88 Snoscott Fueling Issues

lilnotts

New member
Joined
Jan 25, 2011
Messages
8
Age
37
Location
Sarnia, ON
I'm working on a 88 Snoscoot for a friend at work. It would run at all when I got it, so I cleaned out the carb as most of the jets were plugged up as it sat with gas in it. I also found the the stock fuel pump would no longer pump. I had a spare old Mikuni fuel pump from my TNT so I tried that and it would start up and run but not well as it would sometimes run fine and go to full throttle and then bog down. I had also found that this spare old pump was leaking fuel out of a vent so I figured that I must need a rebuild.
I ordered a rebuilt kit for my spare to have on hand and a new universal single in single out fuel pump for the scoot. Now with either pump it will not run. If I put gas in the cylinder it will run. With the hose off the carb it will pump fuel through the hose. I went through the carb again to make sure I did not miss anything. I even rigged up a gravity feed system to feed some fuel to the carb and tested the float valve and it works fine. Which makes sense as the bowl is always full whenever I take the carb off as I have done it a few times looking for something that might not be working properly. It almost seems like its not sucking the fuel through the carb into the cylinder. I'm now at a loss of what is wrong. Any ideas?
 

Update: I tried it again today with an empty fuel bowl, opened the petcock, turned the key and it started up with the choke. At first it did not want to idle well then the rpm started to climb to rough 2/3 throttle where it ran at that level for a second or two before it died. Would that have been the TORS that shut it down as I was not actually touching the throttle? Also, after it died it would not start back up.
 
SnoScoot

lilnotts,
I have two Scoots and what you are describing is not uncommon. I will be cleaning both of the carbs again tonight. One of the scoots I restored was sitting outside for about 10 years before I got a hold of it. I bought all new jets and cleaned the carb about 10 times. I could never get it to run great. It was always hard to start and would often die for no reason. I messed with the fuel pump, the fuel filter, choke adjustment, pulled the gas tank, on and on. Out of frustration, and going against reason, I bought a new carb. I bolted it on and presto it ran flawlessly. Even after sitting for weeks or months, it starts on the first kick. It runs like a new machine.

I just bought my 2nd scoot at the end of last season. It runs well, however, it takes a long time to get it started after it has been sitting for more than a day. I sometimes have to kick it 50 times (literally-I counted) - as if it is fuel starved, however I'm sure the bowl will be full when I pull it. Once it starts, it idles and runs great. I am sure it is carb related. This is why I'll be pulling the carb tonight and soaking everything AGAIN. The strange thing is, it usually fires on the first kick but won't stay running and then I need to kick it over a million times to get it to start again.

I turned my buddy on to these machines and he is now somewhat obsessed. He has (5) of them. He has had every carb off multiple times to clean them. I believe he now has them all running well with the original carbs.

All this being said, you should be able to clean it, but it may take several attempts. You need to pull all the jets, if you haven't already. My buddy swears by Mercury Power Tune carb cleaner. It is thicker than the Gumout spray stuff and it seems to coat everything and allow you to use a toothbrush to clean it. You should also make sure there is no crap in the tank. Inside the tank there is the fuel filter on the end of the fuel pick-up. Mine was all nasty and I had sediment in the tank as well. You don't want to be sucking dirt right back in to the carb you just cleaned. Also, make sure your foam air filter is not deteriorated and falling apart (mine was). The little particles can easily get sucked in the carb and clog it up right after you cleaned it all out.

Let me know your progress and I'll let you know how I make out tonight. I may have some other ideas as well.
 
Make sure that the rubber plug that goes into the hole that the pilot jet screws into is good and tight. I have had those shrink up and I'e seen scoots that have had them missing.You can plug them up with any small piece of rubber etc. just to test it... the plug is still available from Yamaha. Try that... I'e had two of them get loose and not seal tight and it does all kinds of wierd s*%t.
 
try gunk carb and parts cleaner it comes i a white gallon can that look like a paint can , take the carb apart (all rubber out) then soak it in the can @ hr. it says 20 min. but do it for an hr. , take it out wash it off good with water then blow it off good with an air hose . when your done you will think you got a new carb the hell with all that scrubbing . this stuff is a very mild acid and will clean all the little ports (don't soak the float's not good lol.)i have cleaned @ 15 carbs with 1 can and it is still going and for @ 25 bucks cant beat it.
 
carb cleaner

cschibik,
That carb cleaner in a latgr can sounds like the way to go. Where did you buy find it? I went to Murray's/O'Reilly's and also AutoZone - NO LUCK
 
I had 3 scoots in the past. Buddy of mine just got one this year. We went through the same issues as you. In the end, the unfortunate solution was a new carb. Fought and fought, but just couldn't resolve the problems. Dropped a $300 carb in 3 of the 4 scoots and problem was solved.
 
Fleabags said:
cschibik,
That carb cleaner in a latgr can sounds like the way to go. Where did you buy find it? I went to Murray's/O'Reilly's and also AutoZone - NO LUCK
try napa if you have them in your area. napa's are in a blue can .advance auto is where i got mine.
 
I"ve cleaned the carb i'm not even sure how many times now. On the last time I ended up ripping the little rubber plug so i've order a new one of those as well as some of the jets as the are partially stripped. I"m going to try to look for this carb cleaner you guys are talking about and try that. My air filter was also in poor shape so I ordered one of those as well. I've pulled the in tank filter and put an in line one in so it should be getting clean fuel. Currently it will fire up for about 3-5 seconds every time if I let it set for a day but runs no longer than that. If I try to start it after the intial start for the day it wont fire. Spray gas in the carb with a spray bottle it runs like a dream.
 
Update: I found that carb cleaner and soaked the carb for a few days. Installed a new air filter, main jet and nozzle as well as a new black plug. Now it runs like a dream.
 
glad to see that it worked for you . just keep the can closed when not in use and you will have it for years.
 
snoscoot

sxr1000 said:
It could be a bad fuel pump or bad rings that would not give the pump enough pulse to make it work.
A guy from snoscoot .com told me that there is a part of the carb that is not cleanable or removeable,and if it clogs then you need a new carb.I have heard of ultrasonic cleaning not working and several other cleanings that were unsuccessful,so sometimes a new carb is the only answer I was told
 
carb cleaning

Bought 89 scoot that has sit for 4 years.Fixed kicker.Cleaned carb (jets would not loosen)Got rid of mouse nests ,replaced in tank fuel filter and gas lines and added additional filter right before carb .Started up and ran for a short ride and thought carb was ok .Tore sled apart and replaced track ,rings air filter ,other small stuff .Re-assembled noticed enricher was not moving .Soaked enricher with carb cleaner and it finally pulled out with cable .Replace top o ring:SOLUTION Yamaha carb dip. Boil 4 cups water in coffee can add 2 cups Yamaha carb dip and carb keeping the wires and switch out of the solution ,When you see the cleaner start to flow and clean set the burner to low and leave carb in for 10 minutes.Now the jets came loose throw everything back in the almost boiling dip for another 10 minutes.Rinse with water and spray with compressed air and then can carb cleaner to remove and residual water and gunk.Inspect all 4 jets and openings.Reinstalled .started on enricher and continue to run with enricher off (scoots will run on enricher circuit only and die when enricher is shut off)Hot Yammie dip is the carb cleaning solution instead of buying a new carb$$
 


Back
Top