750 triple L/C sled engine

[Kaptain Krunch]

Well long story short, i got a 93' polaris storm for free, engine is seized from sitting, has everything except seat, hood, track, and skis. The primary and secondary and disk brake/caliper is there so thats good. The engine is supposedly rated at 140 hp at the crank , and its gonna be in my kart soon. So anyways i have a few problems, figured maybe someone could help. First off the side of the primary clutch (side that outside side, one that moves) has 3 hairline cracks in it, the guy told me he had used it in his other sled like that and it would be fine, im no so sure though? I have a primary from a 440, if it fits (no idea if it will) would it work? or is a 750 just too much power for a 440 clutch? Lastly, i have no idea how powerful sled water pumps are but would they have enough power to push the coolant through a car radiator fast enough to keep the engine cool? The radiators on the sled are pretty wimpy, and look like heat sinks and have no fans too cool them (i guess snow is supposed to splash up and cool them off).

 

[Kaptain Krunch]

Heres a pick of the engine, this isnt mine but it looks the same but in much better condition.

the pipes are gonna be hard to pack into a kart...

 

[theo]

See if the 440 clutch takes the same belt width. I would throw away the 750 clutch away, I would not want that to grenade on me.
A small car or maybe a large bike rad will work if out in the slip stream and keep it up, hot water rises.

theo

 

[kibble]

First off the side of the primary clutch (side that outside side, one that moves) has 3 hairline cracks in it, the guy told me he had used it in his other sled like that and it would be fine, im no so sure though?

Eh.... I'd be worried about that one, especially if it was rotating fairly fast. I don't know much about sled engines though to tell you if the other one you have would work.

 

[Kaptain Krunch]

Yea i would be scared to have a piece of steal rip apart at 8000+ rpms...I'll have to see if the 440 clutch will fit, its also from a skidoo not a polaris so im not sure. I'm also getting another 440 sled (getting a collection now) that might have the primary, and that is a polaris indy trail so that might work.

I guess if worst comes to worst i can just make a nice strong guard around it, so if it does grenade i'll be safe.

 

[kibble]

I'm also getting another 440 sled (getting a collection now)

I hate you..... :arf:

 

[Kaptain Krunch]

I hate you..... :arf:

Its seized also, and im paying $10 for it haha. I've been searching for rings for this 750, the best i can find is a piston and ring kit, OEM off a local warehouse for $350...anyone know where i can get just a set of rings, the pistons look fine through the exhaust ports.

 

[Kaptain Krunch]

Well yesterday i put my 5.5 back on the kart until i get this engine running, and realized how bad of an idea putting a 140hp engine in a yard kart is...my 5.5 will push me (180 lbs) 30mps+ really easily with a crappy clutch, imagine what this triple will do...Anyways, that hasnt stopped me i will most likely use it if it'll run right, if not i can part it out and make some cash, the heads go for $25 each so right there $75 profit, plus all the electronics could probably make me another 150. Anyways, does anyone know how to check to see if the oil injector is working, its different than the ones i've seen on sleds, the injector is right in the boot, the ones i've seen have had little oil injector pumps pump oil into the carb bowl where it mixes.

 

[crazycart]

Don't use a 440 clutch on a 750. It'll blow that thing to pieces. The storm engines weren't the most reliable, and they liked to blow up. Now, they are powerhouses. Way to much engine for a little kart like you have. Part the engine out.

 

[Kenny_McCormic]

Don't use a 440 clutch on a 750. It'll blow that thing to pieces. The storm engines weren't the most reliable, and they liked to blow up. Now, they are powerhouses. Way to much engine for a little kart like you have. Part the engine out.

You're no fun! This is America, you should be able to kill yourself however you please.

 

[kibble]

my 5.5 will push me (180 lbs) 30mps+ really easily with a crappy clutch

30 Miles per second?!?!?!?!

 

[Kaptain Krunch]

Yes, miles per second, its because i have chrome rims, they make me go faster

Anyways i just went out there, i freed up the engine a little, it is still hard to turn over, i took off the heads and the cylinders aren't bad, a little surface rust that should just hone out. one piston is slightly scored and has what looks like a dent in it but the jug isnt scored? no idea how that happened, the head is also fine so the dent is supposed to be there i guess?

Crazykart, i realize its got a lot of power...and is probably overkill to the extreme, but i may use it i have no clue, it depends what other engines come my way between now and the time i hone out the cylinders and get ready to buy rings/gaskets. from what i hear the rings for this engine are $25 a piece, so it would cost me $150 just for the rings, so i have to be serious about this if im gonna spend $150 + $80 for a gasket set and crank bearings on top of that.

 

[crazycart]

Take into consideration all the time and money it will be to use this engine. Don't get me wrong, it would be awesome, but it needs a lot of work. Your crank may also be bad, another common problem with the 750's. You need to make mounts, jackshafts, find a axle that will handle the power($$$) Rejet all 3 carbs for warm weather use, i'm just saying it will take some money and work. Goodluck, post up some pics!

 

[Kaptain Krunch]

Yea i was actually just thinking about it and its most likely not worth my time. Is there any way i could fix the clutch it came with, theres 3 cracks that dont go all the way up and down, but there like right where the belt would first hit once the engine starts revving. either way, i got this sled in a deal where i made a $25 outright profit plus any parts i can sell off this sled, and im sure i could make a decent amount.

 

[Kenny_McCormic]

I would keep it and use it as a sled.

 

[theo]

Get a twin cyl, with 1 carb, lots of power and less fuss setting it up. As for the cracked clutch, would you run a engine with a cracked flywheel?

theo

 

[Kaptain Krunch]

I probably would use it as a sled if it had a seat/gas tank/track/ skis...i have a feeling parting it out is the way to go, im sure just the pipes could get me alot.

Theo, i would run a engine with a crack in the flywheel...if i didnt have to be around it while it ran. but i get your point.

 

[Kaptain Krunch]

Well i just went out there, one of the cylinders is fubar. I put the to side pistons to almost TDC and filled with oil, the one on the right is full of oil, the one on the left drained through, you can see the jug is warped or maybe its the piston either way theres a decent size gap.

 

[Jerryburger]

Kaptain Krunch..... with all these these sleds/motors falling from the sky around you.... I hate you! (Kidding)
At the very least, keep the shafts/clutches/parts... they're always handy for something...
What's the sled with the twin that you're going to get? That sounds a little bit better suited for karting.

 

[Kaptain Krunch]

Yea the one with the twin is just for parts, its been sitting outside without a hood or the heads on it for a few years, it was a polaris indy tho.

But speaking of this thing, i was out there today i got it fairly freed up, but i think the crank bearings are rusted... anyways i only have 1 sparkplug cap so i put the heads back on and tightened them a little, poured a little gas mix in one of the cylinders and pull it and the mother ****er kicked over! it scared the **** outa me, then i pulled it again and it popped then cought the engine bay where i spilt some gas on fire...but i put it out without damage.

Anyways, i'm going to part it out i've started to strip parts off. Any tips on getting the flywheel off? I made a makeshift puller out of some 1/4" flatstock and it will not pop off, i bent the stock but the flywheel just wont pop off...