12 Pro RMK Top End

[climbku86]

Hi guys. Working on my first top end rebuild. 2800 miles on the original top end. Cylinder is perfectly in spec and looks and feel great and I can still see the cross pattern. Pistons also look and feel great other than carbon buildup - no marks on either pistons or cylinder . It appeared to be well oiled. Valves were even pretty clean. There was some piston rock so I am glad I am doing this. After reading other posts I think I am leaning towards not honing. Is this the right decision? Should I do any sort of cleaning of the cylinder or head? I ordered a SK1396 Kit.

Second I lost the clamp that holds in the fuel line with the allen bolt. The OEM diagram doesn't give a picture so I assume 5254413 is the correct part but I am not sure.

My only other concert is with coolant and oil after everything is assembled. The service manual kinda sucks (Compared to my kawi manual) Any precautions to take?

Anything else I should look at while it open? The motor is still mounted so I can't get to everything.
Thanks

 

[climbku86]

I also forgot to mention. Since its nowhere near season. Should I wait to fire it up when done to I can break it in correctly or will starting be ok?

 

[rydningen]

Do NOT hone, remove carbon buildup in top part og cyl with scotch bright pad if any. Original pistons and wristpins, new fuelfilter.

If you have removed the oil tank, make sure to properly vent the system, this is very important.

Also, would check reeds, allmost guanrantee they are chipped/burnt.

 

[climbku86]

Thanks

I checked the reeds, indeed there was 2 chips.

 

[gtwitch]

my opinion only here but, I would put new Boysen Reeds on the factory reed blocks and new pistons/rings and ditto on scotch bright lightly the cylinders, clean cyls with soap and water and dry with compressed air and back together. make sure air is bled from oiling system and also coolant system. A trick that I use on the coolant bleed out is to raise the front end of the sled using a come along from an I bolt in my shop ceiling to get the top of the engine higher than the rest of the tunnel and all of the coolant system and then bleed from the port on the thermostat. This has worked very well for about 15 years or so in my endeavors. Start the engine after lowering it back down and run at idle and up to 3500 RPM until thermostat opens (feel the return side of the coolant on the rear/side of the tunnel then shut off and after it cools, raise front end again and bleed again and then run this warm up cycle again and while all this is going on make sure you keep an eye on the oil system for air bubbles. good luck and you should be ready for snow!
gtwitch in wyoming

 

[caddylover]

i used that wiseco sk1396 kit and you will need to ensure your piston to cylinder wall clearance is in spec. The wisecos are going to fit tight. I just finished rebuilding my 2012 800 Switchback and the stock ASSO-W polaris pistons rocked in my jugs as well. The wisecos fit spot on.



If you don't remove the oil pump, there is no need to bleed the system. Ensure you mix your first two tanks 50:1 and mark your oil reservoir so you can see if oil is going down in your tank. I turned up my oil pump 1 1/2 turns while i was in there. I took out my injectors and sent them out for cleaning since i was in that far with the engine out and on my bench.


Not a difficult job, just make sure you mark it all and torque to spec.

 

[climbku86]

All good information. I pinched the oil line 1/2 inch from the reservoir before i removed it so there should be no air in the line. I'll still take precaution. The engine appeared to be well oiled and it was slightly over the mark on the on the pump so I turned it up 3/4 a turn. I'm anxious to get her back together. I'm waiting on a wrist pin. Wiseco only sent one in the kit for some reason. Ill run 50/1 first tank and mark the reservoir to make sure its getting oil. I assume clean the (new) spark plugs after a tank because of the extra oil? The injectors - when i took them out I literally just pulled them out. Was this right? I have new o-rings for them but are they just held in by those o-rings? I and all of us have tooooo long of a summer so anything else while everything is accessible?

 

[caddylover]

the injectors just pull out with the fuel rail yes. Make sure you replace the green o rings in the block with the new ones that came with the Wiseco kit. There are torque specs that need to be followed so get a service manual if you don't have one already.

 

[climbku86]

Thanks for all the help

Pretty daunting for a first timer. Shes back together and fired right up. I've got coolant bleed but haven't run it enough to make sure its getting oil though i'm 99% sure there were no air bubbles. I'll check compression sometime after break-in. I'm just excited it started. Again thanks for the help.

 

[peaceofwork]

Did your ring end gap total more than 4 thou per inch of bore? I have seen a few Weisco installations whare the combination of a tight newish cylinder along with their recommended specs didn't last. On woren used cylinders whare the ring gap ended up being up around 20 thou they all worked out fine for a long time.
Any ways I guess it's done now so good luck with it report back on how it all works out in the future.

 

[mountainhorse]

I believe that the clip you want is part number 5254414.



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