1997 Polaris Scrambler 4X4 400 transmission Grinds in forward - Any ideas ?

[mtbcates 10]

Hi all , I have a 1997 Polaris Scrambler 400 4X4. It will not go into forward and if you keep at it and it does go into forward gear it will pop back out if you are going down a hill and your rpm's drop. It goes into Reverse very easy with no grinding. It grinds like crazy trying to get it into forward. You can hear it click into gear then all you hear is a light grinding in the transmission that get louder with the rpm's raising without going into gear. the 4X4 works fine.

Sometimes when you get it into gear it will stay in gear for awhile before popping out and sometimes it will stay in gear just a few minutes and then it takes anywhere from 5-30 minutes to get it to take forward again.

Before i tear the transmission down , does anyone have any ideas what i'm going to run into ?

Thanks for the help

[outlander560 10]

Well some ideas i have are: your rpms are set to high on ur carb the motor is working to fast at idle causing the gears in the tranny to move fast...and when you try putting it into gear your fork inside the transmission is having trouble grabbing the gears....The second idea is that you shift linkage needs adjusting its a simple fix...Third idea is that the fork used to select high gear is worn down really badly so it will not grab the gears as easy as it should...if i remember correctly there are to forks inside the transmission, one for reverse and high gear and one for low gear...so possibly the high gear and reverse gear fork needs to be replace...

Have you changed your transmission oil? were there metal shavings in it?

Edited November 20, 2009 by outlander560

[mtbcates 10]

Thanks for the reply , the shift forks is sounding like the issue , the Rpm's are idled down low with no issue going into reverse. Checked the oil and it had no shavings in it that i could see. I'm going to pull the Transmission apart this weekend and try to find out whats going on with this forward gear.

I could only wish it is the linkage but I'm afraid it's more serious cause when it finally goes into gear you can hear the grinding after it goes into gear and of course it get louder with the rpm's.

[DirtDemon 12]

The grinding noise is probably a result of the gear not being fully engaged, that is also why it pops out. It is most likely the shift fork, but it would be worth your time to try adjusting the linkage to see if it helps.

[ELIOT 10]

Look at the nut on top of the tras. May to be tighten. And the shift linkage

may need to be adjusted.

[rc-11 10]

hello mtbcates,

I was just browzing and ran across your post. You described the problem I was having to a tee. I just had to register so I could give you the exact answer to your problem. I am currently in the process of doing the same repair to my 1998 400 sport. If you have not already opened the tranny case or when you do you are going to find what they call the Forward Sprocket/gear and the Forward Engagement dog are damaged. They have little ears or (dogs) that get the edges ground away causing it not to engage properly. I ordered my parts from this site Motorcycle Parts, Motorcycle Accessories ? BikeBandit.com . They have great diagrams to show you the parts. My engagement dog was $95 and the Sprocket/gear was $68. hope this helps you and others with this same problem!

rc-11

[Ajmboy 438]

hello mtbcates,

I was just browzing and ran across your post. You described the problem I was having to a tee. I just had to register so I could give you the exact answer to your problem. I am currently in the process of doing the same repair to my 1998 400 sport. If you have not already opened the tranny case or when you do you are going to find what they call the Forward Sprocket/gear and the Forward Engagement dog are damaged. They have little ears or (dogs) that get the edges ground away causing it not to engage properly. I ordered my parts from this site Motorcycle Parts, Motorcycle Accessories ? BikeBandit.com . They have great diagrams to show you the parts. My engagement dog was $95 and the Sprocket/gear was $68. hope this helps you and others with this same problem!

rc-11

Good info, glad you registered. Be sure to stick around!

[Scram400bler 10]

I have a problem that finally did it today on my 98 scrambler 400 while pulling a snow tube, don't always pull a tube though, just playing too. I bought this atv 4 months ago. Had no problems with it then until the last few times I ran it. So I found this forum and decided to join it. I also have a gear grinding issue in forward gear, no issues in reverse or 4 wheel drive. Now gears are always grinding while in forward gear and shifter won't stay in gear too. Tried holding gear in forward, but it just grinds, no moving forward. So I drove the atv backwards in the snow cover yard all the way back inside my garage. So now I guess I will have to tear it apart to fix those gears. My question is what are the part list numbers for those gears and how long would it take to replace them? Thanks for your help...

[DirtDemon 12]

Sounds like you are having the same problems as everyone else, so, if you haven't already read the other posts in the thread. If you look on most any online parts store, they will have exploded parts diagrams with part #'s. Servicehonda.com, Babbitsonline.com, BikeBandit.com and Rockymountainatvmc.com all have these features, and all of them will have better prices than dealerships. Shop around, one place may have the best price on one part, but be a bit higher than other sites for other parts. As far as you question about how long it will take to fix it, that all depends on how experienced the person doing the work is, and what exactly you end up having to fix. If you find out any more detailed info about your problem, do tell us, it will help us help you. Good luck.

[Tinkerman 11]

My money is on the silent chain inside the transmission its the most common thing to go out but ive seen bent shift forkes before. If you crack it open Id replace the chain as well its less than 60.00 better to be safe than have to pull and do it all over again..

Good luck Polarisatvrepair.com

[Scram400bler 10]

My scrambler is working again. Had to replace the fork, 3/4 worned out. Also replaced the dog gear, all 3 contact points were gone, and another gear that connects with the dog. Found out it had no transmission fluid in it, it was leaking out. Had to replace the drain plug too, the heat with no tranny fluid fuzed the plug. But got it out. Also change out the filter and clean the carb too.

[motoman7991 10]

I am also attempting the same repair now. what all will I need to remove off the quad to get to the gear box?

thanks for the help!!

[marioweldinginc 10]

I was told i wasnt allowed to answer :beer:

Sent from my SGH-T959V using Tapatalk

[Scram400bler 10]

Lots of patience. I had to take off the whole engine and tranny together. First I disconnected all the plugs and hose to the tranny and engine parts. Took rear a-arm and axle out of the way, had to jack the rear end in the air to do this. Front drive shaft and whatever bolts were left for the assemble to be pulled out. Tight to lift the assemble out to side of 4 wheeler. I also took pictures of what eveything looks like before I started the job. The manual I had didn't have very good pictures which I found online for free, but don't know from where.

[oxidized_black 75]

The manual I had didn't have very good pictures which I found online for free, but don't know from where.

will this help?

World of Powersports' 1997 Polaris ATV SCRAMBLER 400L (W97BC38C) Sections

[motoman7991 10]

alrighty thanks yall. its gonna be a long week. but thanks for that manual!!!