SRX 600 Jetting/Plug Wash
- Thread starter bADa$$ SRX
- Start date
bADa$$ SRX
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super1c
Super Moderator
Those plugs are right on with little room for cold temps with the mods to air box as you found out. Ouch. That sucks.
shaggyzr2
Active member
Was that one carb maybe a little dirty and running lean?
Vincent
New member
That Sucks.
mod-it
Member
That sucks, sorry to hear what happened.
When first looking at your first post I was going to comment that they are leaner than I would feel comfortable with. Right on the edge with zero room for a lower altitude or colder temps.
When first looking at your first post I was going to comment that they are leaner than I would feel comfortable with. Right on the edge with zero room for a lower altitude or colder temps.
bADa$$ SRX
New member
Going to pull the carbs apart again, looks like the center was a little leaner than the others, new jug and piston on the way
A couple of bucks
VIP Member
Top hats full of snot?
all 3 cylinders are lean, dry as a desert. its not only the plugs but looking at the piston tops as well to guide you on jetting a sled. I have a tech article with pictures on plugs and pistons tops to guide you. As for going off your first pic, see how the center electrode is silver all the way across, that's right on the edge for that exact temp with no room for temp drop, so that day was too lean for trail riding in my opinion, that would be race jetting for a short drag. You also have to watch using modified airboxs, it certainly will change the jetting. Do you have a bender cold air intake on the hood as well?
bADa$$ SRX
New member
Long story short there was six 3/8 holes drilled in the bottom of my air box from the day I bought it. Rode in -10 degree weather never had a problem. I’ve put over 6000 miles on the sled and it never missed a beat. This year mice chewed threw my air box and expanded one of the 3/8 holes to maybe 3/4 of an inch. Siphoned the old gas out. Went through and cleaned the carbs and patched all the holes in the box. Sled would bog on WOT after it warmed up and would backfire. Found a broken powervalve cable. Put a new cable in, cleaned all 3 valves and adjust to spec. Same thing, would still bog on WOT after it was warm, temps were around 30 on these days. Took carbs back out and cleaned again but didn’t pull the screens out because i couldn’t get the float pins out. Put carbs back in and ripped around the yard with no air box, ran like a top, so I figured it was running rich. I put the air box back in, took off my patches on the holes and took the cylinder dividers out to compensate for the larger hole from the mice on the mag side cyl. Sled ran really good and that’s when I took the pics of the plugs. Put gas in and went out for a ride. Trails were like glass so I was running almost WOT across all the fields. I stopped a couple times and checked the plugs, looked a little darker than the pic I posted. Went about 25 miles and was on a very long WOT pull and that’s when I lost the cylinder. I agree the pistons all look lean but it may be a little deceiving because I always squirt trans fluid in the cylinders when I summerize it to remove the carbon from the power valves and this happened after only about 40 miles on the year. New jug and piston are on the way. Step one is to go through the carbs again. Any thoughts on the airbox? Thinking I want to patch some of the holes again. I do not have a cold air kit. How much gas should come out of the fuel pump when pulled over? Mine just seems to barely dribble.... Thanks guys
Last edited:
Vincent
New member
Personally I wouldn't run your sled with a gutted air box. Heard and seen to many blow up stories associated with such mods. This story just adds to an already long list of engine failures
bADa$$ SRX
New member
What’s the best way to patch an airbox? Three of the holes are drilled on the curved part right under the entrance to the carb. I used gorilla tape before but thinking the residual gas will eat the adhesive away over time, can’t seem to find a used one for under $75.
Have you checked Facebook market place? I know there are a few sleds that are getting parted out in the west Michigan area. Also have you checked some of the salvage yards in Michigan?
find a used airbox bottom. the dividers wont make any jetting difference as long as the center shelf remains stock with the 3 factory holes, as soon as that it modded or removed or more air is added via cold air top, holes drilled in shelf, or in your case airbox bottom it leans it out instantly. The piston tops are bone dry, that why I say its lean on all 3, more of a dull sand blast appearance, if rich enough.. they will be smoke colored even if new, but shiny from the gas/oil film. I understand the trans oil thing but it didn't obstruct what the evidence is visually.
Another thing is the gas quality anymore, its not optimum for a 2 stroke engine by any means, the ethanol just leans it out more because its taking place of the gas and you need more of it to equal gas, so you need bigger jets to equal what gas used to be. use the highest octane fuel you can find and use octane booster. Just keep a bottle in the trunk and dump some in every fill up, cheap insurance when your on the edge! It cant take 91 and make it 93 by any means. Always best to jet it up rich and then back down some, if in final set up your a 1 jet bigger then optimum shows you on plug and piston tops, will show you zero difference felt in performance on a srx, they actually like a lot of fuel to tractor its way up thru power curve. Get yourself a little flexible bend a light, they have them at hardware stores and like menards, etc. you can look at piston tops and the plugs, theres a lot of information the engine will tell you if you look.
Another thing is the gas quality anymore, its not optimum for a 2 stroke engine by any means, the ethanol just leans it out more because its taking place of the gas and you need more of it to equal gas, so you need bigger jets to equal what gas used to be. use the highest octane fuel you can find and use octane booster. Just keep a bottle in the trunk and dump some in every fill up, cheap insurance when your on the edge! It cant take 91 and make it 93 by any means. Always best to jet it up rich and then back down some, if in final set up your a 1 jet bigger then optimum shows you on plug and piston tops, will show you zero difference felt in performance on a srx, they actually like a lot of fuel to tractor its way up thru power curve. Get yourself a little flexible bend a light, they have them at hardware stores and like menards, etc. you can look at piston tops and the plugs, theres a lot of information the engine will tell you if you look.
I would use 3M brand #8979 hi-perf duct tape making sure the surfaces are super cleaned with alcohol before applying - inside and out.
It's good for nearly 250F and sticks like a mofo (provided the surface is oil/grease free). Granger and McMaster/Carr carries it.
bADa$$ SRX
New member
Thanks everyone I appreciate all the help.
bADa$$ SRX
New member
White & Nerdy
New member
Ok, so for my dumb question of the day, where are those screens located? I've cleaned my carbs a number of times, but I have never had those out.
you have to pull the pin for the float, then after that's off youll see a small phillipes screw next to the needle and seat, after removing that screw the seat will come out of carb . also pay close attention to the o-ring on them, they dry out and then leak fuel past them, should just replace the o-ring due to age, these sleds are over 20 yrs old now!
bADa$$ SRX
New member
If you can’t get the float pins out use a spring loaded center punch and they’ll pop right out