I am in the process of getting all the parts I need to put a new top end in my 2002 Summit 800. has 3000 miles on it, runs great but just want to prevent problems in the future and looking to get a little more power. I am getting the 20HP Drop in Kit from RK Tek so I am getting the new pistons, rings, head, needle bearings from there. I am getting the circlips from ski doo. I already have the shop manual on CD that I printed out. Is there any secrets or things I should lookout for when doing this, any tricks. Also what special tools will i need, already have a torque wrench and basic tools.This is the first time I have ever torn into a rotax engine, I did a john deere snowmobile engine once but that was much simpler. Any input or links to go too would be great. thanks
New Top End, First Time
- Thread starter 02SummitX800
- Start date
C
cjgodden
Well-known member
I would suggest you split the cases and regrease the crank bearings while you are at it, with 3000 miles it would really suck to do a drop in kit and end up loosing a crank bearing shortly after.
As far as tricks, a 30 dollar cir-clip installer makes life easier, you can do the cir-clips with out on but it is just easier. Be careful pulling the old pistons, the needle bearings are cageless and will fall everwhere. make sure you can account for all of them after you pull the pistons off the rods. there are 28 per piston.
Splitting the bottom is easy, and you can buy the isoflex grease online for over half the price you can get it from the dealer. ski-doo recommends you regrease the crank bearings every 2000 miles so you are over due allready. make sure you torque every thing to spec and use a case sealer on the case halves( like honda bond, yama bond, three bond case sealer) and you will be fine. dont forget to fill the waterpump cavity with two stroke oil and use two stroke oil for assembly lube.
As far as tricks, a 30 dollar cir-clip installer makes life easier, you can do the cir-clips with out on but it is just easier. Be careful pulling the old pistons, the needle bearings are cageless and will fall everwhere. make sure you can account for all of them after you pull the pistons off the rods. there are 28 per piston.
Splitting the bottom is easy, and you can buy the isoflex grease online for over half the price you can get it from the dealer. ski-doo recommends you regrease the crank bearings every 2000 miles so you are over due allready. make sure you torque every thing to spec and use a case sealer on the case halves( like honda bond, yama bond, three bond case sealer) and you will be fine. dont forget to fill the waterpump cavity with two stroke oil and use two stroke oil for assembly lube.
If I do decide to pull the whole engine and split the cases, which I probably should, will I be able to replace the crank seals myself and do I need a flywheel puller to get the flywheel off. I really scared about tearing apart a perfectly running engine, but I know that it wont run forever and doing this should prolong its life. Are there any links with pictures out there of doing the bottom end. The pictures in the manual are black and white and really not that detailed.
I am just the kind of guy that goes over this kind of process in my head ten times before I acually do it, just dont like suprises.
I am just the kind of guy that goes over this kind of process in my head ten times before I acually do it, just dont like suprises.
You will need a puller for the flywheel. You can easily replace the outer crank seals once the crank is out.
Splitting cases
Unless the crank seal(s) have failed the crank is most likely good to go for another while longer IMHO. Our experience is the crank can go two or three top ends AS LONG AS NO OTHER ISSUE EXISTS.
Leaking grease on the back of the primary, top end pieces in the crank, severe overheating, detonation all negate the statement above. Doo cranks are pretty tough the way they come, unless something else happens.
Unless the crank seal(s) have failed the crank is most likely good to go for another while longer IMHO. Our experience is the crank can go two or three top ends AS LONG AS NO OTHER ISSUE EXISTS.
Leaking grease on the back of the primary, top end pieces in the crank, severe overheating, detonation all negate the statement above. Doo cranks are pretty tough the way they come, unless something else happens.
C
cjgodden
Well-known member
The flywheel can be pulled with a automotive style harmonic balancer puller. Lots of people have those and they work just fine. IMHO the bottom half is easier to take apart than the top half, If you can do the top, you can do the bottom, and the little extra time involved is worth the insurance. I was the service manager at a doo dealer and have seen MANY crank bearing failures between the 2500 and 4000 mile mark. there is no telling what shape the grease is in without taking it apart and looking. A bearing failure can cost you a whole motor, so a little time and some grease is CHEAP insurance.
