1990 140hp jets wrong?

[archcycle]

Cleaning out the orifices on my 1990 johnson 140 I found the idle bleed jets are wrong.

http://www.boats.net/parts/search/BRP/JOHNSON/1990/J140TLESE/CARBURETOR AND LINKAGE/parts.html
This has the idle bleeders as #41 but the ones I have are 36, and the bottom starboard looked more like 39 (stamped off center) but I can't find any 39s in parts lists so I'm just going to assume it's 36 as well.

The 1984 Johnson 140 has a 36 jet but it's clearly not my carb.
http://www.boats.net/parts/search/BRP/JOHNSON/1984/J140TLCRD/CARBURETOR/parts.html

Is this a problem?

 

[archcycle]

Re: 1990 140hp jets wrong?

Just bought a screwdriver that would fit in the HS jet hole and at least all of the high speed jets are 63D. That and a pair of fine tip needle nose pliers did the job in place of the OMC tool or cutting off the shank on a driver just fine. So that leaves just 4 jets that are not what the parts list says.

 

[cdn-pk]

Re: 1990 140hp jets wrong?

my 86 120hp has weird jetting too. two carbs have 37 the other two have 39's the others are all 16's and the high speeds are the same.

i made sure the carbs went back from where i took them off. i never really looked into why as she runs fine, but it is a very curious question.

 

[archcycle]

Re: 1990 140hp jets wrong?

I never really kept track or monitored the spark plug condition other than giving them a pass/no pass. That's probably going to be the only way to figure out if this was set up this way for a reason. I'll take some pictures after I run it this weekend. It's spent a lot of time idling on the hose lately due to some other maintenance so they're probably not showing very honest characteristics right now.

 

[archcycle]

Re: 1990 140hp jets wrong?

my 86 120hp has weird jetting too. two carbs have 37 the other two have 39's the others are all 16's and the high speeds are the same.

I would like to know where those 39s come from..

 

[archcycle]

Re: 1990 140hp jets wrong?

Still haven't gotten around to buying new jets.

I've done a lot of searches on here and google and found loads of posts saying that OMC made lots of updates to their recommended jets, never got them right, service bulletins, etc etc etc but have not come across any specifics. I've seen nothing that could be taken as more than internet junk.

There is no 'in 19XX OMC began to recommend XX orifice in XX bulletin' in any of the many posts I've read.

Does anyone know anything about any actual OMC changes or bulletins?

 

[archcycle]

Re: 1990 140hp jets wrong?

Update:

Some other topics of jets on here lately got me thinking my old idle jet issue needed addressing so I finally bought the new #41 idle bleed orifices and installed them this week and it made a huge difference. Some other reading said that Boysen reeds require you to drop 5 sizes on the idles so I wonder if my carbs came off of a motor that had them considering that I know it's frankensteined hard. Honestly I don't know if it maybe has Boysens in it but you'd think that if it did then it would run better with the 36s..

Now coming off of WOT it idles perfectly as opposed to before where it would take a bit before it wanted to idle right after a WOT run and would die here and there but would come back after running around 1400 for a bit. Also it would sometimes idle great for several minutes then with no sneeze or dramatic effect would just sort of die out. This was a serious problem trolling. No more.

Two trips with the new 41s and it has idled perfectly no matter what I'd been doing and is smooth and quiet at 650rpm in dead idle Forward gear. Its strange that it loves 650 which is significantly less than what the manual calls for but that's an issue for later.