93750 no lights runs poorly

9

93750

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i have a 93 750 that runs poorly not a whole lot of power and when idling just does not sound right! sounds like its just running on a couple cylinders instead of all 4! gonna check tonight to be sure all have spark! also noticed none of my lights are working now! (taillights, head lights, gauge lights)! Read a few threads and the symptoms seem to be similar to some others saying turned crank or cdi! but would either of these explain the lights not working? gonna check tonight for turned crank! looking for any ideas or things to test!
 

I`d start by pain stakenly checking every electrical connection...could be a corroaded connection somewhere?
did mice get ahold of it? I`ve heard vicious rumors that they can wreak havic..LOL

did it set for a while?
 
yup tried new plugs! It was only sitting a few days... i rode to work on wed ran great.. went out sat morning to go riding and just ran like crap! tried new plugs did not change anything! i think tonight im just gonna have to go over it closely and see what i can find!
 
check any wire by the exhaust,I had some melt on my srx that were run under the front of the motoer mount that plain got to hot and melted eventually grounding out and causing lights to fail.It did not effect the way it ran so not sure of your poor running condition.
 
I just checked the crank and im pretty sure it is out of alignment. Im wondering how big of a job it is to rephase them and what the job involves?
 
93750 said:
I just checked the crank and im pretty sure it is out of alignment. Im wondering how big of a job it is to rephase them and what the job involves?
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As far as the crank if it is out of phase you need to send it to someone who is experianced with these cranks. I had my done at Northern Crankshaft. John has the jigs there to index it and then he can weld it. He was recommended by another member and I was very pleased with his work. Tom
 
i checked it by using a method i saw on another post! i put #1 cylinder (closest to clutch) at TDC and if i understood it right cylinders 3 and 4 should be the same height and they were not.. one was higher than the other! Is this method the right one for checking it?
 
Yeah thats a okay method..but before concluding the crank is off,.. using three straws, put one straw in cylinder nearest the clutch (lets call this cylinder 1), and one straw in cylinder 3 and another in cylinder 4..then, roll/rock the motor until you get both straws in cylinders 3 & 4 lined up..same hieght..then, slightly rock the motor back and fourth, and see if cylinder 1 is really at TDC???

Basicaly, do the opisite as you did..instead of putting cylinder 1 on TDC, then checking cylinders 3 & 4...
put cylinders 3 & 4, even at half stroke..then check cylinder 1, by slghtly rocking the motor in either direction to see if it up (TDC?) & down the same amount with each rock of the motor in opisite directions.....that should give a bit better result..

Knowing when a piston is truely at TDC, can be VERY dificult without a dial gauge...
at the point where the piston "appears" to be at TDC, the connecting rod, can actually be at a slght angle, which would throw off the other pistons, from where you think they should be at..

When i first got my vmax4, it had burnt down pistons...and..after reading a bit, I started worrying that my crank might be twisted..so, I started checking it with straws...at first, I was convinced it was twisted...then, i read where the 800`s, are`nt known for twisting the crank..so i double checked, still seamed like it was off, so I basicaly lined up pistons in all sorts of differant position, to get more results, and finaly after screwing around with the straws, and painstakenly, measuring a bunch, I figured out it was okay...but again, at first, and quite a few times after the first measurement, i thought it was off...reason is, is because what i mentioned above...
 
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Alright thanks for the help ill definatly try that tonight! definately wanna be sure! ha.... lets just say this is the problem what am i lookin at cost wise? trying to decide weather to fix it or just sell or part out!
 
Tonight I checked the crank with your method and it seems to be ok afterall. Thanks for the suggestion, im glad it wasnt what i thought it could have been. Any suggestions on what to do from here? I checked the spark on all cylinders and they were all ok. Im not sure how to explain how it sounds but it sounds really lazy and powerless. I cleaned the carbs and it ran fine afterwards, untill these problems started. So I dont know if i should clean them again to see if anything got plugged up? Or if there is anything else that might help? Does anyone know if a CDI going bad would cause it to run like crap or would it just not run at all if that was the case?
 
93750 said:
yup tried new plugs! It was only sitting a few days... i rode to work on wed ran great.. went out sat morning to go riding and just ran like crap! tried new plugs did not change anything! i think tonight im just gonna have to go over it closely and see what i can find!
Click to expand...

so it was running great, right up until the minute you parked it...then, after just setting over night, it started, but was running rough? did this coencide, with the lights not working? or did they act up at a differant time??
 
Yeah it sat for a couple days then when i started it.. it just dont sound right! one thing im starting to wonder is if its got some bad gas or water in the gas. It was sitting outside and we got bout 3 inches of snow so im starting to wonder if i got some water in the tank! As for the lights... yes it was the same day that it started running bad.. but im not 100 percent sure when.. cuz i was messing with it in the afternoon ( check carb adustments that kinda stuff) and riding it around the yard and in the field a lil and it wasnt till it started to get to about dusk when i realized the lights were not on! nothing for lights come on.. but the brights do work!
 
Yeah, maybe break out the syphon hose, and try to syphon some gas off the very bottom of the tank...after its been setting still for atleast 30 minutes..then put the syphoned gas in a jar, and see if it looks like this?..LOL
http://img508.imageshack.us/img508/8205/watergas.jpg

Other wise, i cant help but think something got wet?
may want to consider pulling the carbs again...

AL P
 
Are you getting fuel to all 4 carbs,
the Vmax-4 has 2 seperate fuel pumps and I have seen one side frozen up due to bad fuel.
The sled was basically running on 2 cylinders and less than 8000 rpm's @ WOT.

Just a thought...
 
Good suggestion rules!!

and, you could also, maybe feel the pipes (actually, the header connections.right at the head-pre y-pipes) right as you start the sled, and see f they all get hot...and/or, if they heat up about the same time..a little firrance is`nt a big deal, but if one pipe is getting hot, and another is still cold, that`d defiantly be a sign of somethng..

plus, maybe pull the plugs after it running briefly, and see if they show any differences./signs?
 
I think im finally getting it straightened out.. i put a bottle of isopropyl and bout 5 gallons of fresh gas and it seems to be clearing up and running better... as for the lights the bulbs were burnt out so i put new ones in and they are working now!.. only running issue i have now is it seems like #1 cylinder is quite bit richer than the other 3! thanks for all the help from everyone on here!
 
well, if that means it was some moisture/water in your gas..then I`d dang sure lay off any WOT distance runs!!

As far as the lights go..maybe something got wet and caused them to blow..or your regulator is going bad..when my regulator went bad, first the headlight would burn out, then very shortly after, all the excess juice would fry the rest of my lights..but...I`d usually be able to kick on the brights and make it home....before it blew out also..LOL

One thing I noticed about mine when the regulator was going/gone bad, is the headlight would get VERY bright..i mean WHITE bright, like no other headlight I`ever seen..but then suddenly burn out..
 
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