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Discussion Starter #1
So this quad has good spark, compression is about 92 psi. I gave it a shot of starting fluid, but, it doesn't start. The "cranking" speed seems to speed up a bit when the ether goes in, tho. But it won't fire.
I checked the valves and the ex seems to be good at .009/.010. The intakes are tight at .003/4. I think spec is ex ..010 and int .006. Also, when I crank it over, I can hear a loud clack that comes from what sounds like the R side and kinda low and back on the motor. It seems like it does it about once per engine revolution. NOt sure on that, tho. Would the tight intakes make it not start at all?
Thanks!
 

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If the intake valves have clearance (any clearance) it will not affect starting - I would suspect, weak spark or park at the wrong time - start with a new spark plug and use a timing light to verify spark with the plug in the cylinder - if the spark does not jump the gap, the timing light will not flash - once you have verified spark and spark at the right time, you are down to compression, fuel, air and fuel and air in the right ratios.
 

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Discussion Starter #3
I have a spark tester and it has very strong spark. Is it a timing thing? How does one adjust the timing? Or is it even adjustable?

If the intake valves have clearance (any clearance) it will not affect starting - I would suspect, weak spark or park at the wrong time - start with a new spark plug and use a timing light to verify spark with the plug in the cylinder - if the spark does not jump the gap, the timing light will not flash - once you have verified spark and spark at the right time, you are down to compression, fuel, air and fuel and air in the right ratios.
 

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The only way timing can be off is due to a faulty component - most frequent cause of the timing being off is a sheared flywheel key. Timing can be easily and quickly checked by removing the spark plug and using a soda straw to check the position of the piston - using the straw, rotate the engine to determine when the piston is at TDC - when the piston is at TDC, the mark on the flywheel should be visible in the inspection hole - if the mark is not visible, rotate the flywheel until the mark is visible and recheck the position of the piston - if the piston position is more than 5 degrees off of true TDC, then the flywheel is out of position and needs to be investigated.
 

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Discussion Starter #7
That's on the L side of the engine. The noise is coming from the R side. I think.
What is the "recoil cover?" Did you mean starter rope? There isn't a pull start on this machine.
Maybe the pulse coil fell off and is bouncing on the flywheel under the recoil cover?
 

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OK - I didn't check the particulars and most Polaris models have the ignition and stator on the R side - the predator is on the L side - I stand corrected.

The cam drive is on the R - perhaps the cam chain has worn out and is jumping teeth - maybe it has to do with the auto-decompressor - it's on the RH end of the exhaust cam?

Let us know what you discover.
 

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Discussion Starter #9
I did the straw trick and the timing marks lined up at tdc. When I crank it over with a ratchet, right before tdc it tightens up and doesn't feel very smooth. I gotta change the oil and filter anyway, so I'm gonna drain the oil and pull the clutch cover.
 

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Getting tight at TDC coupled with the clunking from the R side, I suspicion the cam jumped time and you have a valve kissing the piston. If that's what's happening, you will need to check the cam chain tensioner mechanism, install a new cam chain and possibly (more likely than not) you will need at least two new valves. You will not know the situation until the valve cover is removed and the cam timing checked.
 

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Discussion Starter #11
I will. I have the clutch cover off, but the battery is dead. Doh! So, its on the charger. The cam chain seems very tight, but, I'll know more when I can crank it over.
Thanks for your input! (y)

OK - I didn't check the particulars and most Polaris models have the ignition and stator on the R side - the predator is on the L side - I stand corrected.

The cam drive is on the R - perhaps the cam chain has worn out and is jumping teeth - maybe it has to do with the auto-decompressor - it's on the RH end of the exhaust cam?

Let us know what you discover.
 

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Discussion Starter #12
So I found the source of the noise. I started to suspect the starter one-way clutch. Seen this many times. The polaris tech told me that it's most likely the tight intakes is why it won't start. He said they will start at .004, but probably not at .003. And with a new plug in it, and a shot of ether, the cranking speed picks up noticeably like it's really trying to start. Those are both steel and alumnum bits in there.

