Out for this season..sigh...

Yea... I examined everything before taking off for a ride... carb boots, exhaust leaks, airbox.... I did a complete check up before taking a ride on it....


I made sure I read up and did everything that should of been done unless I missed something but I dont think i did....

Could there be a leak in a gasket or something somewhere that can cause that?
 
IMO:
This definately looks like Detonation damage from either,low octane fuel, lean jetting, air leak, too high of compression, advanced ignition timing, or a combination of all or some of these issues.
Since you picked this sled up used...you need to check the cylinder head ccs. The 2000 - 2002 SRXs are as tight as you want to be for a trail sled.
Ensure there is no timing advance key or race CDI installed on this sled as well.

JM.02c
 
Mrvipe did the porting and did a "trial/pump gas" safe port and polish... while i was getting 94octane through a busy gas station near a highway... (however the fuel does contain ethanol)

I cleared everything with bendersrx while doing maintenance making sure there where no other add ons/mods that I would need to be aware of.

How would I check the CC on the heads? I got another set here that are port and polished as well and dont know the cc...

The only thing im leaning towards is poor fuel... but even then...I was running 94
 
If MRVIPER set this up for trail/riding it should be OK for premium fuel.
For info on fuel + the cylinder heads do a search on "SRX head clearance"...MRVIPER has a good write up under that post.
Looking at your jetting specs[148.8 148.8 151.1] I would suggest thats too lean for todays "E" fuel and questionable octane. Most guys are running Ported SRXs more like 152.5s to as high as 157.5s

JM.02c
 
im just wondering if it isnt that the fuel is still burning when it gets to the exhaust port like late spark? there has been a few of these that look like there jetted ok even rich and theres no apperence any where else of detination on the piston? now this one the eroded area is not silver its black its been there for awhile, i wonder if it was ran hot or lean at one time?
 
Ill check on the write up mrviper did...

Yea I noticed alot of people are running higher jetting specs...

Wouldn't I have seen damage in all 3 cylinders/pistons? the one that has no damage so far is the middle cylinder/piston and the one with most damage is the exhaust side and has a higher jetting then the other 2... thats what gets me wondering... if its really poor fuel...

no1chevy... that can be possible... but there is also a chance I was riding it for a while...while this was happening...
 
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When a sled is jetted for max power, the Exhaust gas temp is running close to the edge...in other words it doesn't take much to cross the line into the temp range where engine damage starts to occur. Each cylinder is never goig to reach that point at the same time unless they are all running at exactly the same temp. The fact that you have damage on more then one cylinder means all cylinders were adversely effected by the same issue...again tends to lean to a jetting +/or fuel issue.
I would also ensure your carb needles are at least in the #3 clip position with both plastic washers underneath the clip or maybe even in the #4 clip position with both plastic washers under the clip...better too rich then too lean!
 
yea definately... Ill check out the carbs... and see what its at... and prob order some jets and bump the jets up and do some testing next season for jetting... guess im getting a head start on re vamping the srx...

according to the pics of the plugs.... they where decent?
 
kinda getting depressing... 2 srx's in 2 seasons... and the current one was maintained and inspected closely.. epecially after my first srx completely went on me... dont get why i cant get one to last me.... 700km's on it thats all for this season
 
those plugs are impossible to read with the pic quality.

was prem fuel used?

carbs clean,pilots?

just looks like detonation/air leak to me,bad pics,but thats ok.
 
yea sorry for the pics... Cant find the good cam... so had to use my bro's cheaper one...

prem fuel was used... carbs where cleaned... everything was cleaned piece by piece... and made sure there was a steady flow when cleanning.. as i was taking everything apart i was looking to see if there could of been a air leak somewhere but no dice... im out of ideas of what it could be besides carbs and fuel quality... though carbs is where i cleaned them very properly to prevent this...
 
If thats the jetting don told you to run for your temps and alt and no air leaks(seals?)dunno what else it could be but crap gas and detonation.

do many WOT pulls? did you check oulg color often?
 
from what bendersrx told.. the jetting was set up properly with dons advice... I did do alot of wot pulls at a lake... I checked plug colours 2 times at the lake...and the plugs poped up a decent coloured brownish black..
 
Ride.Race.Live said:
from what bendersrx told.. the jetting was set up properly with dons advice... I did do alot of wot pulls at a lake... I checked plug colours 2 times at the lake...and the plugs poped up a decent coloured brownish black..
Click to expand...

Smokey, soot, like black is lean...it can be very deceiving. Oily wet black is rich.
The only true + accurate way to do a plug read is with fresh plugs, WOT for at least 10-15sec then hit the kill switch with the throttle still open.
 
Yea... ill have to try that out when the engine is up and going... Hard to tell... right now... with the way the plugs are... i know modsrx and concept are not far from me if i do need some help with something if they are willing.... but yea...

What are some seals that I should check out? anything in the engine that could cause a air leak? and have this happen
 
ah ok... any way of checking them? or its something i pretty much just take out and replace? wether they are good or not

thanks for the help so far guys... just trying to pin point this problem so i dont run into it again!
 
yes because it;s a very important part,one leak and your motor will run lean and burn down. You can only replace it with crank out case split.
 
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