97' Vmax 600 Problem

braindead1684 said:
The problem with running premix and the pump is you are running the engine LEAN on gas. the oil/gas is mixed in the fuel pump and pumped to the carb mixed essentialy you are pushing 25:1 gas/oil mix instead of 50:1 then the oil that drops out leaves you with very little gas. It is very possible this is the reason it is backfiring and not running. The oil and such you are seeing is the excess you have as there is way too much in there especially if the oil pump was too high. I personally don't run any extra oil in the tank on rebuilds.
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Most guys run extra oil because they don't lube the parts during re-assembly.
The fuel mix he is running should not hurt anything. I have done exactly what he is doing and have not had a problem.
Sounds like it could be broken reeds, faulty plug caps or wires, or other mechanical issues.
 
Just a thought.. you indicated that the choke/enrichener does nothing. I would look deeper into that. Ensure the choke lever/linkages move from fully closed to fully open. You may be trying to run with the choke/enrichener 1/4-1/2-3/4 or fully open!?!
 
Ya its weird about the choke....however it was simply disconected and re-conected....the adjustment should go out and it seems to be working fine other than the sled does not want it on for sure....I wouldnt think the fuel mix would be that bad....its mixed like I have mixed in the past on rebuilds.....the oil pump was WAY too high though....im glad we turned that down....do you think a reed could cause this problem....as far as the plug caps....there seems to be lots of spark and no arking that I have seen....what can I try to eliminate some stuff....
 
If you turned the oil pump down on a pump that was the original part, it will do nothing to lower the amount of oil that gets pumped into the engine. I learned this out last season. If you have the original pump, and I bet you do, you need to replace it to get the oil volume at an acceptable level. When they fail, the internal mechanism just goes to all out volume and will not adjust anymore.

Also, if one carb slide rises or lowers out of synv with the other, you need to re sync your carbs. Carbs out of sync will cause all sorts of bad running issues. Add in a faulty oil pump, and pre mixed gas, and you will only make the engine run even worse.
 
my buddy did the same thing as soon as he press the gas it was bawging and back firing all it was, was his SPARKYS, he changed them to BR9ES to BR9ESYA isnce then it work fine
 
threw a pair of eya's just to try but no go....it did seem to burn an awful lot in the short ride on the lake....it was full to the top and in the 20-25 (20 miles) trip it prob burnt almost 3/4 of a quart....I did turn the pump down but how would you check to see if its faulty....do you think I should try fresh gas.. straight...? The carbs being a small amount out of sync will cause this?? I thought it would still fun but just not to optimum performance...? Im not sure...
 
If you used that much oil in 20-25 miles, you can bet the pump is bad.

Daman, or anyone else that is good with the fuel oil ratio amounts chime in, but 3/4 of a qt in lets say 2-2.5 gallons is too rich.

Ours was that bad with the old pump.

Yes, the carbs being out of synch just a little will cause poor running and backfiring. That is why synching the carbs requires a tool to measure flow and not eyesight.

I think you should disconnect the oil pump cable, and leave the fuel mixed at 50:1 and see if it runs better. If it does, then that is proof that the oil pump is bad. Granted it won't be perfect until it is re synched, but it will eliminate 1 variable.

After a re synch and a new oil pump, our venture has a ton of power, enough to hit over 90 on a snowy lake. Pretty good for a 6000 mile 12yr old sled that happens to be a 2 up.
 
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I Agree with Bypassing the oil pump. If that is faulty and dumping oil you already are pre-mixed at 50:1 so you will be fine running it like that.

If you unhook the cable from the oil pump will it actually stop pumping (when faulty) Just a question as it seems like when it failed it may cause it to flow even without pulling the cable open.
 
I just rebuild my 97 MM600 I added 1.5 quarts of oil to 10 gal. of gas rode it 120 miles on sat. ran like a champ You sure you dont have a CDI box or stator problem?
 
I will disconnect the oil pump next and try that....thinking its prob the pump too....looked on the odo...and we only got 6 miles and about 3/4 qt of oil....hopefully we will solve this problem....
 
so disconnected the oil pump and tryed to start the sled and wouldnt even fire....checked for spark and NOTHING...now I lost my spark...had what seemed to be good spark before and now nothing....could it be possible that I had an electrical problem this whole time..? Could the coil or stator have gotten worse to the point where it no longer works....how can I check my coil..? Does anyone know the spec OHM to read for ...? Can someone give me some direction on my spark problem now..?
 
Interesting.

Try hooking the oil pump up again and then try to start it.

3/4 of a qt of oil in 6 miles is UNREAL. That alone should tell you the pump is bad.
 
I agree that the pump is prob shot....but now I need to addresss the spark issue...I would like to test the coil but not real sure how....how often do they go...? The sled progressivly got worse to the point of not running.....do the plug boots pull off or not? One came off and the other wouldnt budge...just dont know what to try now?
 
i have an 02 viper every time i hit the little bit of powder it bogs and wont move where is the powder getting in at ?how do the mountain vipers go so good in the deep stuff and mine wont move
 
THe caps im not too sure about....im gonna say that most stuff is the original parts....we picked it up last yr with a blown motor....had about 8000 km....rebuilt it finally and it ran GREAT for the first 1/2hr ideling....seemed to be all set right....took it out the next day for a rip and it ran the same for 6km....after that it started this problem which only got worse running it to the point were it would barely run on 1 cyl to would not run.....and now we lost spark....im wondering if something electrical (coil/stator/cdi) can get progressivly worse in that short amount of time.....I tryed to pull the plug boots of and one came with a little twist/pull....the other wouldnt come off...then I started to wonder if maybe they are not suppose to come apart....if they are I will get that other one off and swap out with new ones to try...? I def need a manual too but I like people idea's more....
 
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