Well, this is the piston from a 98 SRX I sold a buddy of mine last year. Looks like detonation to me but I'm not sure. It happened on a very cold day. What do you guys think. He's rebuilding this cylinder but I'd hate to see it happen again. I don know he did not have his carb heaters on.
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bluemonster1
LIFE MEMBER ONLY ONCE!!!
don't know what is happening,but this season there seems to be a lot of guys having engine problems with there SRX's and even Vipers going down.
Looks like a lean melt down to me.
9801srx
Member
me to. what do the other ones look like? if they are ok it was probably a frozen or pluged main jet ,or an air leak.YamerDown said:
bluwulff9
New member
Could it be new additives in fuel
wowwwwwwwwwwwwwww i'm not the only one that melt piston that way wooohooo
does it run stock heads ???
hey turk it remind me my 3 piston i melt last yearTurk said:
valin
Active member
Holy detonation. I too would say octane related. What fuel were you running?
ottawaair
New member
definately a lean problem, just did my top end 2 weeks ago, looked the same on pto & mag. My jets were leaner than stock-long story- & it got cold that night. yea definately lean.
He was running premium fuel, 91 octane I think and his heads are stock. I'm going to get him to check his other pistons to see if they look lean or not. I thought a lean condition normally caused the piston to score or melt along the rings and skirt on the exhaust side and detonation looked more like this. Not sure though.
Is there any connection between a lean condition and detonation?
staggs65
Moderator
lot of sleds burning up in maine this year, everyone saying to run k 100 mg do to the fuel, this happening in other places?
9801srx
Member
yes there is.when the mixture gets to lean the combustion temps go way up in the cylinder which causes your normally good octane level to be not high enuf to prevent deto.i have destroyed lots of pistons the exact same way yours looks from being to lean for the temps outside .i have also destroyed a couple from low octane fuel but they usually look sand blasted all the way around the outer edge of the piston and had the ring land between the two rings broken away in places but the exhaust edge was not burned away like the one in your picturejaydaniels said:
well i solved mind with bigger jet ...............
Adding fuel to correct a detonation problem is like duct taping a flash light to a burnt out light bulb. It just covers up the underlying problem.
To correct the problem properly you should run a higher octane fuel or lower your compression ratio.
Have you shaved your heads or removed a layer of head gasket?
To correct the problem properly you should run a higher octane fuel or lower your compression ratio.
Have you shaved your heads or removed a layer of head gasket?
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horkn
New member
9801srx said:
me 3....
motodave289
Member
YamerDown said:
There is no headgasket to remove layers from, has orings.
motodave289
Member
9801srx sounds like he's right on the money to me. I would pressure test this thing after it's put together to check for air leaks, after checking out carbs.