AtlasFBG2
New member
This is a 00 srx700 thats ported with Race Logic porting.Heads was shaved .010 and chambers redone to 17 degree angle.Has a Tempa Flow with 150,148.8,148.8 main jets.The cylinders was honed and new rings installed when ported.Maybe 200 miles on it since porting.Also had new base gasket and reed cage gaskets put on at same time.Pistons looked great when reassembled.Had 145 psi on all three cylinders.Need some advise on what burned down the pto piston.Do you think it was a coolant leak,pluged main jet,or a air leak somewhere?First two pictures are the pto cylinder,third pic is the center and fourth in the mag piston.Hows the wash look on the good pistons?
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Your mag side looks like its burning good. The wash looks good. Center cylinder looks a bit lean and your PTO looks like it was burning lean for sure. It could be a jetting issue or maybe a crank seal gone bad. I'd start by taking a look at your crank seals maybe.
YAMMIENEWBY
New member
Ask Mr Viper, guarantee he has some insight.............
600srxman
New member
the pto looks like its a wee bit rich and the mag side is a bit to lean put the center is really nice
looks like its been doing this for a little while
Center cylinder I think looks perfect, it has all the right stuff showing on it,mag side a tad only rich, but this can come from extended idling/low speed lugging. The pto looks like its been melting for a while now, not just all at once.
What I am about to say dont take the wrong way!!!, but the tempa-blow you have on caused this in my opinion from what I can see in the pics. Its been leaning the sled out after you have hot air under the hood. Like this scenario: You and your buddy's have been running fairly hard thru the trails, and suddenly you all come to a intersection, and naturally you stop to make sure everyone all catches up, you look at a map for a minute, Everyone takes off, including you, goose the sled up to 50-70mph, wham, the tempa blow leans out the mixture and until the airbox temp drops again, it continues to run lean.
This is a classis case, I have seen this many times before, (fixed many from this same problem)thats why there is carbon on top of the melted section on the pto piston. When you have a sudden problem it doesnt put dried carbon on the melted area and cover up whats been taking place over a span of time. just looking at the pics, looks like the carbon is on top of a drooping center crown to exh port edge.
With the mods you have the jetting would be very acceptable and should provide more then crisp performance.
Center cylinder I think looks perfect, it has all the right stuff showing on it,mag side a tad only rich, but this can come from extended idling/low speed lugging. The pto looks like its been melting for a while now, not just all at once.
What I am about to say dont take the wrong way!!!, but the tempa-blow you have on caused this in my opinion from what I can see in the pics. Its been leaning the sled out after you have hot air under the hood. Like this scenario: You and your buddy's have been running fairly hard thru the trails, and suddenly you all come to a intersection, and naturally you stop to make sure everyone all catches up, you look at a map for a minute, Everyone takes off, including you, goose the sled up to 50-70mph, wham, the tempa blow leans out the mixture and until the airbox temp drops again, it continues to run lean.
This is a classis case, I have seen this many times before, (fixed many from this same problem)thats why there is carbon on top of the melted section on the pto piston. When you have a sudden problem it doesnt put dried carbon on the melted area and cover up whats been taking place over a span of time. just looking at the pics, looks like the carbon is on top of a drooping center crown to exh port edge.
With the mods you have the jetting would be very acceptable and should provide more then crisp performance.
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