Mxz Problems

[sledcrazy]

Ok guys, I know ive posted about 1000000 topics on my MXZ. But, I just attempted to start it up a few mins ago in the garage, and this is what happened. Started w/ full choke on 2 pulls, shut choke off, had trouble idling for a minute then got out of it and idled fine. Pressed the throttle real quick so the clutch engaged, then let the throttle go, and then engine died, and it WONT start back up. I pulled about 25 times, WILL NOT start. So I decided to look at the plugs again..... This is what I found. Clutch side cylinder was a vanilla looking color and was wet, chain case side was black and wet. So the clutch side was fine, but the chain case side was way too rich. A few of you guys said it may have been an air leak a while back, but I checked the airbox and carbs and everything, everything seems to be right. Im pretty much out of ideas now about what to do. ??? ??? Do any of you guys have any ideas?? Me and this sled havent gotten along since day one. Also, the exhaust still leaks from where the pipe fits into the silencer, I tried that gasket maker/sealer stuff and it didnt work. Cant figure that one out either. Anyone have any ideas?? getting kind of frustrated now :hallo1: !!!

[Rocketman]

Sounds like you flooded it. Pull with the throttle wide open and it should catch for you. Make sure your carbs are jetted properly, with the jets in the right carbs with the stagger.
Use Ultra Copper to seal your exhaust: Put a good bead around the inside of the female end then press together and wait 24hrs for it to set before you start your sled up again.

[377safari]

Okay first your muffler problem you can buy muffeler cement that you can put an and when it gets hot and dries it will not come off it turnes in to cement. You may have an air leak the special rubber boot that goes from the carb in to the motor. My sled had that problem and it would not start untill i taped it an deventuly I got a new one. if that helps any.


MATT :blahblah: SWRules

[sledcrazy]

ok thnx guys, ill try that 2morrow morning. ALSO, i just tried to put my rear skid back on, well its not going on. it seems like it wont fit anymore?? i dunno. i got the rear bolt on, then coudlnt get the front on, took the back off, got the front on, now i cant get the back on. ahh sleds are a pain.

[andw1]

Use this thread for getting your skid back int. Some good ideas here.

MXZ Skid frame install

[sledcrazy]

Ok thanks. I guess Ill have my friend over tomorrow to help me with it. Its a pain in the ### doing it by yourself!

[madsledhead]

Sledcrazy,

I like to follow your posts, and I hope to see this beast one day.

Now, I'd like to give you a few good pointers that I hope don't insult you, like I said, I like to try to help in any way. posting carb pics etc. So please don't take things the wrong way.

I mean, I've been where you are several years ago, before I gained all the mechanical experience in this trade, so I know it can be frustrating to not see results immediately.

When it comes to jetting, the first check/inspection must be under STEADY load. I know your hoping to jet it close before actual trial runs, but it's not possible.

In order to check the jetting, you must let the engine run for a long enough period of time to create CONSTANT load. Blipping the throttle and checking plugs will tell you NOTHING.

Take your sled to a groomed straight trail, then run it up to temperature.

To do jetting, your carb temp, and pipe temp, and engine coolent temp must be constant and at steady state.

Run at constant throttle for 1/4 mile. This ensures your pipe and coolent, and carbs are all at normal temp. Then hit the kill switch and keep throttle constant until you get to a stop. now you can look for wash.

You see, your combustion chamber needs to work WITH the pipe temp. Pipe temp has a great effect on back pressure, and this is all part of carb and performance tuning.

When your at STEADY state, your combustion will do 1 of 2 things. It will either dirty your engine, or clean your engine.

If you are running rich, this is where you will see darker plug color because your flame temperature will be to cold to burn off excess oil residue. your piston tops will have a large amount of "wash-out" near the transfer ports.

If you are running lean, your plugs will get cleaner because you are burning off cooked oil due to excess heat from your combustion. Plug "wash-out" will be minimal because of too hot piston tops will bake the fuel closer to the transfers.

This is why you need to run for a longer period, to allow for these things too happen. A small blip of the throttle on the stand may be way too lean, but it's not enough time for the excess heat to burn off the oil from the plugs. And your piston tops wont have enough time to get to steady temps to bake the oil.

