How do these plugs look?

[sledneck_03]

Remind me not to tag along with you in the mountains.. LOL

Today's sleds, or at least within the last 10 years are pushed harder for HP, thus shorter life.

But then again, you must just ride the flats?

allllright!!!! you win im pulling the damn pistons. at least going to inspect the stock ones and do new gaskets and rings. if the pistons look bad ill put new ones in. I guess it will sell better too if i refresh the top end and put some miles on it for the rest of the year.

Spx piston kits are $120 a side and $62 for a top end gasket kit.

 

[sledneck_03]

Did you do this plug check at WOT , hit the kill botton , with the throttle still wide open !!

top ones were done like that. but the bottoms were just riding. Ive been told to check my oil injection, looks oil rich.

Grabbing a new filter today.

 

[CUSO]

They may look perfect, don't be fooled by that though. Metal fatigue rears it's ugly head without any signs. Seen it way too many times.

Just sayin' LOL

allllright!!!! you win im pulling the damn pistons. at least going to inspect the stock ones and do new gaskets and rings. if the pistons look bad ill put new ones in. I guess it will sell better too if i refresh the top end and put some miles on it for the rest of the year.

Spx piston kits are $120 a side and $62 for a top end gasket kit.

 

[Modman]

Bottom plugs are rich by most standards, tops look worse. flat face on the bottom of the threads should be the colour of the jetting you want, to get a really good jetting reading you need to look at where the deposit ring occurs on the porcelain around the center electrode, most times you will have to cut the threads off carefully to see it clearly. ground strap colour and colour change location are timing and plug heat range.

The side to side motion of the connecting rod is what causes pistons and cylinders to come out of shape, wear and then eventually fail. As cuso mentioned, pistons may look good but it can be a misleading visual just by looking. Have cylinders checked or check them for oval wear when you pull the pistons. I wouldn't monkey with your oil pump setting unless you are using excessive oil. Oil protects your motor internals from wear by being the sacrificial barrier, and it sounds like you've had good luck with lots of miles on your sleds, I wouldn't change the pump settings or the type of oil you are feeding them. A little bit more oil is better than not enough. Stick with what is working and hopefully you will enjoy many more miles.

Hope that helps.

 

[sledneck_03]

Wholly hell polaris pistons are $200 a side! And $80 for the gasket kit.

$500 phuk that, spx pistons it will be for $300.

I work at a engineering/ inspection firm.

If they were steel I could get them mag particle inspected for free! Haha and visual inspected.

 

[ferniesnow]

I'm with CUSO on this one. The chart says it all and that is a nice touch!

Top end is easy compared to a short block. Good luck.

 

[Modman]

Wholly hell polaris pistons are $200 a side! And $80 for the gasket kit.

$500 phuk that, spx pistons it will be for $300.

I work at a engineering/ inspection firm.

If they were steel I could get them mag particle inspected for free! Haha and visual inspected.

Not sure on the SPX but the stock Polaris pistons will likely be cast, they are a little more dimensionally stable and the expansion co-efficient is less on cast than forged, because the forged pistons are denser. Cast use a higher silicon, why they cost more, a little more brittle than forged pistons but expand very uniformly and not as much as forged, good for longevity where joe public is WFO at dead cold from the parking lot. If the SPX are forged then you just need to make sure you warm them up, as they will take a little longer to expand/heat up and become uniform. Forged pistons are tougher in the long run, after a few dozen heat cycles to a high temp the molecular structure will settle and they will become more stable (this is what I was told by an engine builder, I've never actually measured this difference myself personally). Forged pistons will expand faster than the bore, so no WFO from the parking lot or you will increase your chance of seizing.

The clearance for install might be a little more as well as the forged pistons will expand more, so take that into account when you are installing them, make sure to get the right clearance. as I mentioned - warm them up well and don't take off dead cold at WFO and they will be fine. Warming them up and getting the right clearances can't be stressed enough. This was an issue with guys installing Wiseco's or other forged pistons, guys not installing them with the proper clearance or taking off dead cold and then seizing. If the SPX are cast then its still a great idea to always warm them up, but probably will need a difference clearance value similar to OEMs.

I don't know what the pin seats are like but there was talk that some of the aftermarket pistons for sleds had wrist pin bosses that were recessed and this was allowing short circuting of the exhaust and intake ports. Also weight of the pistons, forged have been known to be heavier and lighter than stockers. Compare the old pistons to the new pistons, looking for subtle differences like this when you get them. Make sure the bores are correct and round, clearances are good (sidewall and deck/head) and don't just toss in new pistons.

 

[moyiesledhead]

SPX are cast and I've had very good luck with them in both Poo and AC 700's. My M1000 not so much though. Not sure why??? Like Modman says...measure, measure, measure. I've actually started just replacing the jugs too when I do the pistons. They're only $299 exchange and you end up with an all new top end.

 

[duck]

i would say plugs are a little dark/rich. But not enough to drop your rpm. I would check the clutches for wear. Also how old are clutch springs.

I would have thought clutching.....maybe even the weights and pins for wear. But, most likely a mapping thing.....

 

[Slamnek]

That sled should be run on regular fuel also. My brothers 06 M7 runs like crap on premium.

 

[kenvb]

I have sold and installed hundreds of SPX and Wiseco pistons, less trouble with SPX ones, have 6900 Miles on my 92 500 EFI ,, had another 92 10 yrs ago with over 20,000. on original motor. why dont these new sleds last that long?

 

[CUSO]

Because your 21 year old motors didn't put out 140hp?


That's what I'm figuring.

I have sold and installed hundreds of SPX and Wiseco pistons, less trouble with SPX ones, have 6900 Miles on my 92 500 EFI ,, had another 92 10 yrs ago with over 20,000. on original motor. why dont these new sleds last that long?

 

[KatMan]

Because your 21 year old motors didn't put out 140hp?


That's what I'm figuring.

doesnt explain why you cant hold a motor in a polaris

 

[CUSO]

I was explaining about the 700. It is probably one of their most reliable motors ever.

doesnt explain why you cant hold a motor in a polaris

 

[sledneck_03]

Figured out my fuel filter is original. 4500 miles on that too. Changed it and will see how it goes, hope that was the issue this whole time and why I've lost 100 rpm each year since 09. Stupid!

 

[sledneck_03]

What I found out was I talked to my dad, he's been in the Dominican for two weeks. Discussed my issues he said that back in 09 when I thought we changed the filter I bought a 900 one that is too short so we blew it out with a compressor and re installed it.

I cut it open and it's paper inside. He said we thought it was a screen.

 

[retiredpop]

Figured out my fuel filter is original. 4500 miles on that too. Changed it and will see how it goes, hope that was the issue this whole time and why I've lost 100 rpm each year since 09. Stupid!

All I can say is that you must have been running really clean fuel. First change is recommended after 1000 miles and then every 2000 after that. I think they are a 10 micron filter which is pretty darn small.

 

[sledneck_03]

All I can say is that you must have been running really clean fuel. First change is recommended after 1000 miles and then every 2000 after that. I think they are a 10 micron filter which is pretty darn small.

This is the inside of the filter. Darker side was outside. I suspect the paper is yellow new like the inside clean corners