400G steering concern

[cantbeatadeere]

my 91 400G has an odd steering concern when turning left. let me start with both sides are set up exactly as the manual says, I jacked the machine up and adjusted everything step by step per the shop manual. turning right is perfect but when turning left it is fine until you're having to pull extra hard like when you're on flat ground then there is a sudden grab that can be felt through the steering lever, and it stops the track - not a smooth decrease in track speed like on the right side.....any ideas or knowledge on this is appreciated.

[LeonardL]

So... Couple of questions??? And then a couple possibilities. First question...does the steering clutch release on the left? Can you feel the clutch release before the brake band grabs? One possibility is that the clutch isn't fully releasing ahead of the brake band. Make sure the adjustment is correct at the steering valve itself. You will have a rod connecting the lever to an eye bolt on the plunger or spool. There is an adjustment for that spool so it releases the clutch ahead of the brake. What I have seen is the clutch is still trying to over power the brake. Then when it finally does release it causes the brake to grab hard and cause your issue. Let's hope that is what it is.

Next question... This one is a little harder to swallow. How much of the brake adjustment stud is there threaded through the star wheel on the left side? If there is a lot of that stud sticking through the star wheel, as in an inch or more then it indicates a badly worn brake band. What happens is when the clutch releases, the band is metal to metal and it grabs the brake drum and stops it suddenly instead of gradually engaging it. These wet system brake bands are prone to wear on the top ends of the brake band and will either wear through the lining down to the metal or will tear the lining off and cause the issue you describe. Unfortunately that means a tear down and replace the brake band.

[cantbeatadeere]

Thank you Leonard for the response, the clutch does release and the track will stop on its own when jacked up just as does the right side before the band grabs....seems as thought I remember when adjusting that the left side and it required more turns on the wheel than I thought it should(going back over a year) I will pull the plugs and compare. When adjusting did not fix the issue I figured the band was the next logical step--wanted the second opinion that you provided. this dozer has only 980 hrs on it with both previous owners private use.

[LeonardL]

There are linkage issues that can cause what yours is doing as well. But it still requires going inside to find out. I have seen the main anchor stud back out of the yoke. You can't adjust the brake at all when that happens. So, I'm betting on a brake band being bad.

[cantbeatadeere]

I will take it apart this fall and get to the bottom of it --- or possibly sooner. I will post my findings.....this site is truly helpful.

[cantbeatadeere]

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COUPLE PICS OF THE TOYS!!!!!!!!

[LeonardL]

Nice!! Love the old 2520. I have a 1520 that I changed from gas to diesel. I took a 3179 engine out of a 350D and swapped everything over. Burns about a quarter of the fuel and got more HP out of it as well.

[cantbeatadeere]

LeonardL, It's looking like I am going to work on my 400 this weekend, received the new O.E band this week.....can you give me the bulk of what I will have to remove (rops, tank, ect..) or is there a shortcut you have found in your experience?? thanks.

Also I was scratching my head a little as how a wet system could have a worn band or bands. when I bought this the machine only had about 900 hrs on it (45 ish hrs a year since new) it had done a lot of setting in a shed. I got it home and realized the brakes rod/couplers attaching pins were set up solid and the brake lever would stick...I believe the guy did not realize this was happening and wore the shoes....guess I will find out.

[LeonardL]

I will send you a PM so watch for it.