Ol' Grand dad was right

[magnumforce]

When he said, young feller, when you get into the nasty 3T habit, it's gonna cost ya $$$$$, ol' grandpa, he's still right!! ;D ;)Listen to, and respect your elders

After the GPS run , BTW it run 113.2 mph with my niece driving.

Before the mishap...

[wigman25]

The first pic, I thought it was a Rupp - Then I saw the second pic and realized it was only a Cat!

Had my heart pounding there for a minute!! Seriously, those triples go like hell but they are finicky - what happened?? Looks like a ring caught the exhaust port, ring gap problem maybe? Sorry to see your sled had a meltdown, I know how bad you must feel. Been there done that more times than I would like to admit. Good luck with figuring it out Cory. Wig

[magnumforce]

Hi Wig, Thanks! this is the beast that exploded the motor before a while back, I got a cheap drop in from Brown's (sucker for punishment I am) I don't know what happened, I went to Arctic Chat and there were about 20 older posts with guys having the same troubles on the 800's , I think there's a bent rod in this one. The guy I got it from raced it and never had much trouble but then again he didn't run it long. It'll have to sit now I'm scared to drive this thing anymore.

[rog929]

that sucks. I ran these for years with no problems. I put 3500 miles on a hooper 1050 and sold it to a buddy that still runs it.. run 131 everytime on radar. Throw those cylinders out and buy a set of 1050's. I used to run it on the ice and my shoulders would get tired. Another good set up is 1000 cylinders on an 800 with a base shim.. about 180hp with stock pipes. I love the tripples, Cat has the small block chevy of snowmobiling. I cant get my 900 ZR to go nearly as good but it did run 120 last weekend.

[wigman25]

I have heard a lot of those Cat 800's had some dependability problems, although they were screamers when they ran right. Looking at your pic, it looks like a mechanical failure and not a heat problem. Whatever it was, looks like that piston came to a screeching halt pretty quick! Usually involves a rod that now looks like spaghetti. One thought - any detonation? Sometimes that can kick a piston of a little and catch a ring on a port - usually cracks the skirts at the same time. I think if I were you I would follow rog's suggestion - go BIG. Put some big cylinders on that thing and make it really cook. Something about the stock 800 that had the problems, maybe a new top end would do the trick. It does get frustrating, that's for sure. Wig

[magnumforce]

Thanks guys, well I think I found out why? I took the head off and the o ring was out of place and was blown out of it's groove, it was way bigger than the groove itself, and I always had to add a bit of coolant all the time, checked the head with a straight edge WOW it's warped BAD, now I know the T-Cats live and maybe the coolant has played a part in this.
I would have showed a Rupp motor but they seem to stay together ;D

[2manyhobbys]

Here's a tip I got from a guy who has run ZRT 800 and T-cat engines in a mini-rod for pulling...apparantly these engines are notorious for twisted crankshafts. The cranks are pressed together and one of the throws slips and gets out of time. If its off very slightly the engine will be lazy/lack full power...if worse it can cause severe detonation/piston/crankcase damage. This was also a common problem on mid to late 90's Polaris XLT 597cc engines. A knowlegeable engine builder will know the correct crank timing/degrees of separation between cylinders and it can be checked using a dial indicator set-up without disassembling the engine. And your Grand dad was right...it can cost big $$$$ to repair. But nothing sounds like a triple!

[wigman25]

Cory: Thinking more about it - a combination of what 2many talked about, the cylinder sucked in some coolant and did a hydrostatic lock in that cyl at high rpm. Bent rod, totally blown out head gasket, broken rings, typical damage for that. Crank might be toast as well, they do bend sometimes. Gonna rebuild it with the big cylinders?? I would be very tempted, but it takes a pocket full of $$$$$ to do it! Wig

[magnumforce]

Thanks guys for the info and tips! it looks like you said Wig, sort of like a hydrostatic lock episode, I pulled it all apart, got Parkland to check the crank and rods, all looks good, stuck a used cyl and piston I had and got the orig. head. It's holding so far and didn't have to add any coolant yet, grandpa isn't with us anymore but his philosophy still is ;D I had a 580 a few years ago and I took it aparts and both O rings were blown out and the heads were warped? here's a couple pics, sorry for the shameless promotion of this Cat but ahhh it makes for some reading material ;D the bottom pic of the head is hard to see but I just ran a straight edge and the top left didn't even touch, the ring beat up the chamber pretty bad and the piston almost split in half Ha ha ha, a big bore would be nice as I like toying with this

[wigman25]

That head looks like you had some jewelry bouncing around in there for awhile! Looks like you sucked some water in there - look at that ultra-clean spot on the top of the piston, it appears to start right where that gasket is out of the slot, steam cleaned pretty nicely. When you do it, you sure do it right! Good luck with the new piston/jug. Take it easy, now, you're not riding a Rupp! Wig

[RuppParts]

See what happens when Rupp riders jump ship to 1 of the other brands? Cory and Wigman know first hand!

[Ruppsforever]

Brandt you might be right..... I jumped ship and bought a polaris and my hood busted off.

[magnumforce]

Brandt's right! bad things happen just like a voodoo curse I think everyone owns or did own a Christine at one time
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