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predator no start

29K views 81 replies 6 participants last post by  pink63impala 
#1 ·
have a 05 predator 500 working on. fella brought it to me cause it wasnt running. it had a tight exhaust valve. had valves adjusted, drained fuel and put fresh 93 in it. took carb off and cleaned it. changed battery. plug looked new. cant get it to fire up. tried pushing and pulling it with my other 4 wheeler, but it wont bust off. gonna try one more new plug but after that i dont know. has 150 psi on compression now. plug is firing,cant tell if its weak though.. any help apreciated.
 
#4 ·
who did the valve shim adjustment?
are you sure timings on now? how were the intake valves? usually those are the ones that need the most attention. when you pulled the plug was it dry or wet? if dry then your not getting gas with a backfire out the carb i would guess your timing is off and if the timing is off i would guess its not looking good for your valves. i would pull your plug on the mag side put the T in the little notch and pull the valve cover and check your timing marks. i wouldnt try cranking on it until you make sure timing is on 1 tooth will crush a valve into a piston and toast a head.
 
#5 ·
Ok I'm looking at the timing.and at another thread on here..I have the timing mark to the left of the t lined up,on the notch.my intake or rear cam marks looking at the quad from the right side are at 12 and 9. The exhaust is at 12 and 3.and looks like the lobe is opening the exhaust valves.from what I read on the other timing thread the lobes should be facing outwards and are both came supposed to be at 12 and 9 ?
 
#7 ·
ok your timing is off. you need to be on the T mark not the line next to the T. then front the right side of the quad(or clutch cover side) intake will be at 9 and 12 and exhaust should be 1 tooth above 9 and one tooth past 12 if the marks are at 9-12 on intake and 12-3 on exhaust your timing is off and prolly have a bent valve now. i am looking for the picture to show how it all lines up as soon as i find it ill post it up for you
 
#8 ·
here is what you cam timing should look like







 
#9 ·
thanks leo i knew you would be faster at posting them since i was going to steal your pics anyways...lol between you and me we are going to get these predators all straightened out then we wont be needed anymore. maybe we should keep one little secret so they dont know everything.
 
#11 ·
yes very easy to do. could you post a picture of the t through the timing hole and also a picture of how your cams sit and maybe we can help more.
 
#13 ·
theres 3 gold links they line up on the top timing marks on the cams and on the timing mark on the crank sprocket but you have to pull clutch cover to line the bottom one up and you have to pull the sprocket thats in front of that sprocket to see the mark. theres actually 2 sprockets on the crank on that side of the motor. on runs your timing the other runs your clutch basket.
 
#14 ·
if you want to make sure it is all right turn it over and over until the gold links line up on the cams and the t in in the window. if the timing is wrong i would do as josh suggested and pull the clutch to make sure all 3 gold links line up and then re check my valves.
 
#16 ·
no the gold links just let you know if you have all three good. it also allows you to check if the keyway on the flywheel is intact.

the center bolt is just a cover. you have to use a thin tipped screwdriver to release tension it is behind the nut. it might be easier to pull the 2 outside bolts and just have it loose. just do not let it drop down where it will come of the crank gear at the bottom. then you will have to pull the clutch cover and clutch to get it right.
 
#17 ·
by the way, that timing is so screwed up only a polaris certified mechanic could have done that!
 
#18 ·
seriously though, it is one thing to bumble through your own engine blindly, but to charge top dollar at a race shop there is no excuse. you need to get your money back. they could have googled a service manual for free. you need to print out the correct timing and take it to them and say thanks for almost ruining my engine. good thing it did not start.
 
#20 ·
ok here it goes. as far as that timing is off i have to say i would actually pull the top end and have the valves checked before going any further on getting it running. If a valve is bent right now you can probable get away with replacing the valves and having them lapped in. if they are bent and you get it running you run the risk of putting a valve into the piston and toatsing the head, piston and maybe even the cylinder. that is up to you tho. heads 450+ piston is 140 stock size valves are 60 for the set and then having them lapped in by a machine shop 75 an hr i would guess. stock head gasket base gasket 40 bucks knowing its not going to cost you a 1000 to put the motor back together priceless.
 
#21 ·
i have this motor down to a science i can pull it apart and put it back together in about an hour with all parts in hand...lol to bad your so far away.
 
#23 ·
those gold links are not where they need to be. if you are not going to pull the clutch then you need to line up the gold links right on where they should be. it can take up to 27 revolutions of the engine before the gold links are where they need to be and it is at top dead center.

that is another story though.

just line up the t in the window with both the top gold links at approximately 12 o clock. then line the cams up exactly as in the picture i gave you from the service manual. if you let the bottom of the chain loose at any time then you will need to pull the clutch to get it right. any other way will just be a shot in the dark.
 
#24 ·
yes i would get the timing right and check it out before i tore it down.
 
#25 ·
if you do not have the links in the right spot on top and the t in line with the notch in the window you will not get it timed right very easily. i guess you could eyeball it but i would never do that and i would not recommend it
 
#26 ·
leos a chicken i did mine the first time lining the T up and then just pulling the cam chain around until the gold links were up then set my cams.....oh but i pulled my motor back apart after 15 mins cuz i didnt like the way my motor sounded. i recommend pulling the clutch and everything to set the timing the right way i did that the last time and it actually took less time to do it right then it did to set it up and hope it was right. piece of mind is priceless when a replacement motor is 1400 or more.
 
#27 ·
i agree on all accounts but if he is not going to pull the clutch. he should at least line up the top 2 gold links and the t in the window, wouldn't you agree?
 
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