Well got the motor all put back together. And it runs great. I couldn't ask for a better running motor. And pep, that thing got some pep. Now as for the break in what should I do. And I have a question about the tranny. When I first got on it to ride it. The transmission made noise really bad. Even going 5 mph. So I checked the gear oil. There was none. So I filled It up. But It still makes the noise. I think When it got empty. Someone kept driving it and now. The noise Is permanent. So Is there any way of quitting it down. Or do I have to try to rebuild it. And were do I get the parts from?

 

Just vary the throttle over about an hr period,but not wide open. You can let it cool down a little during the first hr or so to help the rings seat. As far as the tranny I think you're next job is to tear into it if it's been driven without oil for a while. Bearing noise,chain and gear whine can be a little distracting. Bearings are no problem,in fact cheaper if you just read the "universal" number on them and get them from Napa,etc rather than paying even the online places for them. Hard parts if needed(gears,shift forks) may be just that,hard to find.Some may be NLA,but always replace the silent chain and seals. Just have to check online places like Partzilla and here for a starter. Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse Hopefully just a couple bearings need replacing along with the silent chain. Check the engagementt dogs on the slider gear and mating gears along with the shift forks. A good manual can help,but there are several videos that can help also.

 

I have a ? about the tranny. Witch chain is witch long one short one. And what bearing and or gears do you think need to be changed.

 

Videos were just an example on internals,wasn't the Express 300 transmission. It only has one chain. Once torn down just check each bearing by rolling around slowly. Check for any noisy or rough feeling bearings.

 

Well I got the Tranny tore apart. There are a few problems. #1. The chain Is so lose that I can pretty much take It off without removing any of the gears. Now, Will that cause It to wine when driving? #2. I found a piece of metal in the bottom of the tranny that I don't know where it goes. It is about 1 1/2" long and about 1/2" wide. Do you know were it goes? All the bearings look and feel good. They turn nice and freely. And there is no side to side play in them. What does a gear look like when it is wore out? And the main gear. (The biggest one) I did noticed that It Is moving side to side and it has scraped the inside of the case. And you can see on the gear where is has hit the case. What would cause that? And what would be the best way to fix a hole in the case. At some point the chain came of and got wrapped around the sprocket and hit the case and put a hole in it. And that is why it didn't have any gear lube in it. Its not a big hole but it is enough to leak all the fluid out.

 

Wow... Chain for one has to be replaced,only pieces of metal I can think of is either the shift lock bracket or pins,#20-21 or the oil deflector item #48. Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse There are a couple small needle bearings that need to be looked at along with ALL circlips and the shafts themselves. I for one wouldn't reuse circlips,but people have.The gears need to be removed from the shafts and inspected especially the engagement dogs and mating gears for wear. Shift forks also for any excessive grooving. The chain itself could have eaten away at the case if that loose.Any bearing that you may suspect should be changed and you can just use the universal part number on them at any auto/bearing house.Always replace the seals also. JB Weld on small places can work,if not case may need to be welded. Don't know If I referenced the manual on this,but can really help on what to check if I've missed anything and has good pics and detailed instructions on the gear case.DOWNLOAD 1996-1998 Polaris ATV Repair Manual ALL MODELS - Download ...

 

I have a ? for u. I got the tranny all put back together with the new chain bearings and seals. And the tranny itself does not make any noise. But it is still wining so I traced it to the output shaft. Where it goes trough the BRG.ASM,O/P SHAFT. Oem part# 1590237 There is a bushing inside that ASM that is wore out. And it also chewed up the output shaft. So I have two problems. 1. I can not find the out put shaft any where. 2. Can you buy just the bushing for the BRG.ASM? Or do you have to buy the whole ASM witch is about $80.00

 

Sorry to hear that... At least you have the gear case fixed as probably the worn chain could have damaged more in the gear case than it did if you had waited.A lot of parts are becoming NLA for this and other atvs now and the only way to get another output shaft is to find one in a used gear case plus the bushing was never offered separately just came in the complete bearing housing.That's not saying you couldn't try to make one or find something that might work. Other than that a new housing or take a chance on a used one,which I wouldn't from ebay.Problem is most are either damaged/worn out over the years especially if people never kept them greased.Don't know how many I've had to use an air impact on just to remove them from the shaft after they were frozen in place. After I got through with them they were junk any way and got replaced.http://www.ebay.com/itm/1994-1995-Polaris-300-400L-4X4-6X6-POLARIS-OEM-Output-Shaft-Bearing-Assembly-/281495609292?hash=item418a721fcc&vxp=mtr One thing that could be done rather than tearing the gear case apart "IF" you have room is to have a machine shop build the worn shaft area up and turn it back down to match the rest of the shaft.But if they can't do it in the frame that may involve having to pull the gear case back out or removing the shaft which may not be worth the effort. P.S. if it's any consolation the bearing assy is 49 bucks here.. http://www.cyclepartswarehouse.com/f...1997&fveh=5438

 

I had to take the tranny back out to remove the out put shaft. That was no big deal. I am going to have a shop fix the shaft. I would like to know if the BRG.ASM from a 99 explorer would work It has a bearing not a bushing. Im think it would as long as the shaft DIA. is the same. But I cant find any reference on the diameter of those shafts. Here are the part number 2201115 It is out of a 1998 Polaris big boss. here is the page where I found it. I can get it for $31.99 On http://www.chaparral-racing.com
http://www.partzilla.com/parts/searc...ING/parts.html

 

Newer brg supports did use a ball bearing rather than the plain bearing,but can't say for sure this would retro fit. Only way for sure would be to buy it and check the inner diameter versus your shaft. May work or may just end up being a 32 buck paper weight if you cant use it. The main problem with the older style is that people never greased them and they froze up or grooved up the shaft like yours has done. If you get the correct one,keep it greased,it'll last longer than you'll probably keep the atv.