Hi all I just bought a 04 AC 400 4x4 and have no manual or any clues about this ATV. I am trying to figure out the seat removal and need some tips on what PM to do and anything else you can suggest. I'd like to change the oil and put a new plug in for starters, any advice or tips you can give me will be greatly appreciated.
Thanks, John

 

To take the seat off there should be a lever under the tail light you pull out to unlatch the seat. Lift up on the back of the seat to remove.

For changing the oil if you do not already know if it has synthetic oil or not? You need to stay with synthetic if it has it in it but if you are running normal oil you can switch to synthetic if you want to. Just make sure what ever oil you use if it is not AC brand is "wet clutch" safe or the clutch will slip. Also, I would get an oil filter from an auto parts store. (FRAM 1359 I think for the AC 400/500 cross reference it to your desired brand if you need to)

Plug type is an NGK-CR7E Buy two just so you have one as they are like $4 each.

Also, check ebay and get yourself a manual. They are very nice to have.

TIPS:
Look your tires over and see what kind of riding you area going to be doing and look at tires that will match. Get rid of the stock dunlop tires if that is what it has they are fine for some trails but there are much better tires out there.

Check and change the differential fluid as well as the oil. Use a hypoid 90w gear oil.

Give your brakes and bearings a look see as well.

Then, RIDE!

Swampy

 

actually i believe the seat latch is on the right side under the front of the seat right beside the frame down tube. i have an 02 300 4x4 that im servicing and it took me forever to find that thing

 

Thanks guys I got the seat off but no book under the seat. I plowed a little snow today but it is very hard to move the gear handle between reverse and H. I should have mentioned it is an automatic. It has ITP mud lite tires on it. If I do use synthetic oil does it matter what type with the auto trans ? Also how do I get to the air cleaner to check the filter, does that plastic just pop out ?
Thanks so much again, John

 

Go to Bittorrent.com or vuze.com and do a search for AC service manuals. I have found manuals for all kinds of quad there as PDF files.

 

Regardless the oil you use it has to be "wet clutch" safe.

The hard shifting can becasued by a rusted shifting linkage OR high idle.

Swampy

 

Thanks for the help...Does anyone know the bulb #'s for the
headlights ? Can you pick them up anywhere ?

Thanks again, John

 

Headlight buld number should be written onthe side of the bulb if you can still read it.

It should be 12V/37W bulb. AC Part Number 0409-045 and they run between $25-$30 each from a dealer. Make sure you do not touch the bulb with your fingers during installation adn that the lens housing seal is good or they will burn out FAST!

The last one I repalced on my machines I got from Car Quest for around $15 and it is still going.

SJ