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137226
 

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Polaris tech is wrong - they will start at -.0005 clearance, but they are hard to start - at -.002 the engine can start, but it needs needs to be spun faster than the on board starter motor will turn it. On a manual transmission machine, they can be pull or push started. I have seen YZ250F Yamahas (5 valve engine) run with a valve at -.004 (that's open 4 thousandths of an inch when the engine is cold ans at rest). When the engine is spun at a higher speed than the starter motor will turn it, the compression rises sufficiently to get it started and once running, compression will blow the valve closed, but eventually the clearance will decrease to a point where even push starting will not get the job done and the valves have to be adjusted to get adequate clearance for ease of starting.
 

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Discussion Starter #14
I wonder if the desintegrating starter sprague is slowing the starter down and therefore not starting? But, regardless, the valves need to be adjusted and the starter clutch will need to be replaced. Ordering parts momentarily.
 

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Discussion Starter #15
I have about 7 different pullers. And at least 3 are for Polaris machines. Buuuuuuut, not for this one! :poop:
I have one for an old yamaha dirt bike and it fits at least 100 other models.
Rant over. :cool:
If I ever post up here that I'm thinking about buying a Polaris quad......somebody find me....and shoot me! ;) :ROFLMAO:
 

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Discussion Starter #16
So, heres the lates, latebird. The metal shavings and debris came from some of the bolts on the back of the flywheel. So, I sent back the new starter clutch kit that I bought. I replaced these bolts and put red loctite on them.
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So, here's a real head-scratcher.....I reshimmed the intake valves and they are in spec now. I went a bit on the loose side, cuz I know they will only tighten up. Now, trying to time the camshafts, etc, this is puzzling to me. Look at the cams. The ex is on the R. Those white dots are exactly how the service manual says they should be. But, in the 2nd pic, look at the lobes. They are almost in identical position. That would have the all the valves opening at the same time! As per the manual, with the dots in proper arraingment, the lobes should be at approximatley the 10 (int) and 2 (ex) position. These are not even close. I have no idea how they could be like that. And, sadly, I didn't take any pics before I took the cam chain loose. Dang it, my bad!
Got any ideas on the wth is going on here?
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137340
 

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OK - the guy who designed it is smarter than both of us combined, but use logic to put this together.

What value did you torque the starter clutch bolts at?

First thing to do is assure the piston is at TDC - then set the cams in place as pictured looking at the key slots and not the white dots (don't pay any attention to the brass links either as this pic is out of an 03 manual, but the timing procedure is the same for the 05)
137357

With the cams in place the lobes should be at the approximate 10 (in) and 2 (ex) o'clock positions (as viewed from the RH side of the engine) - when satisfied with the position and before installing the chain tensioner, with the spark plug out rotate the crankshaft (clockwise from the right side or CCW from the left side) gently by hand - if the chain is loose enough to jump teeth, it should be replaced, but you can just push on the tensioner with a finger or socket extension to prevent the chain from jumping - rotate the crankshaft two full turns and bring back to TDC - if the valves did not hit the piston or each other and the cams are in the same position after rotating as they were prior, then the timing is correct. The only way to be more precise would be to install a degree wheel on the crankshaft and index it for TDC - install dial indicators on the cam lobes or valve lifters (depending on the procedure being used) to find the degrees at which the valves open and close. With non-adjustable cam sprockets you are limited to being close to the design specifications.

Let me know if this gets you where you need to be.

I just worked on a Triumph 865 Speedmaster vertical twin with a 270 degree crankshaft (pistons arrive at TDC 90 degrees apart and the cams rotate the opposite direction of the crankshaft. Not only that, but the cams are timed on the LH side while the crankshaft is timed on the RH side. Because the cams rotate opposite of the crank, the lobes had to be at 7 o'clock on the exhaust and 5 o'clock on the intake with the LH piston at TDC. When the crankshaft was turned clockwise the cams rotated CCW - the intake valve started to open immediately as the piston moved away from TDC - it took me the biggest part of a day to figure it out and I had the factory manual, but the manual leaves many details (such as which piston has to be at TDC - I wrote that in the book as I figured it out) - traditional vertical and V-twins have both pistons come to TDC at the same time - one on compression and one on exhaust.
 

