Checked my plugs after a ride the other day. Stock Viper. I had moved the needles to 4th groove with both washers on top to add some fuel to the mid range after cleaning my carbs this fall. I noticed the MAG side plug ground strap looked a little chalky almost getting white on top after the ride. The other plugs looked the usual nice brown color. The insulators, electrode etc all looked about the same on all 3 with some decent coloring. I just didn't like the coloring on the top of the ground strap on the MAG side. I know the ground strap isn't exactly what to look at on the plugs except for the seeing how far back the burn goes. Would the light color on the strap still be a lean indication even if the insulator and electrode look good and similar to the other plugs with the darker coloring on the straps? I should have taken a shot of the plug to let some of you pro's take a peek. I know the MAG side runs hotter on a Viper but not so sure the plug should look any different. I still need to take a look at the piston wash, check for air leaks, and some plug chops instead of just checking after the ride is over. My guess is if it is indeed leaner or hotter....maybe something got plugged in the carb..pilot jet? (I cleaned them well and made sure I got the screens, made sure the jets were clear along with the usual carb cleaning items) or maybe an air leak? Carb boots are fine and checked the connections well when I put it back together. I will check the crank seal but no idle hang or anything funny going on. I have some work to due but of course it's driving me nuts thinking about it and didn't have time to grab the carbs and bring them back with me or do some more troubleshooting. Checked my other Viper which we took on the same run and all plugs looked the same and nice and brown. Lot's of mid and low speed riding due to crap trails (which concerns me on a Viper) with only a few short WOT blasts on the lakes and wanted to see how things were looking after moving the needles on both sleds. Both run and idle fine. No idle hangs or any issues. Set both sleds carbs up the same as far as needles and went 2 turns out on the screws. At the end of last season I didn't like the coloring on the center and MAG plug on the sled in question....ground strap only portion, which is basically why I decided to raise the needles this year. Center looks great and the same as the PTO side now. Just the MAG has me wondering again.
I guess my questions are.....how much attention should I pay to the color on the ground strap? Any reason why the mag side would look different? Anything else I didn't mention that I should check? Appreciate the info and opinions! It will give me some reading to keep me sane until I can get back to tinker and smell the 2-stroke oil.
I guess my questions are.....how much attention should I pay to the color on the ground strap? Any reason why the mag side would look different? Anything else I didn't mention that I should check? Appreciate the info and opinions! It will give me some reading to keep me sane until I can get back to tinker and smell the 2-stroke oil.
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A couple of bucks
VIP Member
Spray down the mag side of the motor w/ WD40(type).Boots,seals anything that might let O2 into the motor. Do this while running and focus you attention where there are any RPM changes.
I plan on doing that when I dig into it. Still not sure if I should be worried about the ground strap color or not
What's your reasoning for checking the compression in this circumstance...besides it being a good thing to always do?
stanage
Member
Looking at the ground strap will only tell you whether you have the right plug temperature selected. The base ring will indicate your jetting. If you are too lean(regardless of why), the base ring will be white/clean.
To check the bottom end seals, you need to do a "leak-down" test. You can also pull the exhaust, and see if coolant comes out while cranking.
To check the bottom end seals, you need to do a "leak-down" test. You can also pull the exhaust, and see if coolant comes out while cranking.
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A couple of bucks
VIP Member
What plugs are ya running.
stanage said:
That's what I had always thought and the other parts of the plug don't point to lean. Just wasn't sure why one ground strap color would be much off than the others. I will be taking a peak at it anyway.
I'm running BR9EYA's right now. Usually BR9ES but I had a box of the EYA's laying around.
ground strap is only "part" of reading the plug, if its lean it will be burned back past the curve to the housing from the high heat, its not the heat range of the plug.
hard to give you any kind of answer because frankly its too vague of a question and without pics,... pretty tough to give you much more information. No offense meant.
Perhaps you could go to some other recent post and look at some of the plug pics and get an idea what to watch for and then youll be a little more armed for going after the problem if any is found.
hard to give you any kind of answer because frankly its too vague of a question and without pics,... pretty tough to give you much more information. No offense meant.
Perhaps you could go to some other recent post and look at some of the plug pics and get an idea what to watch for and then youll be a little more armed for going after the problem if any is found.
stanage
Member
Reading plugs is a science! I usually carry a mini 16x magnifying glass with an LED flashlight, because I dont want a melt down...
Plug pics
Took some shots of the mag side plug today. Did a little more riding and compared to the others. I guess there is not as much a difference as I thought. Center and PTO are a little darker color wise but everything else looks similar. These aren't plug chops so it's obviously not telling the whole picture. Plugs only have 30 miles on them in low 30's weather . The flash made the color on the ground strap etc look pretty light but in actuality the light coloring is a decent tan...not really "whiteish" as it appears in some photos. Anyone care to throw in some opinions?
Took some shots of the mag side plug today. Did a little more riding and compared to the others. I guess there is not as much a difference as I thought. Center and PTO are a little darker color wise but everything else looks similar. These aren't plug chops so it's obviously not telling the whole picture. Plugs only have 30 miles on them in low 30's weather . The flash made the color on the ground strap etc look pretty light but in actuality the light coloring is a decent tan...not really "whiteish" as it appears in some photos. Anyone care to throw in some opinions?
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gutterboy2ca
New member
had to go look at mine,haven,t pulled them since i bought sled in October, don,t look much difference then yours to me, but what do i know,lol, it runs,,,also compressinos only 92psi straight across all 3, hmm,sounds low to me, time for a freshen up maybe, only got 3400 Miles on it.
