Super Jet sparkplugs with some deposits on them?

davy87nj

davy87nj

Location
Santa Maria, CA
So recently I have been going thru plugs quite a bit. I think a set of plugs should last longer than 15 gallons of fuel bring run thru the ski. Recently I have been putting the ski in for the first ride of the weekend and I crank and crank and it doesnt go. Pull the plugs and find some deposits build up causing the plug to sort of ground to it self instead of jumping the electrode gap. I can actually see this happening because when I crank the ski over and have a plug pulled touching the electode to ground it wont spark. If I make a good 20 to 30 thousands gap between the electrode and a grounding point the spark will jump from the electrode to the grounding point. Recently I have been cleaning the plugs real good removing these deposits and it will run fine all weekend. My question is, is what is causing these deposits? :):):):)ty oil? low compression? the fact that I do suck in some water from time to time? too rich? I have yet to do a good diag on the plugs to see what color they are after being ridden. I have to bring some tools to a launch ramp to do it since I set the ski in with a davit and I dont like pulling the hood while the ski is floating. Also have to test compression. Im running that pennzoil stuff you can buy a wal mart, premium fuel, 92 or 93 octane. stock 650 SN. Seems to run good but I have very little to compare it to except 550's. Never ridden other SJ's.
 
Dutchie

Dutchie

Location
nederlands
Hey,

My plugs are in my x2 for 2 sezons.

When the clog up with black resedue u have a low budget oil or to low of a combustion temp. If the electrode is Nice brown collort and the edge is blacked out its to much oil.

With a good high tech oil you dont Need to have a rich oil mixture, clean those plugs and get some full syn oil, like racing oil from castrol! Then see what happends.

Greetings,
 
BruceSki

BruceSki

Formerly Motoman25
Location
Long Island
have you actually changed the plugs or just keep cleaning them?

Have you cut back the wires so you have good spark and not weak spark?

Might be weak spark giving an incomplete burn.

Next thing I would say after that is a weak stator causing weak spark, if cutting the wires and replacing plugs doesn't help.
 
Last edited:
davy87nj

davy87nj

Location
Santa Maria, CA
I have replaced the plugs. To cut back the wires how far do you cut back? If they had corrosion thats obvious. But do you just cut the part of that was originally connected to the boot? Thanks for the info, thats something I will look into.
 
BruceSki

BruceSki

Formerly Motoman25
Location
Long Island
You have to takes the boots off then pull on the electrode inside the insulation. It is usually broken at about an inch back. Cut it back to there and reinstall the boot.
 
Cannibal

Cannibal

Tasty Human
Location
Summit Lake, WA
I wonder if it's possible that you are running lean (causes more deposites), then you ingest a little water and that cleans your pistons off and the deposits get stuck to your plugs.

Maybe it's unlikely, but I guess it might be worth taking a look at. Maybe pull your head and take a look at piston wash if you run out of other ideas.
 
davy87nj

davy87nj

Location
Santa Maria, CA
I checked compression, got 125 in both cylinders. Is that too low for a stock 650? After I ride around a little plugs look ok, a dark brownish color. Ski sat for a week, went to start today and it wouldnt start. Same deal had to clean plugs, then it fired right up. Seems to be an issue after it sits for a little while.

I cut back the wire a little, they looked ok tho. No corrision, no breaks I could see.
 
Last edited:
You must log in or register to reply here.
Top Bottom