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Discussion Starter · #1 ·
Hi all,

Bought a used Skandic last year, 10K km on it. It was a great deal. Good Compression when I bought it (hes a mutual friend and airplane mechanic), and this season, it had trouble starting. On a lake the other day, and going 40km in 2nd...Stopped to shift to 1st, and it died. It would not idle. It wouldn't start for 10 minutes, then started again with throttle open. It would run as long as I gave it gas...then it died when I let of gas. It ran fine previously...so was kind of a sudden issue. Spark plugs, cables are good. Then Compression test....120 in first one, then 25 psi in second. I just ran the compression test without unplugging RAVE or anything...but Im guessing its time for a rebuild? Thought I would ask if there any other test or something I missed that my result in the low psi in the second cylinder. Worth checking for a leak? Im not super experienced with this, so thought I would ask before I park it for the winter and plan for a rebuild.

With that said, anyone have a good cost estimate for parts for the top end?

thanks in advance! Hope you are all having a great winter!
 

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Just yank the engine and pull the cylinders off. You'll know right away what happened. I've done several ETEC engines over the years and failures have mostly been caused by rotten intake boots sucking snow and lack of proper fuel and insufficient warmup time. Post some pics after you get it apart if you don't mind.
 
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Discussion Starter · #3 · (Edited by Moderator)
A few pictures attached...

Anyway, got it apart...and the piston was pretty messed up. looks like a ~2cm edge of the piston was broken off, and the top of the piston was full of melted debris. The top of the header? (not sure Im using right terminology) was pretty scarred up, as well as the cylinder. Plan is to replace the parts.

Anyone have an idea on how this might have happened? I warmed it up correctly, use 91 octane...so not really sure.

Anyone have good recommendations for pistons, cylinder, gaskets? Has anyone tried smoothing the cylinders? The other good cylinder is in good condition, good compression, will probably try to just smooth out some very minor scarring on it. Rubber intakes look good.

Also, is there typically an airfilter insert? There was nothing where the filter goes aside from the mesh on the body.
 

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Is the damaged piston scuffed on the exhaust side or kind of all the way around?
 
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That's pretty much what my riding buddies 600 did at around 1k miles. I attributed it to lack of warmup as it had some scuffing on most of the piston on the mag side. He also ran regular and not premium fuel.....when I rebuilt it I made sure to run the thickest base gasket that came in the gasket kit we bought. If I remember right, there were three different thicknesses and the thickest one will drop your compression ratio a smidgeon.
 
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Discussion Starter · #7 ·
That's pretty much what my riding buddies 600 did at around 1k miles. I attributed it to lack of warmup as it had some scuffing on most of the piston on the mag side. He also ran regular and not premium fuel.....when I rebuilt it I made sure to run the thickest base gasket that came in the gasket kit we bought. If I remember right, there were three different thicknesses and the thickest one will drop your compression ratio a smidgeon.
Thanks, @Olypopper! Did you get the jugs for the rebuild new or nickelised (sp?)? Did you use OEM or after-market pistons and gasket set? If you don't mind me asking, which cylinders, pistons, gasket set did you go with? Any brands to stay away from or that you recommend?
 

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I used OEM pistons but the cylinders and gasket kit were from Darby's performance, a local independent shop here in Fairbanks. Their gasket kit is branded as their own but I'm pretty sure it's Cometic. I'm not sure who does their cylinder service but I just exchange them across the counter as they always have them in stock. Where are you at? What town?
 
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Discussion Starter · #9 ·
Im in Whitehorse. I can get OEM through the dealer here...buts its an older sled with lots of km, so trying to save some money...looking at ordering the SPI hyperdrive set. I would have to ship the cylinders to get them refurbished and save like 50 CAD per....so may just get new.
 

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Im in Whitehorse. I can get OEM through the dealer here...buts its an older sled with lots of km, so trying to save some money...looking at ordering the SPI hyperdrive set. I would have to ship the cylinders to get them refurbished and save like 50 CAD per....so may just get new.
I've also had very good luck with Wiseco pistons.....I'm not much on the chinese knock-offs.............whats the exchange rate at the moment? It might be worth a call to Darby's here since they stock all this stuff. Depending on Canada post, you could have all your goodies by next weekend and have her back together!
 
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MCB also usually has the pistons and cylinders in stock and are cheaper than OEM. They have their own labeled pistons which I am running in two different engines without issue.

Sent from my iPhone using Tapatalk
 
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