A buddy of mine has a 1997 sportsman 500 that he bought last year with roughly 1200 miles on it. It was in pretty nice shape with low miles and the previous owner had just had it serviced with a new water pump installed. Ran really good all last summer and most of this summer until a few weeks ago. It just one day decided to not want to start right away. It would crank and crank but would take forever to fire. Once started, it ran fine. Choking or playing with the throttle wouldn't help how it started, it still would take a few attempts of continous cranking to get the machine to fire. I checked the plug for him and it was fine so I chalked it up to a carb issue. This guy is pretty good about driving his four wheeler with the fuel switch on reserve and would run it dry. I figured it was just some trash in the carb and suggested he run some sea foam through it If he wasn't up for a carb rebuild since I don't have time to do it. He took my advice and was all happy because it started to start better, but then went back to its old ways of not starting again. Just this weekend, he now developed an oil leak. It is in a strange spot I have never seen. It appears to be pushing oil out of the recoil. Not around the case, but actually up by where the recoil rope goes in. I am kinda tying these two issues together somehow because I think the oil leak is somehow related to the hard starting. A little history on this machine. Last fall before he put it away, he took it for a long trail ride of about 100 miles. On that trip, they drove in a lot of water and mud along with real dusty conditions. He got stuck in a good spot of mud which required him getting pulled out. Once they where done with the ride, they brought the atv's home for the winter and stored them. So the mud and dirt stayed there all winter. Spring came and out came the four wheeler but never got a thourough cleaning. He did have an issue of pumping coolant out of his overflow tank so I told him to do a deep clean of the radiator to make sure it wasn't plugged. Im not sure how long he rode this with the coolant issue so I don't know if he cooked the motor and the starting and oil loss are symptoms of this.

Naturally, he is constantly asking me what is wrong with his machine but I don't have time to really jump at it because I have four vehicles at home and two teenage daughters so my time lately has been replacing head gaskets on a 3.8 ford, tires and brakes on a neon and lastly to finish the balljoints and wheelbearings on my Chevy trailblazer(ain't teenagers grand!). So when I do get caught up and look at his sportsman, what should I look for? In kinda leaning towards a blown head gasket but it does seem to run fine once started.

I am a firm believer that soap and water, grease, oil and filters are a while lot cheaper than a new motor so that's why I use a lot of that and mine run like a top, lol.

Thanks,
Mike

 

Start by doing a full service front to rear. People find a lot of neglected problems just in doing that. As far as oil in the recoil,could be coming from two places. The big o-ring around the stator plate or the seal.#4,#8.Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse If there is enough oil in the housing it could coat the pick up coil and make it hard to crank.Plus after cleaning this area seal around the recoil housing with a good rtv sealant and seal the rope handle to the housing to help keep out water and dirt.

 

This happened to me when my 500 was hard to start.

The pull rope handle is the only thing that keeps dirty water from going down the recoil's rope hole and inside the recoil case.

Inside that recoils is parts that do not like to take swims such as the Pulse coil ,Stator ,fly wheel and Bendix drive.
In my case the pulse coil's magnetic contact face that meets the fly wheel was filthy , once I cleaned it up the ATV started great again.
Now I silicone the pull rope handle into it's position for a water tight seal, it's been good for years now.

 

Thanks guys,

Looks like I got roped into fixing this one for my buddy. I'll star with a good washing to get the dirt out of the hard to reach places. I showed him earlier this summer where all the millions of grease fittings are on his sportsman and to make sure he greased it regularly if he road in a lot of mud and dust. As far as the seal and o-ring goes, it looks pretty straight forward. Take the running board off to get to the recoil and take that off to get to the flywheel. Pull the flywheel and pull the stator. What do you recommend to clean the insides of the recoil and stator? Would brake/parts cleaner harm anything?

Thanks,
Mike

 

Electrical contact spray cleaner is better,less caustic on plastic coated parts than brake cleaner. If leak is from the stator plate,mark it before you take it off,lightly oil the new o-ring when you install it and the plate may need to be twisted a tad when seating it,the align your marks.If a seal is leaking,just pop the old one out and tap the new one in flush.

 

I got time to work on the sportsman this weekend and the seal was definitely leaking. When I pulled the recoil housing off, a bunch of oil came out. I replaced both the seal and the o-ring and cleaned everything up good. Put it back together and topped the oil off but it still doesn't start very well. It has excellent spark and is getting fuel to the carb but you have to crank forever with the throttle wide open before it will attempt to start. It sprays fuel back out of the carb when cranking and when it does start it makes a squeking sound like air being forced out of the crankcase right before it fires up. These things were known for flattening lobes on the cam. Would a flat lobe cause this by not letting the mixture enter the combustion chamber and building pressure in the crankcase causing oil to get forced passed the seals?

Thanks,
Mike

 

Look at the exhaust lobe as you slowly recoil the engine over. Some were real noticeable on wear,some still looked good but were at the later stages that started causing starting and running problems. Worst ones looked and acted like this.Bad Cam Pic - ATVConnection.com ATV Enthusiast Community

 

This thing runs great when you get it started, just that it takes forever to get it to run. I'm afraid this guy will burn his starter up if he continues to ride it. Can I access the cam to inspect it on these motors without pulling everything apart? And how much of a job is a cam replacement on this motor or am I better to tell this guy to send it out to some shop to do the job?

Thanks,
Mike

 

If it recoils starts easy,but electric starter takes a while,the problem could be the pick up coil distance.Something that's happened a lot on the 500 also. no spark to plug when using electric starter - Page 3 - ATVConnection.com ATV Enthusiast Community

 

It's almost impossible to get started with the recoil. It takes a good 30 seconds or more of cranking with the starter to get it to fire. This will kill the starter pretty quickly if he keeps it up. I tested the spark and I get good spark with both the electric start and the recoil. It acts as it is not getting any fuel but it will not even fire if given a shot of starting fluid which is off. Once started though, it runs very smooth and revs fine. Has me puzzled for sure. It almost seems like it is somehow not sucking in the mixture and is pressurizing the crankcase, kinda why the oil got forced out of the stator seal. I am hoping I can look at the cam to see if a lobe is actually flattened. The odd thing is, this machine was starting just fine and it went to this problem in one ride. I would assume a cam Would take time to flatten out.

Thanks,
Mike