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Discussion Starter #1
Hello I have put a 95 vmax 600 snowmobile motor in a small sandrail and I keep fowling plugs to the point that it only gets full power for maybe 30 minutes then fowls the plugs, I think its the tors system causing the problem. I have put the blk a wht wires together to eliminate it but it still seems to be causing problems. I have the throttel and the oil injection cables both pulling at the same rate. ? is that the problem or do I need to change something else. Any help in this matter would be a great help. Thank you in advance
 

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I think you are too rich.
But it may also be getting too much oil?
You may have to adjust your oil usage then jet it.
Normal oil usage is about 12.5 gal of gas to a qt of oil
If you are going threw a qt of oil for every 8 gallons then adjust it down some a full turn or two.
 

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Discussion Starter #3
That makes sense KCCats2 what do you mean by down one or 2 turns. What do i adjust down. I am very knowledgeable about all the mounting of everything but not to knowledgeable about carb adjustments. is there a screw that adjusts the oil input or is it something with the oil cable
 

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That would be to loosen the cable to turn down the oil usage.
The carb itself will need to be re jetted.
I don't know how rich you are but the Jets come numbered and the lower the number the leaner they are.
So start with what do you have in there now?
 

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Discussion Starter #5
The jets are impossible to read but with a microscope i can see a 5 on both of them. thanks for your help
 

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Discussion Starter #6
Well I decided I would take the carbs off of a doner 94 vmax500 and I couldnt believe they were as clean as new never touched. So I did a quick cleaning and installed them and the motor DID come to life, im taking it to bundy hill and will see how it drives. I will say it does seem like its getting to much oil. I have been trying to put a video up of it but keep having problems
 

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Discussion Starter #9
65181

Oil is cheaper than parts are... just saying! Don't go too lean on the oil.


Ha Guys the motor is running ok but I have a problem. Why is my clutch side cylinder all the sudden not getting any oil the plug is white as new. actually looks like the cylinder is not firing but I checked and both cylinders are firing. Here are the plugs. not sure what is going on. was planning on taking it to the mounds tomorrow for the day but now that i see this its not going anywhere. I am gong to take the carbs apart today and see if there is anything suspicious. I have only driven it a few times and it did have alot more power than before I swaped the carbs with ones from a vmax 500 motor. Here are the plugs
 

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Discussion Starter #10
One other thing was I dd swap the plugs side to side and did not notice any difference but i did not run it for long.
 

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If you have a thermometer gun, it may be a good idea to check the temps of the cylinders. The white plug is either getting no fuel/oil or it's running so lean that it may be very close to melting holes in the pistons. If I pulled a fresh set of plugs and they looked like that, I would really work on making SURE the carb with the white plug is getting fuel and does not have plugged jets.

When the engine is running and you pull the wire from that plug, does the engine still run?

How about if you pull the wire to the darker plug?
 

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I have played with Yamaha Carbs for decades and some just dont come clean! (2 barrel)
I would simply order new main and pilot jets and soak your 600 carbs!
 

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Discussion Starter #13
I have played with Yamaha Carbs for decades and some just dont come clean! (2 barrel)
I would simply order new main and pilot jets and soak your 600 carbs!

Well here is a little update on my progress. I thought I had it running pretty good with 45 jets in it, quite a power increase but i have a extra set of carbs and I put 42.5 jets in them and OMG holly shit now the thing is running like a raped ape, cant keep the tires from loosing traction. going down my dirt rd at say 20-30 and it still looses traction. Now the only problem im having is that only one side is getting oil(clutch side). I have only driven it for maybe 15 minutes. Today i am going to switch the fuel pump with another one off a vmax 500 doner sled. Wish me luck. Let me say this when I have ran it for a descent amount of time the motor does not get that hot, head is never untouchable just hot. To me that is a good thing
 

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Get your oiling fixed!

If it has never ran so good, shut it off she is about to blow!

Check your plugs!
 

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Discussion Starter #15
Alright, just like you said its running just awesome and just unreal throttle response. Bad Ass but it still is not getting oil on one side. I have swapped from a doner sled the fuel pump, the oil pump, and the carbs and put the 45 jets in the carbs. I am running oil in my gas right now just incase. It does seem like it is burning a ton of oil ( smoking like crazy ) and I am taking short 10 minute rides. even though it is smoking the plug on the clutch side is still white as can be, a very faint brownish tinge on one side of the plug. I made sure the drive for the oil pump is turning, I took apart the fuel pump and blew it out. took apart carbs blew them out. The jet needle is on the second notch from top and there is 45 jets in the carbs right now. I have pulled oil line and it is letting oil come out so no plugged lines and swapped line going to fuel pump from oil pump
What else is there cause I do not no of any other thing that has to do with getting oil.
signed: Kinda lost and do not want to blow it up..
 

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Did you bleed the oil pump system after switching it out? That has to be done as well whenever you do that. Not sure how it is done on that engine but I'm sure someone here would know.
 

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Discussion Starter #17
Did you bleed the oil pump system after switching it out? That has to be done as well whenever you do that. Not sure how it is done on that engine but I'm sure someone here would know.
Not sure exactly what your saying to do. What i did is remove it from the sled, pulled the lines off blew them out and cleaned the pump with carb cleaner then reinstalled it since i have oil in the gas i left the line that goes to the fuel pump and oil was dripping from it when it was running. Today im going to put new plugs NGK BR9ES IN IT AND RUN IT FOR 15 AND SEE WHAT THE NEW PLUGS LOOK LIKE. IS RUNNING IT FOR 15 LONG ENOUGH. I NEED
 

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Discussion Starter #18
To get some kind of temp gauge because right now i am just pointing a hand held temp gauge at the head and cylinder. The factory one is just a over heating light and its not hooked up... it does not seem to run real hot to the touch, i have a yamaha 450 4 stroke dirt bike 2 radiator set up now at the top of the buggy. It seems to work excellent.
 

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Discussion Starter #19
Also when should I change the pilot jet. Stock says its a 152.5. I picked up the closest I can get and its a 145. Should I put it in? I am going to put what the graph says it should be for the main jet which is 147.5. i will let you no how it runs later today
 

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STOP!
You are TOO LEAN!
White means it's done! Next is alum on the tip!
There is a bleed screw on oil pump.
If Main (#7)says 155 you want 165 to richen it up
What about the Pilots (#3)
Or that cyl has an air leak?
Check your seals, with it running spray starting fluid see if RPM changes
 
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