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Discussion Starter #1
I am hoping I can get some help diagnosing my rzr. This is my first rzr and learning as I go. Thanks for your help.

I just got a 2013 900XP WE edition and its burning oil (1 qt after 100 miles/9 hrs.). Has about 4500 miles on engine.

I am running Mobile 1 0w40. I installed new plugs before the 100 miles and pulled the plugs after. The PTO side looks normal, the MAG side looks darker. No oil on plug, just looks rich.

Decided to do compression and leak down test.

Compression Test
Engine Warm (adjusted for altitude)
PTO..............MAG
140...............115

Engine Warm w/ 1oz oil added to cylinder (adjusted for altitude)
PTO.............MAG
168..............157

Leak down Test (Set tester to 50 psi)
PTO...................................MAG
50 psi to 48 psi.............50 psi to 10 psi

PTO cylinder had no air leaking that I could hear anywhere.
MAG cylinder had alot of air coming from intake and dipstick. There is also some oil in this intake horn.

My best guess is that the MAG intake valve needs adjusted. I am assuming that the air from the dipstick is actually coming from the intake valve and not rings. I also think that the leaking intake valve probably pushed up the valve seal and its causing the high oil consumption.

Does this analysis sound right?

Also I hear that at some point Polaris switched from separate shims and cups to cups with shims built in. Does anybody know if you can tell before removing valve cover? maybe via engine serial #?

Thanks
 

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Discussion Starter #2
BTW the Compression numbers may be a little low as I don't think my helper held the throttle open during test. I know this can lower the numbers a bit. Just not sure how much.
 

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Decided to set the valve lash today. Not too difficult just takes time to remove rear box.
After removing the cams I decided to do leak down test again. This should show if there are ring problems since the valves would be closed with no cams interfering.

The PTO was still at 4%, but now the MAG is at 8%, which is WAY better than the 80% it had. Kinda proved the intake valves are too tight.

All exhaust were in tolerance. All intake were tight. Dealer swapped my shims for the correct ones. The PTO intake valves had 0 tolerance but as seen in the leak down they were closed, but just barely.
The MAG intake valves had less than 0 tolerance so I had to try a few different shims just to get a gap to measure. Had to go from 225 shim to 200. Now all intake valves are in spec.

It now starts right up! Before I had to hold throttle open a little just to get it to start and keep holding until warm. Hope this also helps with reducing oil usage.
 

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Took a 80 mile ride yesterday. Still using a half quart every 40 miles. Ride was trails mostly (15 to 30mph). So I decided to drain the Mobile 1 0w40 and put in Rotella 15w40 T5 (synthetic blend). Did a 25 mile highway ride (40 mph avg). Burned 1/2 quart, ouch that is worse! Had to think about it over nite. I figured the higher speed was burning more oil.

Decided to do a cold compression test today (the right way with throttle held open). I was surprised how much better the plugs looked after the valve lash adjustment. Both had the normal brown tinge and no more black carbon. Both PTO and MAG cylinders are at 200 psi, way better than before.

Since it was looking like a rebuild was in my future due to oil burning I decided to try some Rislone Ring Sealer. I put in 7oz and did the same 25 mile highway ride. Burned only 3oz verses the 15oz I was burning before, much better! Not sure if this will last, but will do some more miles to see. Hopefully the combination of Rislone and Lucas in the fuel are cleaning up the carbon. Maybe the rings were carboned up and sticking in the grooves. May be wishful thinking, time will tell.
 

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Discussion Starter #6
Yeah I might try that. I have done a few different rides and am seeing about 2.5 miles per oz of oil (15w40) now. That means every 40 miles it’s using 1/2 qt. That’s with Rislone, but not sure how much has burned off in the last hundred miles.

It is confusing as leak down test looks good and compression is 200 in both cylinders. Spark plugs look good after valve lash adjustment. Looking down the intake I don’t see any oil on valves. You can see smoke when reving engine but its not a ton. I think same happens on deceleration.

Where is the oil burning from? With good compression can rings still be that bad? Valve seals? Hate to do a rebuild as it runs good, starts every time.
 

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So I did a Seafoam treatment last nite using Seafoam and spray Seafoam.

Put 3oz in crankcase and 10oz in fuel tank and drove for 10 miles.
Then sprayed 1/2 can in intake while running at 3000 rpms. Lots of smoke!
Then sprayed heavy dose in intake and shut off engine and let it hot soak for 15 min.
Then drove for 10 miles.
Then removed spark plugs and put 1oz in each cylinder and topped off with a little spray Seafoam. Jacked up rear of RZR to make cylinders level.
Let soak for 24hrs.
Crank engine to clear so no risk of hydrolock.
Install plugs and run for a few minutes. A lot of carbon coming out of exhaust.
Then drove for 10 miles.
Then did oil change. Put another 3oz in crankcase with new oil.

Now just need to drive for awhile to see if helps reduce oil consumption. Hopefully if it’s oil rings they will free up. Sure is fun experimenting 😀
 

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Sounds like you’re on the right track.
My 2012 900 XP needed valve guides at about 2000 miles. It was using about the same amount of oil as you describe.
Breezing through this post I didn’t see if you’d checked that as well.



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Discussion Starter #11
Sounds like you’re on the right track.
My 2012 900 XP needed valve guides at about 2000 miles. It was using about the same amount of oil as you describe.
Breezing through this post I didn’t see if you’d checked that as well.



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I haven’t pulled the head. I set the valve lash and now wish I would have gone with my original plan of replacing valve seals. Plan was to use leak down tester to hold valves up and replace seals. It would have given me opportunity to see how much play was in valves... oh well.

i don’t see any oil on the valves, but maybe it’s so clean I can’t tell. Should see if the seafoam helped this weekend.
 

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Just like RickRou56, I had a similar issue with my 2012 900XP. Mine started around 1,500 miles. I wasn’t burning oil, I was blowing it out of the breather hose. I didn’t see any signs of dust beyond the air filter, compression & leak down numbers looked good. Mine turned out to be valve guides.


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Just like RickRou56, I had a similar issue with my 2012 900XP. Mine started around 1,500 miles. I wasn’t burning oil, I was blowing it out of the breather hose. I didn’t see any signs of dust beyond the air filter, compression & leak down numbers looked good. Mine turned out to be valve guides.


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Did you do a full rebuild or just the head?
 

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My cylinder showed a couple of scratches so I ended up doing a full rebuild. I installed an Alba 935 kit and cams. I figured I would make light out of a bad situation and get some more power in the process. I did screw up and took the head to a local engine builder to disassemble and check out. They said everything was in spec, still had the problem. I had to pull the head back off and get the guides replaced.


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My cylinder showed a couple of scratches so I ended up doing a full rebuild. I installed an Alba 935 kit and cams. I figured I would make light out of a bad situation and get some more power in the process. I did screw up and took the head to a local engine builder to disassemble and check out. They said everything was in spec, still had the problem. I had to pull the head back off and get the guides replaced.


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Did they have to cut valve seats after replacing guides? Just wondering if guides could be a diy project.
 
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