (My configuration)

Physical layout of cylinders standing on the ground looking at the engine port=left starboard =right ...

Port cylinders 2<<<<>>>>>1 Starboard side
Port cylinders 4<<<<>>>>>3 Starboard side

Question is do I install the .16 jets this on the Starboard side of the engine which is cylinder 1 & 3 or 2 & 4 ?
 
you need all jets same for every cylinder or you'll loose one of your cylinders from leaning out.

my mains are all 62

the low is 16

the high is 56

i'll recheck the jet sizes. that's on a 1988 J/E 140
 
you need all jets same for every cylinder or you'll loose one of your cylinders from leaning out.

my mains are all 62

the low is 16

the high is 56

i'll recheck the jet sizes. that's on a 1988 J/E 140

I am confuse please see attach clip it shows for the intermediates .16 for Starboard and .20 for port
The confusion or its me just over analyzing? I installed the .16 on the Starboard side .20 on Port side as instructed in my manual I may be right or I may be wrong just wanting to be sure ....
Do I install the jets base on cylinders location or port and starboard in regards to Boat ? remember the port carbs feeds the starboard cylinders and the starboard carbs feeds the port cylinders...I see this stuff posted on various sites with no clear answer, they have to have an engineering fact in there somewhere I hope, bare in mind its the same bunch of engineering genius at BRP who figured plastic carbs was the wave of the future:) Just ask Destroyer !
 

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I know the catalog calls for the 16's on one side and 20's on the other, but I would reccomend going with 14's or 16's in all of them. I jetted mine this way origanally because that is what the manual called for, and it kept stalling when I would come off idle. Went to 14's in all 4 and she purred like a kitten.
 
Thanks Ferm I will give that a try, I was running .20 in all the intermediates and it was doing exactly what you describe consistent after a long trolling,
At first I thought it was old fuel, however I ran it empty and try fresh fuel and even clean the carbs....Last weekend I was out in rough waters and she kept stalling when getting up on plane. If stab the throttle she jumps up and run like a rabbit... its why I am trying to figure out the jetting ...I am stock on idle and high ...I will post the results ..
 
Thanks Ferm I will give that a try, I was running .20 in all the intermediates and it was doing exactly what you describe consistent after a long trolling,
At first I thought it was old fuel, however I ran it empty and try fresh fuel and even clean the carbs....Last weekend I was out in rough waters and she kept stalling when getting up on plane. If stab the throttle she jumps up and run like a rabbit... its why I am trying to figure out the jetting ...I am stock on idle and high ...I will post the results ..

Yep, all 16's or 14's will take care of that. OMC was experimenting early on with how to get these loopers to run, and 85-87 went through ALOT of changes for these reasons.
 
Ferm, I change the intermediates to .16 from .20 low and behold the shutdown/stuttering from idle up to a plane is gone!
However I observer she now has the FLU, she is sneezing on idle ! I was thinking to richen the idle currently .28 to maybe a .23 ?
Remember I have the Boy's reeds installed ...
 
Ferm, I change the intermediates to .16 from .20 low and behold the shutdown/stuttering from idle up to a plane is gone!
However I observer she now has the FLU, she is sneezing on idle ! I was thinking to richen the idle currently .28 to maybe a .23 ?
Remember I have the Boy's reeds installed ...

That sounds about right, but make sure your BOYESENS aren't leaking any at idle as mine were with only 4 hours on them. CHanged over to the TDR reeds and no more sneezing when I had my 225.
 
Thanks I will give that a try, My gut feelings tells me you are right on about the reeds leaking. I have a complete set of CCMS reeds which Chris personally installed and sent to me. Just in case this idle does not improve i will swap them out.
 
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