Help! AX15 seems to be stuck in 4th - JeepForum.com

 
LinkBack Thread Tools
post #1 of 10 Old 02-23-2013, 10:10 PM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
Help! AX15 seems to be stuck in 4th

I just put my AX-15 back together and all appeared good. Followed the book, no parts missing or extra, pics together match pics before etc. Anyhow, it turns in 4th and neutral but in any other gear it is stuck like it is in 4th + whatever gear. I took pics before I put the case on and it sure appears that the 3-4 selector is in neutral but it is not behaving that way. Any ideas?

RenoF250 is offline  
Sponsored Links
Advertisement
 
post #2 of 10 Old 02-23-2013, 10:16 PM
Mean Max
Don't poke the bear
 
Mean Max's Avatar
1991 YJ Wrangler 
 
Join Date: Jul 2007
Location: Stuart, Florida
Posts: 13,734
It sounds like you might have the syncro for 4th out of alignment. Specifically, the 3 hub key cutouts.

Max

Click here to see all of my different albums on Photobucket.
Choose any album to see all of my pics!


Quote:
Originally Posted by UltimatE View Post
Max has a picture of every Jeep part ever made.
Quote:
Originally Posted by Benderff View Post
No one here knows what they are talking about. You should try Pirate 4x4 they will be happy to help you.

There is no situation that cannot be improved with a small but well-placed explosive.
Mean Max is offline  
post #3 of 10 Old 02-23-2013, 11:26 PM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
I pulled it apart before the RTV dried and the 4th synchro was jammed on. I pried it off with a screwdriver and now it works fine. Put it together with no RTV and it works fine. I made sure all of the synchros engaged the keys properly. Something apparently jammed it on. The thing that really concerns me is the reason I am rebuilding this transmission is the 3-4 keys were broken. This seems like just the sort of problem that would break the keys. Is there something wrong with the pilot shaft or is this just a coincidence?
RenoF250 is offline  
post #4 of 10 Old 02-23-2013, 11:47 PM
Mean Max
Don't poke the bear
 
Mean Max's Avatar
1991 YJ Wrangler 
 
Join Date: Jul 2007
Location: Stuart, Florida
Posts: 13,734
I've had 4th gear syncros get jammed onto the input shaft before myself. It hasn't happened to me since I started loading the syncros grease while installing them.

As for the original condition regarding the broken 3-4 keys, I've never seen that before. Were they all broken? Was the hub shift sleeve on correctly, chamfered edge to the front?

Is the pilot bearing present/correct?

Max

Click here to see all of my different albums on Photobucket.
Choose any album to see all of my pics!


Quote:
Originally Posted by UltimatE View Post
Max has a picture of every Jeep part ever made.
Quote:
Originally Posted by Benderff View Post
No one here knows what they are talking about. You should try Pirate 4x4 they will be happy to help you.

There is no situation that cannot be improved with a small but well-placed explosive.
Mean Max is offline  
post #5 of 10 Old 02-24-2013, 12:25 AM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
Quote:
Originally Posted by Mean Max View Post
I've had 4th gear syncros get jammed onto the input shaft before myself. It hasn't happened to me since I started loading the syncros grease while installing them.

As for the original condition regarding the broken 3-4 keys, I've never seen that before. Were they all broken? Was the hub shift sleeve on correctly, chamfered edge to the front?

Is the pilot bearing present/correct?

Max
Yes, all 3 were broken and both 3 and 4 synchros toast. Also front and rear sealed bearings had bubbled plastic other than that no damage that I saw. It appeared to be the factory build. I cannot comment on the pilot bearing, I bought if from a guy on CL already out. The synchros were all completely worn out so that they were bottoming out on the ramp.
RenoF250 is offline  
post #6 of 10 Old 02-24-2013, 05:42 AM
Mean Max
Don't poke the bear
 
Mean Max's Avatar
1991 YJ Wrangler 
 
Join Date: Jul 2007
Location: Stuart, Florida
Posts: 13,734
The bubbling sealed bearing condition is typical.

Syncros in the AX-5 & AX-15 transmissions most commonly wear on the backside, where the keys engage, rather than on the cone side. This seems unusual.

I've never seen the keys broken, ever. I would really have liked to been in on the teardown & rebuild for this one.

Ensure that you have the correct pilot bearing installed, early AX-15 transmissions use a smaller 0.590" pilot tip, while later models use a 0.750" pilot tip dimension.

Max

Click here to see all of my different albums on Photobucket.
Choose any album to see all of my pics!


Quote:
Originally Posted by UltimatE View Post
Max has a picture of every Jeep part ever made.
Quote:
Originally Posted by Benderff View Post
No one here knows what they are talking about. You should try Pirate 4x4 they will be happy to help you.

There is no situation that cannot be improved with a small but well-placed explosive.
Mean Max is offline  
post #7 of 10 Old 02-24-2013, 12:04 PM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
Quote:
Originally Posted by Mean Max View Post
The bubbling sealed bearing condition is typical.

Syncros in the AX-5 & AX-15 transmissions most commonly wear on the backside, where the keys engage, rather than on the cone side. This seems unusual.

I've never seen the keys broken, ever. I would really have liked to been in on the teardown & rebuild for this one.

Ensure that you have the correct pilot bearing installed, early AX-15 transmissions use a smaller 0.590" pilot tip, while later models use a 0.750" pilot tip dimension.

Max
I took quite a few pictures of it as I took it apart and still have all the pieces including the broken keys. PM an e-mail and I will send them to you. Too big for me to put all of them on here.

There was some light varnish on the synchro ramps of the gears, I cleaned it off with red scotchbrite.
Attached Thumbnails
AX15 before.JPG  
RenoF250 is offline  
post #8 of 10 Old 02-24-2013, 12:44 PM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
Here are some shots of the old synchros. You can see they had all worn to the point that their backs were touching. 3 and 4 are chewed up as well.
Attached Thumbnails
Old Synchros (1).JPG   Old Synchros.jpg  
RenoF250 is offline  
post #9 of 10 Old 02-24-2013, 12:48 PM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
The new synchros for 3 and 4 are different, ramped on one edge and straight on the other. Have you seen this before?
Attached Thumbnails
new synchro.JPG  
RenoF250 is offline  
post #10 of 10 Old 02-27-2013, 10:00 PM Thread Starter
RenoF250
Registered User
1985 CJ7 
 
Join Date: Sep 2011
Location: Foresthill
Posts: 2,617
I was shifting it with the case off and got 3rd synchro jammed the same way. That is a bit concerning. I hope once it is bathed in oil it does not have that problem. It is all together now. Goes through all the gears and N but 5th is a bit of a pain to go in.
RenoF250 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome