1997 V-Max 600SX engine problem

Thanks for the replys daman.

I did blew through all the jets. The pilot jet is the one with all the small holes in, isn`t it?. Both of them were totally clean from the beginning.

It`s wierd that a plug suddenly will stop sparking from 3000-4500rpm. I will try some other plugs tomorrow maybe I`ll try my SRX plugs.

I don`t think it`s the carbs, they looked fine. I`ve cleaned quite a few carbs and I`ve seen MUCH worse. I remember and old Rotax 583 engine I had. There was about 1 cubic inch of frosen water/dirt in the float chambers, the engine would still run fine, hard to start though.

My boss has a V-Max 600 1996 model , I guess it has the same engine. If new plugs wount cure it, then I might try the coil & CDI from that V-Max just to eliminate them.

I bet it`s the plugs because this engine shouldn`t have bigger issues, it`s a Yamaha.

:)
 
I remember now once we had a '79 exciter that would only idle on
one cyl. till you throttled it. put a different coil on and she ran on two
then. try the plugs then the coil.

Damn we'll figure it out yet......LOL :)
 
:).

I remeber when we picked up this sled, had to ride it about 10 meters on the ground and the sled did run just fine back then, so I guess it has to be the plugs. I`m pretty sure, but ofcourse mistakes/errors can occure even when the sled is put in the summer shed:).
 
hahaha :)

Hmm I wonder where I put the plug wrench... hmm...

haha no only kidding :)
 
haha hey guys !. Nice to see such an enthusiasme! :).

Gees I`m sorry to say it but it seems NOT to be a plug related issue we got here.

The last time I changed the plugs on the sled I put in abrand new BR9ES (had one lying around from my old V-Max) and a used BR9ES that looked somewhat wet/fouled.

Today I removed the old BR9ES and put in a brand new BR9EG from my dirtbike (just to see if it would function better, will not run the sled on that plug in the long turn). I checked the sparks and there was a nice clear/sharp spark at both plugs. I wiped off the BR9ES with a paper towel because it looked a little wet. I put both plugs in and cranked her up. NO DIFFERENCE.

Is it possible that the cylinders/heads/crankhouse can be so covered with oil that the engine just can`t manage to get it clean?. (probably not, hehe, but I remember on my Rotax 583 engine, if it was really soked with fuel/gas I used to take out the plugs and let it sit for a day just to air it out, funny thing, I welded the engine into the frame and I angeled it wrong so that the fuel kept flowing from the carbs to the crankhouse, when I pulled the starter rope I once pulled it off due to the heavy resistance the fuel made in the crankhouse, haha).

I removed the plugs from the V-Max after I tested it, the left side plug was totally cold. The right one was a little hot, could easily hold it in my hand. Sled had idled for about a minute. Wierd actually because it seemed like it idled somewhat on both cylinders. The next time I try it I will put my hands one the exhaust manifoils, I will not be surprised to find the left side totally cold. However, if I ride the sled with lots of rpm I guess it will run on both so basically I haven`t found out anything more today.. .

When looking at the carbs (see the pictures I posted of the carbs) from the air filters view, you see a tiny jet, I did not take those jets out. If one of these jets are plugged could they have something to to with it?. I tried to remove them but my screw driver tended to slip on them so I didn`t want to ruin them. (I did blew through them though).


Gees the last couple of days I`ve fiddled with so many things but if I just put the V-Max on top of my "priorita-ry-ze-se`?" list, then I`m sure I will be wiser.

:)
 
An engine needs 4 things to run: gas, air, spark, and compression. You've verified gas and spark. Pull the exhaust pipe off to verify that nothing is plugging the exhaust system(mouse nest etc.) If the carbs are clean and the exhaust is clean then the airflow should be good, if you have time, pull the carbs again and check the reeds for problems. If everything there still looks good, the next thing is to check the compression. If there is more than 10psi difference between cylinders then you have a compression problem. My money is still on a failed ring/piston. Your video that you posted is exactly how my 97 behaved/sounded when it failed.
 
