was riding today and while going through a feild at wot the sled lost power,
sounded like it was running on 2 cylinders. pulled over pulled out the plugs and the center one didnt look good
ill post pics below. the other two looked fine. replaced the plugs and fired it up for two seconds, didnt sound good so i shut it off right away and didnt start after that.
i havnt opened the engine yet but im pretty sure i melted the center piston.
jetting is stock as far as i know, needle is set at 3.25 and the plugs always looked perfect.
what do you think caused this?
sounded like it was running on 2 cylinders. pulled over pulled out the plugs and the center one didnt look good
ill post pics below. the other two looked fine. replaced the plugs and fired it up for two seconds, didnt sound good so i shut it off right away and didnt start after that.i havnt opened the engine yet but im pretty sure i melted the center piston.
jetting is stock as far as i know, needle is set at 3.25 and the plugs always looked perfect.
what do you think caused this?
Center plug
And the tow other plugs
And the tow other plugs
at wide open to lose a cylinder, possible something in the needle and seat in the carb, jet, something that had to block fuel flow as a guess, your other 2 plugs look good, even some safety in there on them.
91 gas or??
only way to know is to take it aprt, its ugly for sure with the plug looking like that with alum. on it. post some pics of the piston tops when you get head off.
91 gas or??
only way to know is to take it aprt, its ugly for sure with the plug looking like that with alum. on it. post some pics of the piston tops when you get head off.
turbotod
New member
Hope this helps
A few years ago my center cyl. went on me, upon further inspection I found that a pressed in fitting on the bottom of the crank case under the center cyl. had fallen out. So I traced the hose back and found it went to the oil pump. Man was I pissed.Just my luck when this happened not only did it starve the center cyl. of oil but also alowed air to get in thus it spit. The next engine I instaled I JB welded all three fittings on the bottom so it wouldnt happen again. Hope this helps and good luck.
A few years ago my center cyl. went on me, upon further inspection I found that a pressed in fitting on the bottom of the crank case under the center cyl. had fallen out. So I traced the hose back and found it went to the oil pump. Man was I pissed.Just my luck when this happened not only did it starve the center cyl. of oil but also alowed air to get in thus it spit. The next engine I instaled I JB welded all three fittings on the bottom so it wouldnt happen again. Hope this helps and good luck.
always use premium,
and have a bottle of octane boost in the back if i cant find premium
do you think the cylinder is shot?
and have a bottle of octane boost in the back if i cant find premium
do you think the cylinder is shot?
bluemonster1
LIFE MEMBER ONLY ONCE!!!
we need pics to see..
O2viper700 said:
likely....drain the coolant out, theres a drain bolt on the front of the waterpump cover( 10mm head), on the clutch side. it says drain on the cover and the bolt has a brass washer behind the head. Drain it out and pull the head. take pics and post
next, look at the airbox, is the carb seated in the airbox boot all the way? if so remove it, then pull the carb rack.....
Same thing happened to my srx 1 month ago. Same cylender and all. My middle carb was full of dirt. Lack of maintnance and it was melted bad
I tore into it today and this is what I found
Is this head still usable?
Is this head still usable?
The carb boots were all on very good, so I took the airbox and carb rack off I didn't take apart the carbs yet. There was gas in the airbox. Is that normal?
Last couple of times I took it apart there was gas in it I just thought it was normal.. Is it?
Also the coolant was low. I checked it about a month ago and it was perfect..
Would it have burned off that coolant when it burnt down?
This is sorta the level the coolant was at before I drained it
Last couple of times I took it apart there was gas in it I just thought it was normal.. Is it?
Also the coolant was low. I checked it about a month ago and it was perfect..
Would it have burned off that coolant when it burnt down?
This is sorta the level the coolant was at before I drained it
looks like you caught it in time and just need new piston/rings, i would lightly hone the cylinder to remove any material on walls.
head can be reused just take some emery cloth and smooth it out, it doesnt have to be silky smooth just not rough edges. It looks ugly but wont change the way it runs if you smooth it out.(nobody sees it after put back on...lol)
coolant was definitely low, could have been overheating it. The other 2 pistons do look a bit lean but not too bad, likely from the excessive heat. i can see the wash marks on all 4 corners which is good, so its likely the heat just showing it self.
I would pull the carbs apart and for sure pull the float pin on the center one,remove needle and seat, see if junk is in top of it. then check your jets in there.
head can be reused just take some emery cloth and smooth it out, it doesnt have to be silky smooth just not rough edges. It looks ugly but wont change the way it runs if you smooth it out.(nobody sees it after put back on...lol)
coolant was definitely low, could have been overheating it. The other 2 pistons do look a bit lean but not too bad, likely from the excessive heat. i can see the wash marks on all 4 corners which is good, so its likely the heat just showing it self.
I would pull the carbs apart and for sure pull the float pin on the center one,remove needle and seat, see if junk is in top of it. then check your jets in there.
I noticed the needle in the center carb isn't centered in the tube it goes into..
Would that of caused it?
Pics:
Throttle closed
Throttle open
Throttle closed
Throttle open
Would that of caused it?
Pics:
Throttle closed
Throttle open
Throttle closed
Throttle open
no, thats ok, that wouldnt have cause it. Remove the float pin and then the small phillips head screw, pull out the needle/seat and see whats on top of it.
mrviper700 said:
Ok will do.
Looking at these pics I think I have to flush the bottom end there are pieces of aluminum
Do I have to split it or can I pull the engine and flush it out with mixed gas?
yours actually was pretty minor, I would just for good measure take some old mixed gas or kerosene and flush it out, just pour a little but in there and work the crank around to stir it up if any debris. I use a little air powered suction hose to remove it then compressed air to blow it out. If you dont have the suction tool, you can get a cheap manual fluid transfer tool at harbor freights, it looks like a grease gun with a hose on it, pull the handle it and removes the old fluch fluid. When your done dribble a bit of 2 stroke oil in the 2 holes in the case, and some on lower rod bearing to lube the crank bearings. Reinstall new pistons/rings and so forth.
BTW_ grab as much as you can with tweezers or long needle nose pliers first, no sense in washing anything big into the bottomend.
BTW_ grab as much as you can with tweezers or long needle nose pliers first, no sense in washing anything big into the bottomend.
The first pic of the bowl appears to show some kind of burr/sprue where the seat o-ring meets the seat bore. Perhaps big enough to restrict flow through the seat orifice and also too big to get through the top hat screen. Did it perhaps drop out of the seat when you removed the needle valve?
Looking again - is it machining to the seat to accomodate the hold down screw?
Hard to see the out of focus top-hat screen but it appears to show some signs of debris but not plugged.
Aside from the top hat screens, nice, clear pics.
Looking again - is it machining to the seat to accomodate the hold down screw?
Hard to see the out of focus top-hat screen but it appears to show some signs of debris but not plugged.
Aside from the top hat screens, nice, clear pics.
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now gently blow into the metal fuel line nipple for that cylinder,carb and see if any junk comes out where the seat was, sometimes it is in the tube/nipple and carb area.
Also, I would pull all of the seats to make sure it doesnt happen again in another cylinder since your right there anyways.
I forgot to ask since the beginning of your thread, did you just get gas before this?? or had you been riding on this tank of fuel for awhile before it went down?
Also, I would pull all of the seats to make sure it doesnt happen again in another cylinder since your right there anyways.
I forgot to ask since the beginning of your thread, did you just get gas before this?? or had you been riding on this tank of fuel for awhile before it went down?
mrviper700 said:
I actually just fueled up like 5-10 minutes before it burned down.
I filled up for 38 liters. Filled up with 91, but somtimes I wonder how fresh the premium gas is..