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Discussion Starter · #1 ·
I have a 1997 XLT that has been giving me fits lately. I noticed that when the throttle is closed(idle position) there is almost a 1/4" gap between the thumb piece and the block. This is allowing the little micro switch(what is this for??????) to remain open(or on) when at idle.
I am trying to chase down all possibilities on why it is so hard to start and keep running. Going to go through the carbs again today, has new plugs, fresh gas, new fuel filter.
 

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There should be 0.010 to 0/030" of play at the throttle. There are two switches in the block. If the throttle is closed and the idle switch plunger is depressed, the engine will run. If the throttle is open, the idle switch plunger opens, but the off-idle switch plunger closes. One switch has to be closed to run. When a slide hangs up or the throttle sticks, the switches detect that and kill the engine, preventing the sled from running away.

When you have too much gap at idle, the idle speed plunger is open and the off-idle speed plunger is also open, so the engine won't run. Adjust the throttle cable at the top of the carbs by loosening the cable lock nuts and turning the adjusters equally until you get the desired clearance. Some throttle cables have adjusters inline, you may want to look for one there too.

After you adjust the carbs, you should check the carbs for proper synchronization to ensure you didn't change that.
 

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Discussion Starter · #3 ·
Thanks for the quick reply Dan. I really appreciate it!!

I definately have more than .010-.030 play there. I believe the only adjustment is at the carbs.
Which way should I turn the adjusters on the carb, in or out?

Also, I will most likely have to replace the whole throttle block, the hole for the pin that holds the thumb lever on is pretty slotted out.

The idle switch plunger is the one that is visible when the throttle is opened?

I believe this is part of the problem, but not the whole problem.

Just got in from checking it out. With the throttle in it's current position, there is no spark. I then held the throttle against the sitch and have spark.
I removed the plugs, they were wet.
Cleaned/dried them and reinstall.
Set the choke and pulled it over.
It fired on the first pull and none after that.
After 3 pulls I shut the choke off.
Pulled about 10 more times and nothing. This was all with the throttle pushed against the idle switch.
Removed the plugs and they are wet again!!


I'm really getting frustrated with this thing. It ran better with old gas/dirty carbs than it does now!!
 

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There is supposed to be a slot there. That is part of the function of the throttle. That is also how you test to see if the switches are working; with the engine idling, hold back on the throttle pin as you press the lever. It can't move forward in the slot, the engine dies.

I don't recall which direction to turn the adjusters, but I think it's counter-clockwise. Turn them all equally a turn and see if the play is reduced. If the space gets bigger, go the other direction. Fix this problem first, it's likely the starting problem will go away when the throttle is adjusted properly, especially if it was running fine earlier.
 

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Discussion Starter · #5 ·
Thanks again Dan.

I'll try the adjustments in a bit.

Just got in from the garage, and smell like old gas again. After doing some reading and searching and reading more, I decided to pull the block drain plugs. Guess what???? Close to 1/2 quart of old gas was in all three combined. That might explain the wet plugs......

What causes this, other than sitting with the gas valve on? Makes me want to go out and check the other one too.

Now, has/will this cause me any issues already/down the road???
 

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Most of the time, gas in the crankcase is caused by a leaking needle/seat in one or more carbs. The leak can be caused by a groove in the needle from wear, or dirt/varnish that prevents a good seal. Another cause is a float that is not adjusted correctly, or one that has a hole in it and is sinking. Another way raw gas can get in the crank is through the fuel pump diaphram. If the diaphram ruptures, gas goes right from the tank to the crankcase through the fuel pump and impulse line.

Shutting the gas off when the sled is not being used will eliminate the gas in the crankcase problem. Trailering the sled with the gas on makes the problem worse. It can get bad enough that when you crank the engine over to start, enough gas goes into the cylinder that it can hydro-lock the engine, making it impossible to turn over. Removing the spark plugs and pulling the rope results in a LOT of gas coming out of the spark plug holes. This can be VERY dangerous, especially in an enclosed trailer or in a garage.

Raw gas in the crankcase can clean residual oil off of the bearings and crank, resulting in loss of protection from rust. It's definitely not good on the engine.
 

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Discussion Starter · #7 ·
Thanks for the info Dan.

Had it out for a little ride yesterday and it runs OK, just not like it should. Still doggy on the low end, sems to run out OK on the top end. Still don't think it is 100% there either though. Good news is, no more fuel in the crank case, just a few drops after about 10 miles of riding.

I believe it is in the carbs, going to remove and disassemble again. Also going to replace all 3 needle and seats just because. This sled sat for 3+ years and didn't move, so I expect a few issues. But, my Ultra sat for the same amount of time and it goes just fine.
 
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