top end rebuild question???

[m7162]

I hear when you rebuild a rev 600 motor you have to get all the trapped air out of the coolent lines, how do you do this and do i need to put some oil in the gas tank for break in?? and how much thanks got it all together and started in one pull and sounds great just dont want this to happen again any info would be great thanks mike

 

[2SMOKE]

What we have done in the past is start it up so it can cycle the coolant, lift the rear end for 30 seconds or so, then do the same for the front.

Also, on the 600's I think the front 2 head bolts above the rave valves are slightly shorter than the rest. Found this out when we rebuilt BLONDZ motor. If you mix em up the head could leak coolant.

On a fresh top end I would definately dump a little oil in the tank for an added measure. A cup of oil should be fine.

Hope this helps.

 

[snow_freak]

same as said above but also when you lift the front end (or just park it on a slope) take the coolant cap off and keep topping it off as the coolant will lower if any air is trapped. and i do all this with the t-stat out to avoid any second thoughts.

 

[AKSNOWRIDER]

the most effective way I have found to bleed the cooling system is to fire the sled up and pull the sled over on its side(the side that the coolant bottle is on first, coolant bottle on the low side), hold it on its side with the engine revved up just almost to the point of turning the track for about 15 -20 seconds..let it down level and repeat on the other side with coolant bottle now on the high side..and repeat revving the engine up for about 15-20 seconds..then let it back down on the ski's and check coolant level and check for warm hose coming from the back to the bottle..normally it gets all the air out in one time..sometimes you need to do it 2-3 times..but it always works....

 

[ak49er]

When i rebuilt my REV 800, I did a few heat cycle's with the nose as high in the air as I could get it, parking it up on a steep snowbank. As far as break-in, I used Ski-Doo mineral Oil, in the tank and resovoir, and also wired the oil pump Wide Open and made a few runs back and forth across the lake, about a 1/4 mile at a time, progressively pulling harder and harder.

I did alot of reading on how to break in motors; two and four stroke, sleds, boats, watercraft, and other motor sports engine. There were two schools of though, run 'em easy and gentle at first, and the second was break it in like you run it.

First thought being, go easy and let everything heat up the same and be real easy on the rings.

Second school of thought is to once again let everything come up to temperature slowly, and then run it hard to pressurize the cylinders, which forces the rings out of their shape and makes them conform to the actual shape of the cylinders, making a better seal.

Anyhow, I ran mine hard, with the oil pump tied open, for about an hour, and then trail broke it like any other OEM recommendations. I never did check compression before and after break in, but it still pulls strong today. 1000 miles later.

Good Luck.

 

[AK800RMK151]

the most effective way I have found to bleed the cooling system is to fire the sled up and pull the sled over on its side(the side that the coolant bottle is on first, coolant bottle on the low side), hold it on its side with the engine revved up just almost to the point of turning the track for about 15 -20 seconds..let it down level and repeat on the other side with coolant bottle now on the high side..and repeat revving the engine up for about 15-20 seconds..then let it back down on the ski's and check coolant level and check for warm hose coming from the back to the bottle..normally it gets all the air out in one time..sometimes you need to do it 2-3 times..but it always works....

Kinda funny...this is exactly as I was tought! It wroks like a charm!

As far a break in goes adding a little oil to the gas is just a good precaution. I laso wired my oil pump wide open for a few miles then backed it off. Ive got just over 800 miles on my rebuild and all is good....

 

[DVarmit]

the most effective way I have found to bleed the cooling system is to fire the sled up and pull the sled over on its side(the side that the coolant bottle is on first, coolant bottle on the low side), hold it on its side with the engine revved up just almost to the point of turning the track for about 15 -20 seconds..let it down level and repeat on the other side with coolant bottle now on the high side..and repeat revving the engine up for about 15-20 seconds..then let it back down on the ski's and check coolant level and check for warm hose coming from the back to the bottle..normally it gets all the air out in one time..sometimes you need to do it 2-3 times..but it always works....

X2 on that one.. worked for me several times after trying other ways of doing it... The only thing I did in addition was to pull the front end up on a somewhat steep snow bank with the cap off in addition to the side to side..