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reelman
08-20-2007, 10:42 PM
I have an early 80's CAT D3B dozer. It has sat a while, now I have a drive issue. This machine has the two levers and two brake pedal set up. At first I thought I had a brake holding up, but now I wonder. This is what happens, with blade up and moving forward, if I pull back left lever and apply left pedal, left track stops and I turn left, perfect. Now on the right side I pull back on lever, push brake down and slam, whole machine stops. It is almost like the lever is not disengaging the drive clutch, but the brakes are working. Both hand levers feel the same. The foot pedals are a different story. The left travels much further easily and the right has shorter travel and is much stiffer. Has anyone run into this before? Any ideas or help would be appreciated.

Construct'O
08-20-2007, 10:58 PM
Sounds like something wrong with the left brake.It should feel like the right one.When was the last time you adjusted them.

Left one should just travel the same distance as right one and be stiff feeling.The early D3 i think had some issues with the brakes.

Might want to check with the guys over on Heavy Equipment Forum.Com
Might have to get a manual for it and read up on it.Good luck.

dozerman21
08-20-2007, 11:03 PM
Welcome to the site! I have always ran, and still do, Case Power Shift transmissions that I think are similar to your Cat, at least in concept. I haven't ran a D3B though, only C and G Series Hystats.

My first thought when I read this was what you were thinking it might be. I'd guess that your brake is sticking and locking up, while the drive clutch is still engaged. We were having a similar problem with our Case 855D highlift. If you pressed the right brake all the way, it would seize up. Since yours has been sitting a while, I'd bet that's what it is. Without tearing the machine in half, we couldn't really do much with ours except spray a ton of WD-40 on the moving parts, and try to work it loose with a long pry bar. It helps. It also helps to use it once in a while, or at least move it around some. Ours sat for a long time too.

You might not get a whole lot of responses on this. Dozers aren't real popular on here, but you can definetly learn some things about a variety of different machines. Maybe Construct'O or RSG will have something to add to this. Good luck.

dozerman21
08-20-2007, 11:06 PM
Sounds like something wrong with the left brake.It should feel like the right one.When was the last time you adjusted them.

Left one should just travel the same distance as right one and be stiff feeling.The early D3 i think had some issues with the brakes.

Might want to check with the guys over on Heavy Equipment Forum.Com
Might have to get a manual for it and read up on it.Good luck.

Dang... You already snuck in there!! How's that for service!:laugh:

reelman
08-20-2007, 11:24 PM
Thanks for the input. What is the other site you refer to, heavy equipment forum.com? I have not found that, could you post a link? I did spend the afternoon spraying it with WD40. I will try some leverage tomorrow. Not a lot of external moving parts, so I have my doubts it will be that easy!

dozerman21
08-20-2007, 11:32 PM
It's not easy to get to them, but try taking the floor plate off, or whatever else that bolts on that might be in your way.

Here's the link: www.heavyequipmentforums.com

I think you might need a couple of posts before you can ask a question, or maybe it's the other way around?:confused: :)

Fieldman12
08-21-2007, 05:35 PM
Well, I am trying to remember back to my old Cat D4 days. To me if the left side works fine by itself that I dont think there is an issue there. It sounds like to me you may have some sort of internal leak. I never have had one of these apart to know if they are wet or dry clutches. I would find out what type of clucth and brakes are inside of it meaning wet or dry. I thin that is a start point. Im trying my hardest to rember the fix for this issue as I have heard of if before but I cannot for the life of me remember