# Need help on what is wrong with my sled!!!!!!



## deerhunter#1

i have been just tooling around my house on the snowmobile and it has been running fine but now it will go for about ten minutes then starting bogging out and not revving when i hit the gas. it will still start fine so i dont think it is the spark plug. 
thanks 
Jake Grapentien


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## SalmonBum

deerhunter#1 said:


> i have been just tooling around my house on the snowmobile and it has been running fine but now it will go for about ten minutes then starting bogging out and not revving when i hit the gas. it will still start fine so i dont think it is the spark plug.
> thanks
> Jake Grapentien


What sled?


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## deerhunter#1

its a 1983 yamaha srv 540


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## SalmonBum

Hmmm..... Thats a little old for me to troubleshoot. Do a compression test, inspect the clutches and check yoru carb boots for cracks. Look Visualy, but then start the sled and spray carb cleaner near the boots. If the motor sound changes, then you have bad boots.


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## tapsoy68

Could be the clutch or bad gas.


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## Burksee

Several things could cause this, Could be a weak fuel pump? Check the vaccume line between the engine and the fuel pump, I've had them leak/colapse and cause fuel pump to operate at less then desired volume/psi.


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## thunder river outfitters

you might wanna clean the bowls on under the carb....thats something you should do every other year. it will sit and idol just fine until you start to ride.when you take off, particals start to brake off from not being cleaned and stop your fuel flow.....thats my geuss.
under your carbs are tiny small screws.,,, just loosen them up and drain them little by little ....you will have to do this about 8-10 times. you should be good to go.


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## deerhunter#1

yea i thought it might be something with the carb but the problem is to take out the carb and clean it you have to take off the seat and gas tank. if i can get to it with some carb cleaner it would do the job.


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## Raymond S.

My little bro had an old SRV 440 and I'm pretty sure you don't have to take the seat off, in fact someone should be shot if that's the case. You should probably just need to take the airbox out and get to the carbs. I would try running a little seafoam through there first. Maybe you would get lucky and that'll do the trick. If not, nothing hurt. May get you back to tooling around the field.


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## Busterboy

Burksee said:


> Several things could cause this, Could be a weak fuel pump? Check the vaccume line between the engine and the fuel pump, I've had them leak/colapse and cause fuel pump to operate at less then desired volume/psi.


I second the weak fuel pump, have seen that on that era of Yamaha's myself. A quick test is to disconnect the fuel line between the fuel pump and carb and then using another line, blow back toward the pump, against normal flow. If you can blow a decent amount of air through the pump then repair it. The 'check valves' in the fuel pump get weak over time and will still pump fuel but cannot keep up at the greater flow needed for the higher speeds. 

Busterboy


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## MEL

And dont rule out a bad plug/bad wire. I had an old Yami that started fine and ran like crap when warm.....changed the plug and it ran like a champ.


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## CHASINEYES

Just had a similar problem with an old jag. It would run good for a while then acted like it was running out of gas. What I found was, oil in the pulsator line,( line from crankcase to fuel pump) the fuel pump was working, but not at full capacity. I also dismounted the fuel pump and oil dripped out from that. This line should be free from any liquids. Runs great now.

I also checked the line inside the tank , as I have seen them get weak and collapse when the pump is trying to suck fuel. Look for a fuel line that could be pinched, when heat gets to a pinched line it can collapse(softens with heat) and cause the problem your experiencing. Also you may have a little water in your gas, if so after running a while ice crystals will build up in your fuel filter, the longer you run it the worse it gets until no fuel makes it through the filter.( especially with these temps) If you think you may have water in your gas, get the sled in a heated area so the ice will thaw and add dry gas. Dry gas will keep the water from freezing again, but you have to get it thawed first. With the temps we are having I bet water in your gas is the problem. These are just some things I have experienced with my own, friends and family members sleds. Hope it helps.


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## YZman

You can get the carb off fairly easy as I had to do it years ago on a friends SRV540, on the side of a trail with only the tool kit. But the rubber boots to the airbox and reed valves were probably alot softer then.

