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Discussion Starter #1
Hey folks,

have an xlt 93 580,

a year ago it started to run on 2 cylinders and started to analyze the sled. Cleaned carbs, changed carbs, changed coils, ext. didn't measure but two of us assumed that the crank was out of phase.

so started to pull it apart, found that a lot of silicone was used. And couple of bolts in the crank case were broke off.

when taking apart the fly wheel I noticed that the timing mark on the stator and the engine were not aligned and looks like the stator slipped. It seemed to be slipped a lot. It was fully on the retard side (rotated to the right).

Would that allow the engine to operate on two cycliner and back fire in the mag cylinder?

would there be any reason to set it up like this?

i am trying to save spending the money on new crank if I don't have too, I am planning to reassemble with new rings and try lining the timing marks back up.

anyone have any suggestions ?

i do have pictures but having issues with ipad and uploading them.

thanks,
 

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get a degree wheel from hiperf.com or denniskirk.com and check your top dead centers. from one piston to the next should be 120*

the full retard mode should just make the engine lazy low power.
 

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Did you check the compression? Are you sure it has spark on all 3? Are all 3 getting fuel? If everything else checks out, then look deeper.

You can do a crude test for crank twist by making a pointer out of a coat hanger, pointing across the clutch. Put each cylinder to tdc and make a mark on the clutch at the pointer. Then measure the distance between the marks with a flexible measuring tape. They should be the same distance apart.
 

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There is no way that the timing phase makes sense in your situation, unless it was assembled and sold to you that way.

Timing does not effect 1 or 2 cylinders, it effects all 3 the same. (which will appear to have a different effect if a crank is out of phase)

Stators do not 'slip'.. If it worked itself loose enough to turn on its own, the bolts would have fallen out shortly after it happened, not tightened themselves back up locking it in position there.

The crank may have already been out of phase, and the old owner turned back the timing to get 2 cylinders running instead of 1. But it would never have run well, and slipping more out of phase would only effect the center and PTO, never the recoil cylinder as that's what is directly connected to the same chunk of steel that the flywheel is attached to..

I have done a crude test like in the post above, and been able to tell a crank was out of phase.

My recommendation is to start with checking for spark on all 3 cylinders.
 

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I have checked crank index on 3 cylinder Polaris PWC by following the instructions below.
Bring your CEN piston to "true" TDC. (using a dial indicator to verify)

Then take a new pencil or dowel rod and drop it down the MAG spark plug hole. Mark the pencil with a razor blade laying flat across the head.

Now drop the pencil/dowel rod down the PTO plug hole and mark it.

The marks should be identical or within a couple thousandths of each other.


PROPER method is to use a dial indicator and degree wheel.

Using the dial indicator, find "true" TDC of each piston and mark it on the degree wheel placed over the engine coupler.

Each cyl should measure exactly 120* degrees apart.


Also on some engines fully retard maybe the spec. I have a 1994 Wetjet with a 50 hp brut motor that is setup fully retarded.

JJ
 

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Discussion Starter #6
Thank you all for the info,

Yes to gas, spark and compression.

I will try the tests above and get back with results.

thanks,
 

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I have checked crank index on 3 cylinder Polaris PWC by following the instructions below.
Bring your CEN piston to "true" TDC. (using a dial indicator to verify)

Then take a new pencil or dowel rod and drop it down the MAG spark plug hole. Mark the pencil with a razor blade laying flat across the head.

Now drop the pencil/dowel rod down the PTO plug hole and mark it.

The marks should be identical or within a couple thousandths of each other.


PROPER method is to use a dial indicator and degree wheel.

Using the dial indicator, find "true" TDC of each piston and mark it on the degree wheel placed over the engine coupler.

Each cyl should measure exactly 120* degrees apart.


Also on some engines fully retard maybe the spec. I have a 1994 Wetjet with a 50 hp brut motor that is setup fully retarded.

JJ
I've never heard of that method. But it sounds like it would work. I assume that when the center piston is at tdc the mag and pto pistons should be in identical positions, one on the way up and the other on the way down.

Just goes to prove that you learn something new everyday.
 

