Trying to figure out carbs on a 1993 120 looper

reddragon72

Cadet
Joined
Aug 30, 2020
Messages
13
I have a 1993 Johnson looper that I cannot figure out why it wont idle. J120TLATF
The carbs on it are 435947 part number with 37 top and 30 bottom for the idle and mid air fittings.
One carb has those fitting backwards and I cannot get the bottom one out it turns the whole brass fitting in the carb.

I decided to look up the carb for a replacement and https://www.vansoutboardparts.com/e...1832?trail=224279,387646,441489,441830,441831
says the carbs are supposed to be 0436285 not the 435947 that is one it (all four are that number BTW and all four have the same numbers for the brass fittings.

So what is the difference here? I clearly need a new carb, hoping that fixes the issue but what am I supposed to order?

Any help would be greatly appreciated. Thanks
 
Joined
Jan 17, 2019
Messages
946
how do you figure they are backwards? remember, these are for AIR, so the larger the orifice, the leaner it gets. fuel is opposite. the easiest way to tell is if the jet is vented ie. pointing straight out to atmosphere. fuel jets are metering fuel by fuel passing through them, air jets / bleeds are doing the same thing just sucking air.
 

reddragon72

Cadet
Joined
Aug 30, 2020
Messages
13
These are the tiny ones on the front of the Carb. They are for air but I have read so many posts about these things that they always seem to go smaller number for idle then larger for intermediate and then biggest for main. I thought it was odd that the site showed the idle and intermediate as the other way around.

I'll swap them like the site shows and go from there.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,932
Depending on carb series and shaft length Intermediate is always a few sizes smaller than idle. You need to flip your jets if 30 is in the bottom
 

reddragon72

Cadet
Joined
Aug 30, 2020
Messages
13
I flipped them. I think I have found a possible issue. The plate on the side for the air-fuel mixture for idle and mid has a leak on two carbs in the upper back corner. I decided to spray some carb cleaner through them with the air mixture screw closed and it sprayed out there like crazy on two of the four. I have new kits on the way that I hope fixes it.
 

reddragon72

Cadet
Joined
Aug 30, 2020
Messages
13
Alos found the two nuts on the studs on the 1,3 carbs were seriously loose. I tightened them and put on the new carb gaskets in the rebuild kit. It idles and barely coughs now but idles at 11oo RPM and fluctuates to 1300 then back down. I think I am getting really close now.
 
Top