91 SJ issues

M

moetank

Sorry for the long post but here goes. Ok this has been plaguing me for about 2 weeks now, I picked up a stock 91sj, ran fine took it for a test run and have put about an hour on it since I got it, as it is just starting to get nice out. I was ridding it memorial weekend took a rest, restarted it, hit the throttle and it died. Could get it to run with gas in the carb but not sucking fuel on its own. Changed fuel filter with a fram inline as I couldnt find the stock one anywhere in town. Ran great for a min then same thing that filter was clogged up. Drained the tank cleaned out, and rebuilt the carb the screen inside the carb was completely full and clogged I figured that was my issue. Now all back together and it will idle fine but if you give any throttle it dies. If you hold the choke down it will rev full throttle fine but smoke like hell . Tried turning out the high end to no avail.
Im thinking maybe the inline fram filters just dont have enough flow? I ordered a couple stock ones and am waiting on them. Just not sure what else it could be Ideas? Also what is good place to be on the stock hi low mixture both were set at 2 turns out when I started. Oh and 1 last thing there is no FA on it could this be an issue?

Thanks For any input
 
M

moetank

Update-

I removed the fuel filter from the system and it fired right up, and would rev up well, I put it into the water and same problem wont rev above idle under load, turned the high end out to 2.5 turns and the low end at 2 turns and it will rev wide open but has a bad mid section hesitation. So my question now is am i fighting something else and just compensating for it or is it alright to be turned that far out on the high end and i just need to fine tune to get my mid range. Also still no FA not sure if that has an affect of it or not.
Thanks again for any input I'm sure these our nube questions I'm just somewhat at a loss.
 
T

TnT

I just wan na fly
Location
Knoxville, TN
By chance did you check the tiny little filter that is inside the carb? My SJ carb fuel filter was clogged and it pulled that crap with me all day long. As soon as i openned the carb i noticed is the little filter and it had quite a bit of junk in it. cleaned it out and BOOM ski runs great
 
M

moetank

The filter in the carb was changed as it was completely clogged I ordered a stock FA I also have the adapter but not sure on a K&N part number for it. How do I go about checking the tank vent should air flow both ways or only out of the tank? I have the new Fuel filter on and it will run just have to have the high jet turned out 2.5 turns and there is still a mid range bog. I will try to borrow or buy a compression gauge.

Thanks again for the input
 
T

TnT

I just wan na fly
Location
Knoxville, TN
The tank should only flow air into the tank. If you are able to get air to go past the one way valve then your fuel system can not create any pressure and your ski will die at around a half a tank.
 
R

ridethelip

Guest
Anytime you use the choke and the engine seems to run better you have just learned that you have a lean condition (not enough fuel).There are 2 allen screws that allow access to the low speed fuel passage.One is underneath carb where carb mounts to intake manifold and the other is on the needle and seat / jet side.Completely remove mixture screws ,allen screws,jets and use contact cleaner through passages and compressed air.Sometimes these are over looked.It would be a good idea to verify what your pop off pressure is.Extremely high needle and seat pop off (50 psi) will cause a very poor off the bottom performance and flat or weak mid range requiring you to milk the throttle to even ride the ski.Stock exhaust,carb(with stock jetting) and flame arrestor should have a pop off of at or near 30 psi. Good luck!
 
You must log in or register to reply here.
Top Bottom