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Discussion Starter #1
First, thank you for taking the time to read my question and taking even more time to respond. I often work on lawnmowers, weedeaters, blowers, etc but not too often on four wheelers. A neighbor brought this 1995 Polaris Xplorer 400 4X4 over that had been sitting for a few years. the first thing I did was dismantle and completely clean the carb which had oil in it when i opened it up. I soaked it and cleaned all passages and set float level. I then replaced the fuel lines and fuel filter as well as the main fuel tube that had collapsed in the tank. New spark plug as well.

Well, I can use the choke to get it to crank and it runs very strong at medium to high RPM's but well die at idle. I opened the carburetor back up and cleaned it once again and got the same result. I then ordered a carb kit and replaced the jets, air screw, needle, and needle seat. I backed the air screw out 1 1/2 turns as indicated in the manual. It ran a little better and improved a little more as I turned the air screw in but it still will not idle.

I really have no idea where to go from here because I performed three cleanings on the carburetor and finally replaced the jets, needle and seat.

Any guidance will be much appreciated.
 

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You may simply just have to turn up the idle or adjust the cable for the ETC to keep from making contact in the throttle housing and killing it at idle. Or you either still have a partially plugged pilot passage or if it's a 2 stroke it may have a leaking crank seal or cracked carb intake boot.
 

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Discussion Starter #3
electric switch on the thumb throttle

I've been told that there is an electronic switch on the throttle assembly that senses if the throttle cable is broken and will shut it down at idle. Is this the case and how can I test it?
 

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Forgive my ignorance

You may simply just have to turn up the idle or adjust the cable for the ETC to keep from making contact in the throttle housing and killing it at idle. Or you either still have a partially plugged pilot passage or if it's a 2 stroke it may have a leaking crank seal or cracked carb intake boot.
What is the ETC? I have adjusted the idle to the point it was too high but that was the only way it would stay running. I'll sure check the crank seal and carb intake boot in the morning. Thank you so much for responding to me.
 

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Discussion Starter #5
Low compression

I only have about 90 lbs in compression test. I read that if it's below 100 it needs a rebuild. Can anyone tell me what a normal compression test should read?
 

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The etc is the throttle safety switch. It's inside the thumb lever housing. When you do compression test, cold, full throttle, 3 pulls in the recoil. At 90 you'd have a really hard time starting it and isn't would be poor like it is.
 

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Discussion Starter #7
99-105 lbs

I rechecked compression and with three pulls I'm getting 99-105 lbs between two tests. If I try to crank on choke it sputters for half a second but won't start. Shoot starting fluid in it and give it some gas and it starts and runs great above idle. I rechecked carb and it's clean and installed new jets and float height is correct. ETC is working correctly. Am I correct in assuming low compression is the cause of hard start and no idle?
 

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Discussion Starter #9
I have to accelerate it some to keep it running but there was no RPM change when spraying starter fluid in either spot.
 

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Then your crank seals are good. Sounds like compression is just on the edge of keeping it running. Time to rering at a minimum. Maybe bore and new piston and rings. You will know after you open it up and measure things out.
 

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1995 Xplorer Idle Problem- I had the same issues

Hi, I have a 95 Xplorer 4x4 2 cycle... same problems. My machine would start fine but would not idle at all. It would run fine as long as I was giving it gas... and if I would run it down the road for about 5 or 10 minutes... sometimes it would idle for a while but ultimately would die.

I tried everything... I rebuilt the card twice... I replaced the throttle assembly and the rubber boot between the carb and engine also replacing the reed valve... I had it to the dealer twice and an independent guy once... to no avail.

Anyway, I finally decided to just rebuild the engine. When I broke down the engine and cracked the crank case, I found that the seals had been leaking for quite some time. There was water and rust in the main crank case and the bearings were rusted. There was also rust and dirt (oily dirt) in both the water pump/counterbalancer compartment. Found the same in the electric rotar/stater compartment.

The crankshaft was out of alignment and I had a knowledge friend true up the shaft (the imbalance of the shaft wore the bearings and seals of the crankcase).

I replaced all the bearing and seals in the engine. Rebuilt the carb (again) although I also replaced the float arms and float arm pin (I noticed the gas would stop flowing to the carb when watching the clear filter).

Finally, I finally figured out the vent lines from the carb and crankcase and ran them up high into the gas tank area.

Basically, I believe the seals were worn down from the crank alignment and this did not maintain the vacuum in the crankcase. From what I've read, 2 cycle engines need a good seal in the crank case where the gas and oil mix and then are fed into the cylinder.

The old quad runs GREAT now! I've had it out for 3 hours in the most recent snow storm and plowed my 1/4 mile driveway the next day.

It sounds like you may have same problems. Rebuilding is not that hard. I'm an amature and I could do it with the help of a step by step manual. I took my time over several months (and having to buy special tools). But, it has all worked out in the end.

Good luck!!!
 
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