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Discussion Starter #1
Hello all, seasoned polaris owner first time here. I have a problem.

First of all I'm glad to have joined I've always turned to the forum as a guest for quick info.

Secondly, my problem is as follows.

I own a 1999 Sportsman 500 4x4 (5th sportsman) to explain the quad in a quick overview... Well everything is broken, well not everything. Main kill switch barely makes contact anymore and the starter aspect of it has been long gone headlights as well. Starter is wired to a push button and pod light was wired also. Fans are hardwired to the key.
I purchased this quad years ago and to be honest i can't recall a day she has had off, we own a farm and is used for feeding horses and maintaining the land. Every day multiple hours a day. She eats up a battery every 6 months.

Since day 1 its always made top end noise, rattle almost. But thousands of hours of use later it never posed a problem.

Last week i went down to the barn to run around and feed, wouldnt crank. Busted the charger out to jump it (battery is due from the cold) crank and crank amd crank, no start. Go to pull plug out and the wire breaks, stiffer than crap. So order and new coil boot and wire
Great spark, no fuel. Ordered new carb since its needed work for 2 years now from the bowl leaking so just picked a new one up. Same thing.

Plenty of spark and plenty of fuel in the carb but not getting past that, will not make it to the engine.

Ive wasted a lot of time on it at this point and cant figure it out. Any and all info is greatly appreciated

Thanks guys!
 

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You are gonna have to pull the carb and fix the needle/seat or plugged jets. Needle/seat meter fuel into the carb and if the float is stuck, it would not allow anything inside the carb. If jets are plugged fuel inside the carb fuel can't get to where it needs to go.

Did you get a cheap Chinese knock off carb or an expensive OEM piece? Too often here we see complaints about the cheap ones not working with the machine and requiring extra effort to make them go. In my opinion you are much further ahead to rebuild the original instead of replacing it. A rebuild kit for the OEM carb is about $40. Probably just the needle/seat leaking on it.
 

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Discussion Starter #3
But the old carb acts the same as the new carb
 

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Then you have the same issue with both carbs. One or the other needs to be fixed. I would return the "new" one and spend $40 on a rebuild kit. With everything you have been able to do with the machine up to this point, I am sure you can clean the carb and install a rebuild kit. Your needle/Seat is leaking most likely. Worst case would be the original carb has a split in the overflow tube.....But Latebird here on the forum can replace that for you.
 

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Discussion Starter #5
When I spray starting fluid in the head through the spark plug hole it blows the fluid back through the carb, almost as if it's out of time and not building pressure on the correct stroke. Like the intake valves aren't opening at the right time.
 

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Discussion Starter #7
Check compression/ valves
Definitely has compression or from my knowledge of autos (trade mechanic) if no compression was present there would be no blowback from pressure build up internally, which leads me to believe there is something wrong with the intake valves or timing to which it is not allowing air into the motor on the down stroke. On my particular model it is very tight clearance around the top of the engine and unfortunately my compression tester is old school with a rubber boot and just simply cannot get into the small space, although I know I could easily find the internal problem by removing the access panel to check timing and valve cover to check rockers and valve clearances.
I really didn't want to get my big hands in there with my broken finger to un screw little 8mm bolts if I didn't need to, so was inquiring about a possible external issue if someone maybe had experienced this before.

My uncle who is a retired small engine guy told me a friend of his has an 03 500 that spit out the same issues and it had jumped a tooth on the chain. My next question would be what kind of damage am I looking at if it did in fact jump time? Head rebuild? Is it an interference engine? Again I am NOT a small engine guy so I can only apply my knowledge to my particular situation but how the small engine works is not my Forte. I've always had polaris and always will but I have been fortunate not to be challenged by anything internal yet to this date.
 

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LOL, that's what I'm talking about. Sounds like you have valves that need attention. You'll have to get the tank off to get in there to figure out what's wrong/inspect/adjust valves or to pull the head if needed. I guess it could happen if chain, sprockets, tensioner and stuff is completely worn out but it is NOT common for a 500 Fuji engine to jump time. I HAVE however, seen a bunch of them that needed valves adjusted/refurbished though.
 

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Discussion Starter #9
LOL, that's what I'm talking about. Sounds like you have valves that need attention. You'll have to get the tank off to get in there to figure out what's wrong/inspect/adjust valves or to pull the head if needed. I guess it could happen if chain, sprockets, tensioner and stuff is completely worn out but it is NOT common for a 500 Fuji engine to jump time. I HAVE however, seen a bunch of them that needed valves adjusted/refurbished though.
What damage would it have caused to the short block? What should I be expecting? Bear with me, lol
 

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There's no way to know for sure but I doubt you have any "damage". We're all just guessing till you get in there and see what the problem actually is check timing, valve clearance etc.
 

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Discussion Starter #11
Good deal, I will post update this weekend
 

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Discussion Starter #12
Ok, got into the access panel. Jumped 8 or 9 teeth, tensioner is shot. Best solution? Top end kit? Rebuild while shebang? If rebuild where to go for cost efficient kit?
 

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Here's a compete top end kit with cylinder, tensioner and all for $116. I can't vouch for the quality or durability but it is cheap. The only other things you'd probably need is a timing chain and sprocket. I'd take a real close look at the cam though while you're doing it.
 

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Discussion Starter #14
Here's a compete top end kit with cylinder, tensioner and all for $116. I can't vouch for the quality or durability but it is cheap. The only other things you'd probably need is a timing chain and sprocket. I'd take a real close look at the cam though while you're doing it.
Ok i got the head off, other than some carbon on the valves they look ok, piston has a couple of small marks but i dont think it will cause any harm. The tensioner did not seem tight when I looked at it before head removal. I'm wondering how to tighten the tensioner to put more pressure on the chain. If it will tighten I could put it back together with a new head gasket, re-time it and probably be ok. What do you think?
 

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Ok i got the head off, other than some carbon on the valves they look ok, piston has a couple of small marks but i dont think it will cause any harm. The tensioner did not seem tight when I looked at it before head removal. I'm wondering how to tighten the tensioner to put more pressure on the chain. If it will tighten I could put it back together with a new head gasket, re-time it and probably be ok. What do you think?
136865
 

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You need to remove the valves and inspect the guides for damage - new valves, head cleaning, new cam chain, possible new tensioner - because of it's age, I would recommend boring to an oversize and new piston and rings (top end rebuild) or cut the losses and part it out, sell it complete, trade it in - choices are fix it, get a different one or do without one.
 

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Discussion Starter #19
136871


This is my camshaft
 
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