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The flywheel puller you needed (33mm x 1.5 Right Hand Thread Flywheel Puller (Female)) also works on most current GSXR600, GSXR750, GSXR1000 & GSXR1300 Suzuki Street Bike Models, (2006-Present) Suzuki 250 OZARK 4 Stroke Quad Models, Honda (2006-2013) CRF150F 4 Stroke Dirt Bike and the CN250 Helix Scooter, Yamaha YFZ450 Quads & (2004-Present) WR450F 4 Stroke Enduro Models, KTM Electric Start Single Cylinder 620cc, 625cc, 640cc, 660cc, 690cc & LC4E 4 Stroke Engine Models, Polaris (2003-2007) PREDATOR 500cc 4 Stroke Quad Models and most Kawasaki 2 Stroke JET SKI 1200 STXR & ULTRA 150 Models. Knowledge is power and I got one of these pullers specifically to pull the flywheel off a CRF150F and now I have one that works on all the other models. I just took in a GSXR600 - I don't think I will have to pull the flywheel, but if I need to, I know that I have the puller for it.
 

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Discussion Starter #19
Yes I did all that. When I was turning the engine over by hand that's when I noticed that the cams were opening both intake and exhaust at the same time. That's when I knew something was wrong. So, looking at my pic,think of the edge of the table as the top of the cylinder head. The white dots are the dimpled marks. I put paint on them so they're easier to see. The dots are really close to where they're supposed to be. 9 and 12. Not exact mind you, but close enough to see that the lobes aren't even close.
137359


OK - the guy who designed it is smarter than both of us combined, but use logic to put this together.

What value did you torque the starter clutch bolts at?

First thing to do is assure the piston is at TDC - then set the cams in place as pictured looking at the key slots and not the white dots (don't pay any attention to the brass links either as this pic is out of an 03 manual, but the timing procedure is the same for the 05)
View attachment 137357
With the cams in place the lobes should be at the approximate 10 (in) and 2 (ex) o'clock positions (as viewed from the RH side of the engine) - when satisfied with the position and before installing the chain tensioner, with the spark plug out rotate the crankshaft (clockwise from the right side or CCW from the left side) gently by hand - if the chain is loose enough to jump teeth, it should be replaced, but you can just push on the tensioner with a finger or socket extension to prevent the chain from jumping - rotate the crankshaft two full turns and bring back to TDC - if the valves did not hit the piston or each other and the cams are in the same position after rotating as they were prior, then the timing is correct. The only way to be more precise would be to install a degree wheel on the crankshaft and index it for TDC - install dial indicators on the cam lobes or valve lifters (depending on the procedure being used) to find the degrees at which the valves open and close. With non-adjustable cam sprockets you are limited to being close to the design specifications.

Let me know if this gets you where you need to be.

I just worked on a Triumph 865 Speedmaster vertical twin with a 270 degree crankshaft (pistons arrive at TDC 90 degrees apart and the cams rotate the opposite direction of the crankshaft. Not only that, but the cams are timed on the LH side while the crankshaft is timed on the RH side. Because the cams rotate opposite of the crank, the lobes had to be at 7 o'clock on the exhaust and 5 o'clock on the intake with the LH piston at TDC. When the crankshaft was turned clockwise the cams rotated CCW - the intake valve started to open immediately as the piston moved away from TDC - it took me the biggest part of a day to figure it out and I had the factory manual, but the manual leaves many details (such as which piston has to be at TDC - I wrote that in the book as I figured it out) - traditional vertical and V-twins have both pistons come to TDC at the same time - one on compression and one on exhaust.
 
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