[Traut27]

I have a 2012 rzr 900xp that I bought last year. It always smoked white until warm then it would stop. Eventually decided to rebuild the top end. Figured I had a bad head gasket. When I started taking it apart I realized it had obviously been rebuilt not too long before. Cylinder looked newish, and so I replaced the head gasket, honed cylinder, new rings, had the head surfaced/decked, new valves, seals, alba chain tensioner etc. Finally got it back together and it smokes worse than it ever did, it does not stop even when warmed up. Yes I used new gaskets/studs etc and torqued everything to sequence and torque. Kind of lost here. Any suggestions? I dont know what I would do differently if I rebuilt it

 

[Traut27]

Compression on both sides at wot is 155

 

[dartersracing99]

I hope you used a ball hone made for nikisil cylinders, and checked the valve guides.

 

[dartersracing99]

Also dont use synthetic oil in new engines, recd break in oil.

 

[Traut27]

Also dont use synthetic oil in new engines, recd break in oil.

I originally had synthetic in for initial start up before I realized that mistake and replaced it with non synthetic. I cant say that I checked valve guides.. just swapped the seals out when I replaced the valves and lapped them

 

[DesertDuo]

Intake valve guides are probably worn. Most oil usage is from those and rings, but you replaced rings. I checked my valve guides before rebuild. I set piston high in cylinder (so if I dropped the valve it would be retrievable. I removed valve spring and wiggled the valve. The intakes had quite a bit of movement, the exhausts had none. The reinforced that the intake guides were worn. You could try this before removing the head again.

 

[Traut27]

Just scoped the cylinders, there was alot of oil in both sides.. I'm going to start digging back into it tomorrow, I'll start with the guides. Thanks

 

[Traut27]

Intake valve guides are probably worn. Most oil usage is from those and rings, but you replaced rings. I checked my valve guides before rebuild. I set piston high in cylinder (so if I dropped the valve it would be retrievable. I removed valve spring and wiggled the valve. The intakes had quite a bit of movement, the exhausts had none. The reinforced that the intake guides were worn. You could try this before removing the head again.

How can you tell if they are bad? Just if there is slop in them I assume? Can there be any wiggle in them or are they suppose to be completely tight?
Also, can head studs be reused or is that a one time torque deal like gaskets? They have about 5 mins on them..

 

[Traut27]

Exhaust valve guides were 100% shot.. sending out to have new ones put in.

 

[DesertDuo]

How can you tell if they are bad? Just if there is slop in them I assume? Can there be any wiggle in them or are they suppose to be completely tight?
Also, can head studs be reused or is that a one time torque deal like gaskets? They have about 5 mins on them..

No wiggle in the valves.
Studs can normally be reused, but if they are bolts they cannot.

 

[Traut27]

Just wanted to follow up, sent the head off to alba for exhaust valve job and cleanup, re shimmed and good to go. Thank you everyone for suggestions