Yeah I got a good spark on both. However, could still be spark related.. can be fooled.

My friend that have a compression tester is not home for the moment, comes home tomorrow I hope. I will check the compression, if OK then I will wait for the new plugs to arrive. Still no difference after new plugs, then I will remove the carbs again and remove those tiny jets you see from the air filter "side" . Inspect the reeds also. But, do I have to remove the rubber inlets?. In that case I guess I have to get new inlet gaskets.

What gas should this engine run on?. I run 95oct on my old V-Max and I know many others who also runs their V-Max`s on 95oct. The gas on the this V-Max is 98oct, I can smell it. Guess it can`t have anything to do with this issue but I was just wondering.. guess it will run better on 98 but the girl riding this sled wount notice any difference:).

WrdAl I hope it isn`t a piston/ring failure, or, personally I don`t mind I just think it`s fun since I get to wrench, but my friends wallet isn`t that big. Wellwell :).

Gees this is wierd, this sled was suppost to be in top shape.. and it seemed like it when we picked it up.. annoying!.

I`ve read about many guys who change the gas in their dirtbike gas tanks after it has been sitting for only two weeks or so. All my neighbours etc. start and run their sleds on last years gas without any problems, and I have also done that. Never noticed any difference between old/new gas... . I was just thinking that it could be the gas since it probably has been in the tank since March or something. But, I don`t think it`s the gas.. .

hmm
 
kimoaj said:
tiny jets you see from the air filter "side" . Inspect the reeds also. But, do I have to remove the rubber inlets?. In that case I guess I have to get new inlet gaskets.
Click to expand...

yes you would have to remove the inlets to get to the reed cages.

keep plugen away at her ;)!
 
Old gas does make a difference. If the tank was not full when sled was put into storage and it was stored outside there is a real chance that there's a fair amount of water in the fuel, NOT GOOD. Drain the tank and put a couple of gallons of fresh fuel in it.

kimoaj said:
those tiny jets you see from the air filter "side" .
Click to expand...

Those tiny jets are the idle jets and if they're plugged, then that can explain a lot.

I thought you said you'd already cleaned "all the jets".

If you pull the carbs to check the reeds, just be carefull when you pull the boots, there's no gasket seal on there (or at least there shouldn't be any). You should be able to re-use the gaskets. While you have the reeds out would be a good time to do the reed stopper notch. It makes a noticable difference in the mid-range on the 600 twin.

I hope you don't have the ring problem because the cylinders are quite expensive. I understand there are reconditioned cylinders now available for about 1/2 the price of factory new.

Good luck and keep us posted.
 
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Ok :).

Gees I`m looking forward to the weekend, going to help a friend install a 57mm lug belt to his 1994 V-Max 4, going to be interesting:). Have to do quite many modifications to make it fit.

By the way, took my SRX for it`s first "real" ride, (up in the mountains, still very little snow though), and man I must say it feels more stabile then my old RX-1. Not a single bad word about the RX-1 but it felt kind og "tippy" , just like it was going to fall over when hitting a bump with one ski. I really liked the SRX handling, seems stabile and tends to steer really easy. (easy to steer, just like there is no ski pressure at all, but still ti steers imediately without having to hang on the side of the sled).

Last year I made a film from with my friends, I put out on the TY4stroke forum but you can download it if you want to see it, only four strokes though, a few glimts of my friends V-Max 4 though, he almost flips it once:).

Well that`s all for tonight, goodnight everybody! . (the clock is 01.13 here now).
 
Oops I`m still awake hehe.
Hmm I think 01.21 is late enough for a Thursday evening! :). (01.21 night "time" , AM I guess?).

Haha, I should have wrenched on the SX but even if I fix her to morrow I won`t get to play with the girls #$%&* so it doesn`t matter.. hahaha ;)


Well I`d better go to bed. Gees when will it start snowing..

Well anyway :yam:
 
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