You won't be happy with the aftermarket one.

 

You are probably right about that. Got try something. I am unhappy right now

 

99 Polaris 400 Scrambler ATV-

Where would I check to find the Mikuni carburetor serial number?

I 'm thinking about buying a new carburetor from Niche. It appears my carburetor

is'nt being manufactured anymore. Plus, I'm getting tired of fussing with it.

Thanks in advance!

Your Cousin

There is no serial number on the VM carbs and generally no model number either.

Polaris did not renew their contract with Mikuni for more SS style carbs and they have been gone for over 20 years, but Mikuni still sells the VM carb. You just have to jet it to your application.

A genuine Mikuni VM34 carb is $150 new. But since it needs to be jetted anyway, if you get the NICHE Chinese counterfeit and can find jets to fit, it will work fine after jetting.

 

Thanks for getting back to me. I know that I might be damned for going this route. I know for sure

that I am damned with the original on the ATV. After rebuilding it twice, its time to do something

different. Getting unburnt oil and gas out the exhuast. Will not idle, checked throttle cable, fresh gas, new

air filter, rebuilt top end, good compression... after all, this unit is 25 years old. Still in great shape. Has not been abused. Can't see spending

thousands of dollars when there is a chance I can get it up and running. Right now, all I have is a boat anchor taking up space in the garage.

Thanks again Old Hunter 1

Your cousin

 

What did you "rebuild twice" what parts did you replace?

 

I replaced everything in the carburetor that came with the kit (not Chicom kit). I also dipped the

carburetor in parts cleaner overnight and dipped it in hot water and blew it out with compressed air.

I checked closely to make sure that the new parts were the same as the ones I was replacing. I then

installed it on the ATV.

When I could not get the ATV to idle, I took the carburetor apart again to see if I had done something

wrong the first time. It looked good and I reinstalled it. Still will not idle.

Got to be something wrong with carburetor body. I've watched videos of guys taking these carbs apart

outside with dirt, grime everywhere. They put back it back together and it works. It really is a head scratcher.

 

Have you tried power sports nation or another salvage yard?

 

I didn't even consider that. Never crossed my mind. This is why I like this forum. I will check PSN and see what I can find.

Thanks 2 XP

 

Can you get the engine to idle if you hold the throttle steady at a specific point? If yes, you only need to adjust the idle speed screw. On the VM carb the idle air screw just needs to be set at 1 1/2 turns from lightly seated.

 

Yes, I can get the engine to idle at a specific point. I do have the air screw turned 1 1/2 turns now and earlier as well. Sure wish that was all it took,

but it is'nt. This engine has smoked for quite some now (prebuild). I actually can get it to smoke alot less than before. Not sure if that is the sweet spot or the

path to blowing it up... I main thing is that it still won't idle.

Your cousin

 

what is the compression reading

 

I just redid the top of the engine. 135 psi

 

Your cam timing might be off by one tooth

 

Thats sounds like something that's out of my league. If that is the case, I guess there won't be a bandaid for it.
Thanks

cousin

 

If you just redid the TE of the engine, the cam timing is just a part of the procedure - how would it be out of your league since you have already been through it?

 

I just replaced the rings, piston and jug, same as I did 5 or 6 years ago. The only thing different this time was that I rebuilt the carburetor. Last time I did not have

problems with carburetor. I guess the first time I got lucky. What should I have done that I didn't.

Thanks

Cousin

 

Take the cover off the cam sprocket, put the engine on TDC of the compression stroke and check the alignment of the timing marks.

 

I guess this is where I show my ignorance. Just where would I find this cam cover? Right side of engine? When I get this off, then the timing marks will be self evident???

TDC ?

Thanks again

cousin

 

Well, I feel better now that I'm not such a dummy as I thought I was.

2XP suggested "Power Sports Nation" for a used one. I could not find a carburetor from them. They appear only to deal in newer vehicles parts.

Other than taking the ATV outside and setting it on fire, what would you do? Sounds like I should find a used carb and rebuild it. But where to look

for one is the question. The other option is buying a chicom unit and cross my fingers and toes that it works. You mentioned this option. But its the

rejetting that's the trick. Would I just order a rebuild kit for my current carb and hope that it works on the chicom unit?

I think the best answer is finding a used unit and rebuilding it. But where would I be able to get a used one?

Thanks

Your cousin

 

Ebay is a great place to find parts, PSN is also on ebay and I have found that if they are out of stock online they will have it on eBay. If not someone will.

 

Sounds like a great place to starting looking. I appreciate the info.
Thanks Gary

cousin

 

In searching for a good used Mikuni carburetor, will any Polaris ATV MK-VM34 do the job or do I need to be more specific looking for MK-VM34-8441?

I would hate to order something only to find out that it is the wrong carburetor for the job.

Thanks

cousin

 

It appears I just sold the last VM34-168 carb available in the California Mikuni warehouse - they are now on back order.

Would you be interested in sending me the Mikuni carb you have and let me see what I can do with it?

 

I did find a couple of NEW Mikuni VM34-168 carbs on Ebay - Lowest priced one HERE - anything priced lower is a Chinese counterfeit - you will still have to jet it for the application, but jets and such from the one you have will fit.

 

That sounds like an idea. So you think this unit is salvageable then? I know for sure that I have to do something with it. So yes, I would

be interested in sending it to you. How do we go about this?

cousin

 

Or I could go with the one on ebay and switch out the jets. But are we fairly certain that this carburetor that is listed for a banshee with work with

the polaris 440?

Thanks again

 

Sent PM

 

Latebird- UPS has the package and you should get it by this Thursday or Friday.

Thanks again

Your Cousin

 

OK - I should have it apart and inspected within an hour of receiving it.

Do you live in Wapakoneta? I used to work for a company with a facility here in Clinton and dealt with with The Wapakoneta Machine Co. located at 300 North Street.

 

Latebird- UPS has the package and you should get it this Thursday or Friday.

Th

I live 30 miles East of Wapak. Wapak is the home of the first man to step foot on the moon..... Neil Armstrong.

Looking forward to the prognosis of the unit.

Your cousin