IF the engine runs good for the first ten minutes, then starts to bog down as MEL said you can try changing plugs. I've seen hairline cracks in the porcelain short the spark out as the engine warms up. That engine uses one coil with (2) permanent wires, firing both plugs simultaneously. One pulser w/one source coil. Also for a quick check you can pop the gas cap to make sure the vent isn't plugged forming a vacuum.

As was also stated check the pulse hose from the crankcase to the fuel pump.

But... as somebody else made a comment about the clutch. Are you sure the clutch is opening all the way back up. The clutches on those machines have (2) brass bushings that are supposed to pivot in the aluminum housings. If they are not lubricated every so often they tend to bind and produce a bogging affect. If you undo the (6) 10mm head bolts evenly (big spring underneath), you can get to the outer one. You should be able to take this bushing and twist it 90 degrees; line up with two casting slots and remove it. I'll lay odds that you won't be able to do that! The inner one requires that you remove the clutch from the engine shaft (clutch puller required; just a special bolt the screws in ~$20.00). Then the fun part of heating the bejesus out of it to unthread the sheave from the shaft. If you wish to take the cheesy cowards way out, alot of times you can use a little heat and WD40 on this inner one to get it freed up by rocking the inner sheave while working some WD40 in the casting slots; doing this without removing the clutch from the engine, but having the outer cover off as previously stated. 

When removing outer cover watch for falling pin, washers and rollers, as the (3) pins for the weights are just slide in and held in place by that outer cover.

YZman.


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## Itry

I'd try the dry gas, but I bet it's the fuel pump! I had a polaris that did the same thing. When it was cold it ran fine, But after it warmed the diaphram inside the fuel pump expanded and it ran like crap. At the time you could get a rebuild kit for them for 5-6$


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## tracker14

for the few bucks try new plugs. My sled starts fine on a fouled plug but won't go worth a crap. If your just tooling around it might have fouled.


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## chainbreaker

Clean your carb out,as in remove the carb and remove the jets and blow them carefully out,also use carb cleaner on the job. I would spray the carb with carb cleaner before removing the carb and blowing all the crap off. Do not get the carb cleaner in your eyes!!! :yikes::yikes:


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## big show

try running seafoam through it.


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## tracker14

big show said:


> try running seafoam through it.


 with the choke on reving it up will help it too. it will smoke alot from the seafoam.


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## Halffasthog

When it starts to die out, see if it will run a little better/ longer with the choke. If it does, you definitely have a fuel delivery problem. Pump, vent, hoses, needle/seat, main jet. That's the order I would attack.


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## Ralph Smith

Not to hi-jack the thread, but I have the same problem with a 1971 Evinrude Skeeter, any ideas?


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## Burksee

Ralph Smith said:


> Not to hi-jack the thread, but I have the same problem with a 1971 Evinrude Skeeter, any ideas?


Yeah, read the previous 19 posts! :lol:

That old Skeeter should have a Tillitson/Walboro pumper carb, Probably needs new diaphrams. Check your fuel lines for cracks/leaks, anything that can cause air to sucked into the line. It might be a good time to replace the fuel lines. Intank fuel filter and check the vent on the cap, I've seen them get plugged and its like a boat tank when you dont open the vent, not that I've ever done that more than once! :yikes: :lol:

Speaking of boat motors, I know some older sleds use a bulb primer inline just like a boat, if you've got one of those check it to!


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## Ralph Smith

Burksee said:


> Yeah, read the previous 19 posts! :lol:
> 
> That old Skeeter should have a Tillitson/Walboro pumper carb, Probably needs new diaphrams. Check your fuel lines for cracks/leaks, anything that can cause air to sucked into the line. It might be a good time to replace the fuel lines. Intank fuel filter and check the vent on the cap, I've seen them get plugged and its like a boat tank when you dont open the vent, not that I've ever done that more than once! :yikes: :lol:
> 
> Speaking of boat motors, I know some older sleds use a bulb primer inline just like a boat, if you've got one of those check it to!


Read all the others, figured by now the original poster got his fixed(I hope). Fuel lines are good, left cap loose, can't find any air problems. There is a fuel filter on side of fuel pump that is clean, didn't know there was one inside tank too, will have to take tank off. I can run it fine using primer by bypassing carb, so somewhere gas is being restricted. Thanks for the help, may have to try and find an old fuel pump, don't think there's any diaphrams on carb.


