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

mtbcates · 11-19-2009, 04:55 PM

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* · 11-19-2009, 10:19 PM

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?

mtbcates · 11-20-2009, 08:52 AM

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* · 11-20-2009, 08:49 PM

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 · 11-27-2009, 09:57 AM

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

rc-11 · 12-26-2009, 01:27 PM

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* · 12-26-2009, 05:47 PM

Quote:

Originally Posted by rc-11

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!