Carb ?

jenoble01

Petty Officer 3rd Class
Joined
Sep 6, 2006
Messages
88
Having trouble with my engine(sure some remember it). It's a j225TLERK that's stalling when in gear at idle. I have been going through all the troubleshooting steps and have reached the point of pulling the carbs apart. All the carbs were clean looking through the idle orifices. On one carb I found that the high speed jet had backed out of it's housing and was just laying there in the gap between the float bowl drain and where the orifice should be. This bowl was also fairly dry compared to the others. Could this possible be causing my idle problem with fuel leaking out somewhere or even causing a cylinder to run way to rich? I have a hard time believing it would cause my issue but guess it's possible. Also, does anyone sell gasket kits for the carbs? I don't need the needle valves, floats etc. Just want to replace the gaskets as I found a couple I suspect are leaking, but it could be spillage from disassembly and it probably wouldn't hurt to replace them anyone as the engine is a 94 and from what I've found so far they've never been apart. I suppose i could take another's advice and cut my own as he did. Thus far I've replaced the primer bulb, fuel line(looked pretty rough), rebuilt fuel pump because it failed pressure test outlined in manual, am currently running on premix remote tank to ensure the vro is functioning properly, compression checked out at 90-95 across all cylinders. Once I get things running properly I plan on doing a decarb as the pistons are slightly carboned up. So what's everyone think about the loose high speed jet?
 

bds85466

Petty Officer 1st Class
Joined
Jun 11, 2007
Messages
375
Re: Carb ?

Since the jets are the mechanisms that let the gas/oil into the air tunnel, anything that might be out of order could be causing a problem with the overall carb performance. If your loose jet changes the overall dynamics through the carb, it could very well be causing a problem.

As flow rates increase, either the venturi -- "the air tunnel" of the carb -- or the jet, or both, will begin to "choke"-that is they reach a point where the flow rate will not increase, no matter how hard the engine tries to pull air through. At the other extreme, when the velocity of the air in the venturi is very low-like at idle or during startup, the pressure drop across the jet becomes vanishingly small. It is this extreme that concerns people with respect to starting, idle and low-speed throttle response.
 

jenoble01

Petty Officer 3rd Class
Joined
Sep 6, 2006
Messages
88
Re: Carb ?

Well my engine ran great for a short time. The stalling problem was non-existent. We made a short run to the other end of the lake and were idling through another no wake area. Engine lean sneezed and died. So now I have another problem to look into. It started running very rough, when I went to take back off it stumbled then died. Any ideas where to start? I'm thinking either my carbs are leaking air(need to order gaskets), or my plugs fouled, running a mix of oil, gas and seafoam in a remote tank. It was pretty much dark when we got home so haven't' had time to do any checks yet.
 

bds85466

Petty Officer 1st Class
Joined
Jun 11, 2007
Messages
375
Re: Carb ?

You may have some sort of gasket leaking, but I would wonder if a bad gasket like that would set on in this manner? You should send a private message to tashasdaddy and ask him if he's seen this thread. He probably has a lot of great ideas for possibilities.

I'm not an expert on motors, but I think the easiest, most reasonable place to start would be the plugs (assuming you haven't already). They're cheap/easy to replace and you can get some good information about how each cylinder is running from the condition of your spark plugs (fouled, greasy, etc).

I have a 71 johnson and I had a similar problem stalling when I tried to go from idle to mid throttle...it would sputter and die. My motor required a lot of tweaking with the clutch etc to get it just right. I did some carbon clean up and it helped a lot. After you disassemble/clean your carb you could take a look at a procedure laid out by tashasdaddy in the following thread for burning off some possible carbon buildups:

http://forums.iboats.com/showthread.php?t=201909
 
Top