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## AL D.

Had the same problem with my 83 SRV 540 and it was caused by a broken expansion chamber(no back pressure) Took the pipe off the sled and welded the 1inch by 2 inch piece that broke off back on and ran like new again. Try running the sled and feel for leaks on or around the pipe. Al :chillin:


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## Ralph Smith

AL D. said:


> Had the same problem with my 83 SRV 540 and it was caused by a broken expansion chamber(no back pressure) Took the pipe off the sled and welded the 1inch by 2 inch piece that broke off back on and ran like new again. Try running the sled and feel for leaks on or around the pipe. Al :chillin:


Thanks, but this beast don't have any pipes.:lol: They have an opposed twin engine with exhaust blowing straight out bottom twards front between skis. Only thing is a plate over hole, sort of like a suppression type baffle to quiet it a little. They are a little loud.


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## AL D.

Ralph Smith said:


> Thanks, but this beast don't have any pipes.:lol: They have an opposed twin engine with exhaust blowing straight out bottom twards front between skis. Only thing is a plate over hole, sort of like a suppression type baffle to quiet it a little. They are a little loud.


Check for leaks............


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## spazbrevik

You need to check the condition of the gas tank. If you have a metal gas tank there could be a lot of corrosion in it. There may also be a filter on the fuel pick up line. If the tank is in bad shape get some muratic acid and put this in an empty tank with some nuts and bolts. Agitate the contents until the tank looks good and then start form there. I learned the hard way rebuilt carb before cleaning tank good enough, makes for a lot of work to redo all of the work you just did.


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## Burksee

I wish people that ask for help would follow up and reply on what they found..........This tool hasnt been back here since 1/27, waste of time posting to this thread.


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## Ralph Smith

Burksee said:


> I wish people that ask for help would follow up and reply on what they found..........This tool hasnt been back here since 1/27, waste of time posting to this thread.


Sorry, left last Sat. to go to Willard,Ohio just to keep a job, no computer, and sleeping on a cot in an upstairs apt. rented within day to have a place to stay. No furniture, or anything but fridge and stove. So I just now got a chance to get on here. I won't be looking at it till probobly summer time now, since my time is limited to family when I get home. Hope this give you the reason why I haven't had a chance to reply. If I don't reply to a post on here, there will be a good reason. Hopefully in future at some point I'll have a computer in Ohio and can post on some lake Erie fishing. Didn't mean to leave you hanging, but my life comes before the internet.:rant:

Thanks to all for the advise given, I will post what the problem was when i find out myself.


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## Burksee

Ralph Smith said:


> Sorry, left last Sat. to go to Willard,Ohio just to keep a job, no computer, and sleeping on a cot in an upstairs apt. rented within day to have a place to stay. No furniture, or anything but fridge and stove. So I just now got a chance to get on here. I won't be looking at it till probobly summer time now, since my time is limited to family when I get home. Hope this give you the reason why I haven't had a chance to reply. If I don't reply to a post on here, there will be a good reason. Hopefully in future at some point I'll have a computer in Ohio and can post on some lake Erie fishing. Didn't mean to leave you hanging, but my life comes before the internet.:rant:
> 
> Thanks to all for the advise given, I will post what the problem was when i find out myself.


Ralph, I think you miss read my post. It was not at all directed at you. I apoligize if you took it that way. It was in regards to Deerhunter#1, the guy that started this thread. You HJ'd his thread and got some advise as well, I wish I had a better idea of what carb was on that old Skeeter of yours. Take care, hope to see at the AS river party!


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## Ralph Smith

Burksee said:


> Ralph, I think you miss read my post. It was not at all directed at you. I apoligize if you took it that way. It was in regards to Deerhunter#1, the guy that started this thread. You HJ'd his thread and got some advise as well, I wish I had a better idea of what carb was on that old Skeeter of yours. Take care, hope to see at the AS river party!


No problem, thought about that after I posted. No harm done. This Ohio stuff is gonna drive me nuts, I can see it. On a good note, a coupe guys I work with, fish Erie alot in port clinton area and over twards Maumee, so I'm looking forward to learning some areas I've never fished.  They say there is plenty of perch down there also, so lookig forward to that.


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