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Discussion Starter #8
So a little background on the sled.

friend owned it and a rod let go, we took apart and sent out for repair. That was around 6500 miles. Replace all top end and he ran for a couple years and I bought it. Ran for about 4 years and then it started to run not good. Boggy off the start, so I cleaned carbs, fouled spark plug...change plugs and coils...cleaned carbs again and again. It would get some good response at around 60 mph. Then started to change them around thinking something was wrong. Still the same.

a buddy of mine mentioned the crank could be outa phase. Did some research and started to tear it apart. That is when I discovered the timing marks not aligned. As far as i can read they should be lined up.

does this help or jar any other thoughts?

little too cold here to do any measuring...-29

will be at it this weekend.

thanks
 

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Discussion Starter #9
Hello everyone,

had ad the fire just blazing in the garage...ran some tests...
Fresh fuel
fuel to to all cylinders,
spark to all plugs,
120,120,115 psi,
new seals,gaskets and rings
checked the crank with dial indicator and degree wheel multiple times...pto-middle 120, middle-mag 121 and mag-pot 120 the specs are +\- 2 degrees so everything seems to be good.
Put it all together and it still doing same thing. Seems to be trying to fire on one or two cylinders. Blisters from pulling. Had it running really rough for about 3 min. Then stopped and can't get it to go again.....

need some advice....what am I overlooking?
What part and sequence do I need to check?

stator? CDI?

i am very frustrated and almost to the point of fire!!!!

if someone has some time and advice to work through this with me that would be awesome...

i can can add picture if needed.

thanks

Jeremy
 

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It sounds pretty similar to what I'm dealing with with my RXL's, losing fire and driving me crazy. I cleaned all the coil wires and coil terminals and put No Ox on everything and it seems to be running great now. I let it idle for a very long time and no more dying. I put a few miles on in the back fields and it didn't miss a beat. I just get that done and the other RXL is losing fire. I plan to do the same to that one. Those coil wires haven't been touched in 25 years and I think they get enough corrosion.oxidation to start losing contact. It's just too brutally cold to go for a ride for now. I think you should clean all your coil wires to rule that out.
 

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Discussion Starter #11
I will do that.
All coils are new.
The only electrical parts that are not would be stator and cdi box. Any info on those parts?

JJ
 

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new spark plug boots? I had a similar symptons in the past and that fixed it. I was getting spark with the plugs out, but it wasn't firing properly with them installed
 

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your dealer can do an ohm check on the stator to see if its good or not.
 

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I'm in a world of hurt here too. Just rebuilt this thing and I was very meticulous following the service manual to a T. But all I get is the odd pop. Which to me sounds like a back fire. Maybe I'll just drain the tank again. Perhaps there was leftover old gas down in the tank, enough to make this not run. I really hope so. There's not much more I can do. There is over 700 invested in parts on this and it's not mine so I feel like a dirt bag right now.
 

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Discussion Starter #16
Sounds very similar eyeballsdeep. Still, guys I need some suggestions. I will test stator tonight. With all the experience out there I can't scrap the the wedge!
 

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I am having the exact same problem. I have enough spare parts to build an engine. So I'm going to build a motor with a crank that has subpar pto bearing's and reuse the old gaskets, just to see if I can duplicate a motor that doesn't run. What do I have to loose. To me it sounds like the timing is out. As if the keyway is sheared. But I take the mag off and it's not. I have replaced every electrical component with know good working ones and I still get a pop but it sounds late as if it's firing when the exhaust port is open. I also have a slight carbon build up on the mouth of the carbs. A guy at my buddies shop said to switch the pto wires. He said he did that and the thing lit right up. I tried and got no diffrence.
 

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Hey bro, I am right there with you. I'm in tears right now. I'm frustrated as hell. I'm going to take the cylinders off and take it to work. Get the machine shop to dial bore gage this thing. I can only measure the very top with micrometer And the bottom. Maybe the cylinders are ballooned in the middle "?" Maybe they are tapered as hell. It's hard for me to take this stuff to work though I could get into some shit. Hopefully they can lend me a dial bore gauge. And get some real answers. That would be easier. But to me it sound like it's firing when open to the exhaust port. Do you have the same feeling with yours? I've clipped a 1/4" off my leads, but they looked fine. If you figure it out before me please post on my thread. I am very open to suggestions. Good luck.
 
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