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It appears that my 11’ 900xp is consistently burning oil and none appearing on the dipstick, i pitched this unit about 8-9 months ago and it has about 3500-4000 miles on it. What could my issue/issues be? Possible rebuild?


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The Lone Rzr
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They had cheap valve guides
Might just need fresh top end
Leak down test would be best
 

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Mine passed leak down, but when I rebuilt the rings were worn way past spec. I have little faith in leak down after seeing that.
 

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My 2013 900xp is hard to start cold and is using oil. After engine has warmed to normal operating temp it starts normal/easy. It has 4500 miles and 463 hours. I ran a leak down test. The leak down test should be completed when engine is at operating temp. Just to see what it had, I ran a test on a cold (85* air temp) engine, then a test at operating temp. It failed the cold test, having about 60% leak down; but when at operating temp it had less than 2% leak down. When at operating temp it held pressure, which tells me the head is probably ok? I assume probably rings are allowing air to bypass when cold, but when at op temps the rings seal and hold compression. I’ll find out what’s going on when I pull the head and cylinder off.
 

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The Lone Rzr
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My 2013 900xp is hard to start cold and is using oil. After engine has warmed to normal operating temp it starts normal/easy. It has 4500 miles and 463 hours. I ran a leak down test. The leak down test should be completed when engine is at operating temp. Just to see what it had, I ran a test on a cold (85* air temp) engine, then a test at operating temp. It failed the cold test, having about 60% leak down; but when at operating temp it had less than 2% leak down. When at operating temp it held pressure, which tells me the head is probably ok? I assume probably rings are allowing air to bypass when cold, but when at op temps the rings seal and hold compression. I’ll find out what’s going on when I pull the head and cylinder off.
When is last time you checked valve lash?
Your symptoms indicate valves need adjusting
Most likely needs valve guides for the burning oil
 

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I bought the RZR in 2018. To my knowledge valve clearance has never been checked. I see in Chap 2 where it should be completed @ 200hours or 3200 miles, whichever comes first. Looking back at my records, it had 1500 miles at purchase and unsure of the hours but a year later it had 2330 miles and 282 hours (I didn’t record the hours first service I completed). And I’m the 3rd owner.

So, looks like the next thing I’ll do is “Valve Clearance” inspection. I already had in mind a top end rebuild, which it might require, but valve lash might fix the problem!

I’ll report back after the inspection. It’ll probably be in a couple weeks as I’ve my Jeep in my shop now and must complete the work on it first.

Thanks
 

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Yes valve lash is cold starting issue. It will be the intake valves. You will need a shim kit or possibly your dealer will swap you shims.

If going that far you might consider replacing valve seals. They only cost about $40 and will stop some of the oil burning. Here is a video I did on how to replace seals and how to build spring compressor. The KibbleWhite seals are nice.

 

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Yes valve lash is cold starting issue. It will be the intake valves. You will need a shim kit or possibly your dealer will swap you shims.

If going that far you might consider replacing valve seals. They only cost about $40 and will stop some of the oil burning. Here is a video I did on how to replace seals and how to build spring compressor. The KibbleWhite seals are nice.

Interesting!! Would make it much simpler!!

A few questions.
-looks like you have your leak down manifold connected. I assume that’s to keep compressed air in the cylinder so the valve remains seated where it won’t fall into the cylinder? How much pressure do you have on the gauge?

- Does the valve spring sit on top of the seal

- did you make a complete video of removing the retainer, spring, and seat? Then replacing them?

-would there be carbon buildup where the seat sits on the head? If so, how do you clean that?

thanks a lots!! This is very helpful and encouraging.
 

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The valves spring sits on top of seal.
I did not make a full video as there are many others out there.
No carbon buildup, that will be on the exhaust valves and you would have to remove header to see it.

I tried EVERYTHING before my rebuild. I figured what the heck. I ran Seafoam through the gas for 100 miles, then filled cylinder thru spark plug hole with Seafoam, let it sit overnite.. in hope it was a stuck ring. Even ran Marvel Mystery oil thru it. Tried ring seal treatment which worked great… for 100 miles, then back to burning oil. Last I replaced the valve seals. They helped, but I was still burning more oil than I wanted. I was burning a quart of oil every 60 miles. No real visible smoke, but you could smell it. My compression test showed 185 in cylinders and leak down was around 10%. All within specs.

The rebuild showed me that my rings were work 3 times more than spec. The intake valve guides were shot. I ended up with about $2000 in parts for full rebuild.

If you are burning less than I was you might live with it for awhile, but expect a rebuild in you future.
 

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The valves spring sits on top of seal.
I did not make a full video as there are many others out there.…

The rebuild showed me that my rings were work 3 times more than spec. The intake valve guides were shot. I ended up with about $2000 in parts for full rebuild.

If you are burning less than I was you might live with it for awhile, but expect a rebuild in you future.
Did you rebuild the head yourself? How about the cylinders? Did you rebuild just the upper? Or lower also?

I’m about 80% complete on my Jeep then I’ll start on the RZR. I know it’s one of those deals where you really don’t know until you tear into it!

Thanks for all the info.


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Local machine shop did head. New valve guides, valves, and valve seals ($600). I also put in new valve springs.

I bought new cylinder, pistons, and rings.
I did complete bottom end (bearings, oil pump, both chains). Cam and crank were reused.
 

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When is last time you checked valve lash?
Your symptoms indicate valves need adjusting
Most likely needs valve guides for the burning oil
Checked valve lash last night and all valves are right on specs. Next step is to pull the head and leak check valves. After that, pull cylinder and check rings. Looking more and more like rings are at fault. One thing I found as a mystery and REAL surprise is the breather hose from crankcase vent to intake housing was not inserted in the intake housing, but lying in-between engine and housing well out of sight. And the end of the hose was caked with dirt, mud, and oil! I don’t know how long it’s been like that. Stands to reason that dust, dirt, and various other contaminants entered crankcase. I always wondered why the K&N intake filter was dirty on that side. Now I know!!
 

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