Steering on a 350c

[Mbailey]

Hi all, my 2nd post in a couple of weeks here. On my 350c I completely redid the fuel system,welded up a lot of cracked welds in places, redid the radiator, cleaned the tank, new fuel filter setup, greased everything,changed all fluids and filters plus lots more.
I have been using the machine and it has been running great, lots of power. What I have a question about is the steering. In forward the machine steers with the tap of a finger and used to do close to the same in reverse. As I have been using it the reverse steering seems to be slowly but surely disappearing.
If you get the machine up on a high point in the center of the tracks it will still pivot around in reverse but on flat ground even in loose soil it will only slowly pivot with quite a bit of pressure on the handles, sometimes not at all. Again forward it steers with the tap of a finger. I notice the right handle will move back a long ways further than the left which steers better.
With the amount of knowledge on here I was wondering if someone had an idea to point me in a direction to look. Brake adjustment? Hydraulics? I am getting the manual out, but figured I would tap into everyone’s expertise to make it quicker. Thanks in advance for any help - Mark

[Mbailey]

Sorry for the double post I am trying to figure how to delete one

[Jim B]

Good morning,

350C has wet steering clutches and brakes. The first step is to do a complete adjustment of both steering valves, clutches and the brakes; step by step as given in the manual. Possible adjustment issues need to be eliminated or ruled out before going deeper and doing it by the book is the way to do that. I never heard people had much luck trying to shortcut the proper procedure, in the end.

Do the adjustment as the levers should be actuating the clutches and brakes in the same relative positions, when you apply the same force to each lever. If this doesn't cure the problem you may want to consider doing the reverser pressure checks. Some of your description sounds to me like you could be loosing the reverser's reverse clutch.
Jim

[Mbailey]

Thanks I greatly appreciate it. I kind of figured I would be heading in that direction and that reinforces that’s the right way to go. I was in the back of my mind hoping for simple but not really expecting it.

[Mbailey]

Jim, A question just popped into my head. When you said it sounds like a possible loss of the reverser clutches how would that affect the steering? The machine will climb anything and pull hard in reverse. I would think if the clutches were starting to go I would be losing power in reverse. I was guessing a possible hydraulic pressure adjustment not dumping pressure off the clutch packs or a brake problem, causing a steering issue. As I am new to this machine and have just started looking into it, I may be drawing wrong conclusions about how things work with the wet clutches. - Thanks Mark

[Jim B]

If it is pulling in reverse ok it wouldn't be the reverser. The way I read your description was in error. When you said it would pivot if centered on a high point, and sometimes not at all, I took it as the crawler stopped moving when the tracks in full contact. Sorry, My error.

[Mbailey]

Not a problem, I appreciate any input, probably my wording as much as anything. So yes it is strong in forward and reverse. Just does not want to steer in reverse but is fine in forward. So was thinking brake adjustment or a possible hydraulic hangup I am guessing possibly a valve issue but will look into it more.
I have to find another manual. The guy who I bought it from gave me service manuals, parts book and operating manual, unfortunately the service manual is for the straight 350 with the dry clutches so it’s fine for a lot of the machine but not the clutch and other adjustments.

[Jim B]

Call or email Lavoy. I believe he can get you the right manuals. TM1115 is the part number for the 350C Technical Manual and OMT79469 is the latest Operator's manual. There were other Operator Manual numbers as you will find in the list posted on the FAQ Board. http://www.jdcrawlers.com/messageboard/ ... =2&t=10109

[Mbailey]

My cousin dug up my uncles manuals, almost the identical machine he had for logging out of a dusty attic. So I now have a 350c manual. I am guessing something broke in the brake system as the right hand lever will move full stroke backwards with no resistance while the left one engages about 1/2 way back. I am pulling the tank and the covers to take a look after this hurricane passes by.
I read on here about some part in the brake system that always breaks that Lavoy possibly had a replacement for but that may be something else. I won’t know till I get inside.

[LeonardL]

I'm just now seeing this post, so sorry for the late response. Before you get too involved by taking this machine apart you want to check the linkage inside the clutch / brake housing. The linkages for wet clutch / brakes on 350C, D and the 400G can break over center and cause your issue. There should be a section in your manual that tells you about this and what to do about it. I usually just take the plug out of the top of the clutch housings and poke around with a screw driver to see if the linkage will pop back forward.

In any case it will be the adjustment of the brake band and or the set screw located at the back of the clutch housing that causes this. This set screw sets this break over point. Basically all you do is back this screw out and pull the steering lever until the linkage breaks over center and then screw it in just far enough to push the linkage back past the break over point. Then lock the screw in place with the jam nut. Your brake band adjustments can then be set to specs.

If this doesn't help your issue then you may very well have something broken or has come undone. These brake bands are noted for breaking the actuator dogs off of the bands or just breaking the entire end off of the brake band. They are a hardened steel band that can and will break.

As always, check with Lavoy for your parts if you need any and I hope this helps a bit. Good luck with your machine!!