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99 Sportsman 335 won’t start

1185 Views 5 Replies 3 Participants Last post by  micoviso
this is my first post I recently bought a 99 sportsman 335 and it’s my first 4 wheeler so i’m still learning. the 4 wheeler had been sitting in a barn for at least a year and a half and the guy who owned it before me took it to a shop and they couldn’t figure it out so he just parked it in the barn. So far I have replaced the cdi unit, the stator, ignition switch, fuel switch, carb, and choke cable. i know i have to replace the brake light switch and probably the rear and front master cylinders. i have spark and fuel and i got it started for a few mins before it died. now it won’t start, it sounds like it’s about to and seems super close but won’t. when attempting to start it, it does backfire also. so i’m pretty confident i re timed the valves to the correct specs and still won’t start. i did a compression test and it read 25, so i’m thinking it’s the pistons. does anyone have any other suggestions or knows if i should just buy a complete new piston kit.
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How do you re-time the valves with out replacing the camshaft? I can re-time the cam and the spark, but valve timing is determined by the cam profile. Now did you check the compression while holding the throttle wide open? If the shop couldn't figure it out, they were a piss poor shop. I don't believe a vehicle ever left my shop that I didn't know what the problem was. Many left not fixed, but that was the owners choice. Some were just not worth the expense, but I fixed many that if were mine would not have been fixed. I personally felt it wasn't worth the expense, but some expressed a sentimental attachment. I won't argue with sentiment - I just fix it if the owner says it's worth it.

So......... based on what you have already done, get a cylinder leak down test done to find out where the compression is going, then you can decide on a course of action.
I mean we did the valve adjustments not the timing, (my cousin is the mechanic and i’m still learning). and yes the throttle was wide open. i’m pretty sure the shop was really bad because it since has closed and when i got the 4 wheeler, and a good amount of things were disconnected, missing bolts or just completely not there and i received a box of random nuts and bolts to. the guy said they told to come pick it up cause they couldn’t figure out what was wrong with it. and i will def do that test, thank you!
I’m hoping for your sake this isn’t your problem, but in case it is, has anyone figured out how to get a camshaft for the 335? They’re not available anywhere I’ve seen. I’ve got the same model and when I bought it, the previous owner told me a “shop” told him it needed a cam. When I tried to find one, I couldn’t. Thankfully, my problem turned out to be carburetor butchery from the “shop” and I was able to correct it. But I’d sure like to get my hands on a spare cam if I could.
Try Web Cam HERE - they may be able to repair and regrind an old cam
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