In fact, a small blip of the throttle might just be enough pressure to momentarely push some residue oil from the bottom of the crank case to the top. You might think your rich but it could be dangerously lean.

I know your anxious to get it dialed in, thats how I am with my fleet, but we both need to wait for the right conditions to test. I feel for ya man, I am pulling my hair out to see if I'll break the 108 mph mark this year. But patience is the key.

Heres a few tips.

1. Fix your pipe leak first. I don't know what the problem is with the fit, but I garranty if you post a picture everyone on this site will help. Having proper pipe seal is critical for jetting.

2. Use ultra copper on your pipe. I prefer this to cement because of excess vibration. Cement will tend to chip out at the Y pipe. Ultra copper will be more spongy and handle the vibration. (it will actually dampen the vibration)

3. Silicone WILL NOT adhere to oily surfaces. Sand down the areas you are going to silicone with steel wool. then use an industrial cleaner to clear out the pores from the metal. the silicone needs to adhere to the pores.

4. Do initial plug checks for jetting with a USED set of plugs. Like I said earlier, will be either clean them, or make them worse. using new plugs can be deciving because the ceramic insulator coating might prevent some discoloration for a few first hours of operation.

5. Start by jetting midrange. I know I can get alot of bashing from people that do it at WOT first. Personally I prefer to error on the safer side at lower RPM. (just my opinion)

6. make sure carbs are sync. before doing anything. Having one slide higher than the other will throw off your testing and have you scratching your head.


Let me know how it goes.

I hope you don't take it bad If I try to touch the basics, I am sure some of this info you knew already. Like I said, just trying to help out.

Good luck!

[sledcrazy]

WOW! Thank YOU madsledhead!! I did know a little bit of what you just said, but most of that will help me out. Thanks for taking the time to explain it all. The stuff I used to seal it was Ultra black 598. I will try that Ultra copper you mentioned. After I get the exhaust leak fixed, and some cold weather I will get my jetting right. The only problem I have is that changing jets is quite a pain. If i take my airbox off, I need to take the seat and gas tank off to put the airbox back in. It will NOT fit if I dont do that, ever since I put vforce 2 reeds in there it hasnt fit. I will try everthing that you said. I also didnt know to jet on a used set of plugs, thnx for that tip Oh BTW, when I get my sled totally done (it will feel extremely good to do that!!) I WILL post pics of her!! Need to get my sisters digital camera....... But thnx for all the help! So tomorrow I think Im going to buy some ultra copper, get my pipe leak fixed up, have my friend help me w/ the rear skid. Then wait for some cold weather (this sunday were getting a big storm!!! :0: ) So if were lucky enough to get a few inches Ill probably go to my friends HUGE field and make some 1/4 mile runs and get her jetted. I think after that....... Ill be DONE!I sure hope so anyways. Pics will come when shes done!!

[Chubby]

Sledcrazy, Not to be an ###, But you may want to take your sled to a dealer from now on. Leave it to the people who know how to fix a sled.

[Gunner]

personally, even if I've never done something, I would rather
try it myself and learn, before taking it to a dealer. Yes, I've
ended up taking all sorts of parts back to the dealer (MAG
bearing couldn't get off for one example), and having them
finish it because I didn't have the tools or whatever, but
that's how I learn.

I have an 00 with Vforce (and roundslides) and admit the
airbox is tight, but I can still put it on without removing the
tank. I can't say for sure on the 600, but it has to be possible.
I make sure I loosen all clamps (both on the engine side of
the carbs and airbox side) to their max and juggle and fiddle,
while holding the carbs and wiggle it back on. It does work,
but is painful. My fear has always been to wedge one of the air
boots at the bottom of the box and have a leak that causes a
meltdown. I had that happen on a 670 one time. Not fun. I just
make sure the box will slide all the way up on the carbs and
back a little very easily and I ASSUME the boots are on correctly.

One other thought, did you check your pipe and can for any
furry animals living in there? I've heard of others that this has
happened to that caused all sorts of problems with running.