YAMMIEGOD3:16
Active member
CLOSE MAN. GREAT FOR RACING. START REALLY WATCHING YOUR WASH. 3:16 (yammie tony)
gutterboy2ca
New member
Hope ya mean laundry,that's only wash term I'm familliar with,snicker....
Hi Bokat, got your pm, heres my opinion on what you have posted, I wrote on your pics for referance. Your pretty close to spot on for the temps your in, you dont have alot of temp drop margin in your jetting. I didnt see the part where you described your throttle setting so I am unsure to advise what part of the jetting to richen up for trail riding safety for temp drop at night,etc.
When you look at a plug:
1.)you want the ground strap to be 2 differnt colors back to the bend
2.)the center core electrode should be just silver on the outside edge of it with a darker center color. This will mean you have about a 10 degree temp drop of safety. If more silver, the closer you are to spot on jetting for the temp your testing in, but you are gonna be lean when the temp drops.
3.) center ceramic core will be 2 colors of tan or brown, youll see a little smoke ring develope on the cone about midway down, this is good
4.) the base of the plug will be dry and the area around the strap will show a flash burn, this can have alot to do with the oil you use but its also something to look at, not near as important as the rest of the plug items.
This is just the plugs, you need to take this and incorporate it into the piston wash readings. You should see a dry piston top and small silver horse shoe marks up at rear corners, sometimes youll even get 2 faint ones on the sides.
If the piston is all dry and no wash at all your on the leaner side, if its all silver around the edge with no carbon and shiny wet center, your too rich.
Its much cheaper to put gas in the sled then pistons so work from rich and go down slowly. You really in my opinion need to be a little richer on the plugs you have posted. The pics of your plugs are what I would be looking for if I was racing or something like that, youd need to be a bump richer somewhere in your fuel curve to be a trail friendly set up with no worrys.
When you look at a plug:
1.)you want the ground strap to be 2 differnt colors back to the bend
2.)the center core electrode should be just silver on the outside edge of it with a darker center color. This will mean you have about a 10 degree temp drop of safety. If more silver, the closer you are to spot on jetting for the temp your testing in, but you are gonna be lean when the temp drops.
3.) center ceramic core will be 2 colors of tan or brown, youll see a little smoke ring develope on the cone about midway down, this is good
4.) the base of the plug will be dry and the area around the strap will show a flash burn, this can have alot to do with the oil you use but its also something to look at, not near as important as the rest of the plug items.
This is just the plugs, you need to take this and incorporate it into the piston wash readings. You should see a dry piston top and small silver horse shoe marks up at rear corners, sometimes youll even get 2 faint ones on the sides.
If the piston is all dry and no wash at all your on the leaner side, if its all silver around the edge with no carbon and shiny wet center, your too rich.
Its much cheaper to put gas in the sled then pistons so work from rich and go down slowly. You really in my opinion need to be a little richer on the plugs you have posted. The pics of your plugs are what I would be looking for if I was racing or something like that, youd need to be a bump richer somewhere in your fuel curve to be a trail friendly set up with no worrys.
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Really appreciate your time and info Mr. Viper. I will be checking piston wash soon. I may try one shim under and over the needle on the 4th groove... as opposed to where I set them this fall with both shims on top and the 4th groove. I do want this sled on the rich...even if it sacrifices performance since it is my back up sled and also gets used by some friends that will ride with me.... some not so experienced... so better rich than lean despite how much I harp on varying the throttle. The center and pto plugs still looked pretty similar after looking again...maybe some darker coloring in most areas.... but most predominantly on the base ring of the plug... where as the Mag plug is more clean in the area that you had marked on the base ring. The others have color running at least 50% around the base. I'm guessing that since the plugs are pretty new....they aren't showing much color there yet. Checked everything for leaks. Boots, crank seal, etc but couldn't find any. Probably gonna pull the carbs off and go through them again in case I missed something or got something partially plugged up on the mag side or in general... might just drop new jets in as opposed to the usual cleaning. Can't hurt to get replace 10 year old jets with some fresh ones. My 04 looks quite a bit richer than this sled with the same needle settings but obviously each sled run it's own way.
As far as the operating range...I deliberately ran it in the middle range since that's what I'm most worried about. Trails were ice, low snow and crap and so it ran hot ...stopped 3 times to let it cool when the light came on. Ice scratchers would have been nice.
Enough rambling and hope I didn't repeat everything from my original post. -) Thanks again for taking a look!
As far as the operating range...I deliberately ran it in the middle range since that's what I'm most worried about. Trails were ice, low snow and crap and so it ran hot ...stopped 3 times to let it cool when the light came on. Ice scratchers would have been nice.
Enough rambling and hope I didn't repeat everything from my original post. -) Thanks again for taking a look!
mag is always the problem child on a viper, wouldnt be beyond me to run a richer needle setting in this cylinder only if thats what the plugs and pistons are telling you it wants. The mag is the hottest cylinder on a viper so its only right it should be the richest. Next hottest one is the center but only due to the compression is slightly higher. The pto is always the richest due to lower compression. So just jet it according to the readings, if your slightly richer on the mag so be it, it should not effect the performance of the sled 1 bit, but it will keep the mr.squeeky piston from visiting you.
as you said each sled is differnt but a richer mag viper cylinder is a safer mag cylinder....lol
as you said each sled is differnt but a richer mag viper cylinder is a safer mag cylinder....lol