350C Brake self adjustment assembly?

[Tjgerow]

Im looking at buying a 350C dozer and am currently helping the owner install new brakes. He's in his 80's and been working on dozers a long time so I'm getting a really good education from him and all his years of experience. I've only worked on autos and my Kioti tractor.

We ran into an issue assembling the auto tensioner on the brakes. We have a service manual but it only shows a drawing of the exploded parts.

Does anyone have an actual picture of their brake auto adjusters?

Are the 350C's similar to another model I could google? I've not found many pictures of a 350C with the housing covers off. Youtube has some good videos of people working on 350B's, but nothing with 350C's that I've found yet.

Thanks,
Tom

[LeonardL]

I'm not sure if I have any pictures or not. You can try looking for 400G machines as they have the same mechanism as the 350 C & 350 D. I have never googled either one so I have no clue if anything is out there. If I find some pictures I will share them but I really don't think I do. I am curious what your issue is. If it helps both sides both right and left go together the same on both sides. You would think there would be a right and a left for the adjusters but there isn't. They both go on the same way and they both adjust or tighten clockwise on the star wheel.

[Tjgerow]

The issue is I'm not sure how the parts go together so that the adjuster will work correctly. On page 0250-6 of the technical manual it shows pin #20 and adjustment link #17. The pin has 3 places for the snap rings. I'm thinking one snap ring goes on the outside and against the Link (#18). Then the Adjustment Link, another snap ring, then the spring then the final snap ring.

The orientation of the adjustment link is also a question. I'm assuming it is supposed to click into the grooves around the adjustment nut(#3).

If that makes any sense.

[LeonardL]

Yes it does make sense and you are correct. Bear in mind that both sides, left and right will mirror each other. If that makes any sense. The only picture I found was the same one you probably have. But, your adjuster will mount the same on both brakes. As I recall the pins will be to the inside or towards the transmission housing for the right hand side and they will be towards the outside or the final drive housing for your left hand brake. I hope I don't have that backwards. It may well be flipped. But you should get the idea of what I'm saying. It's hard to explain and make any sense. I'm sorry. The exploded view of this mechanism that you're referring to is exactly how the parts assemble on both brakes. Your pins all go in place the same on both sides. I hope this makes sense. I've done a couple hundred of these and I always have to think about it before I get it right. I will dig through my pictures some more and if I come up with something I will let you know. Also don't be afraid to send a PM and we can go from there.

[Tjgerow]

Thanks for the information. I followed your description, it makes sense.

I'll be back working on the dozer Monday. Hopefully they don't have the top buttoned up yet cause I really want to make sure it's correct and take a few pics.


Regards,
Tom

[Tjgerow]

Here is a picture (I hope) of the brake assembly on the left side. Does that look assembled correctly?

[LeonardL]

Well it is mostly correct. There should be another C-clip that retains the brake adjusting lever. Notice the groove in the pin? There should be a clip for that groove and the adjuster should be held in place by that clip. Great picture by the way. I looked through my pictures and I had a lot of the older dry clutch / brake but none of the wet clutch systems.

[Tjgerow]

That's the part I was curious about. I'll be pulling it back apart if I buy the machine.

This machine is strange. The brake bands are new. They appear to have a thicker metal back than the old ones according to the owner.

On the right side the band was hitting the bottom of the case where the casting seams are. We couldn't get the brake band to rotate to align the brake anchor and struts. So we ground the seam down and smoothed out the housing. It didn't take much grinding.

The left side needed a little grinding on the seam. But the biggest issue was the band wouldn't close enough on the clutch housing to get the struts to snap in place. With the struts all the way out they measured about 1.25". With the band installed we could only get the gap to 1.375". So we ended up grinding the brake band about an 1/8 on each side, making the grooves deeper for the struts to engage in and be able to have a little play in the adjustment.

This worked fine, but dang, I hated to grind on it. The owner did some grinding and then handed me the grinder and said have at it.

The left anchor also would not drop into place from the top (the right dropped right in) . We couldn't get the front anchor pin past the lip of the case. The case had old grind marks on it where someone attempted to expand the opening at some point. We ended up taking the grinder to the side of the anchor since we didn't want to get metal in the clutch housing.

I'm learning a lot about the drive on these machines. I have had the final drive housings on and off at least three times now for various reasons.

If I end up buying the machine I think I will be pulling it apart again to thoroughly go through the specs on everything and make sure the correct length bolts are used. The owner has a bucket full of bolts he just grabs from. I've had to check the length of some because certain holes needed shorter bolts that he had in other holes. And I haven't seen a torque wrench anywhere.

Hopefully next week it will be running and I can get an idea of any other work it might need. So far I'm having fun and learning alot.

[LeonardL]

Wow! Sounds like you have had a mess. I am assuming you or the owner bought aftermarket brake bands then? Just curious. I know the Deere bands are like stupid expensive new. But!!! They will always fit and if taken care of they will last a very long time. I know of several machines that are closing in on ten thousand hours and they are still on the same bands and clutches.

I have sent a few of the OEM bands out and had them relined. So if you can get your hands on the old bands you might want to keep them. Deere in the past seemed to have a policy in the engineering department to not leave much tolerance in their housings. Just ask anyone who has ever had the pleasure of pulling an HLR out of a 400G or 450 / 550 reverser. It is next to impossible to get them out and then going back in is no better. They're funny, you get them just right and they will come out easy and the same going back in. But have them just a little bit out of sync and you can't force the things either way!! It's the kinds of things that make Christian mechanics loose their Christianity. Or at least make them have a weeks worth of repenting to do after they work on one of these. One thing is certain, you will be good at pulling a final drive on a 350 C after you're done and well versed in the clutch and brake system. As they say, hands on is the best teacher.

I hate having to grind on anything. If it went together the first time then it should go back together the second time. If things are correct you shouldn't have to grind anything. Even though those tolerances are close, all of your parts will fit.

The bolt issue you mentioned is critical in a few different places on these 350's and the 400G's. So... You will want to double check where he may have put a bolt that is too long. The brake anchor is one place and then any of the bolt holes that are drilled and tapped all the way through the housings. Depending on what may be bolted onto the rear of the machine, you can run a bolt in far enough to jam the brake band. So I would really check your bolt lengths.

Torques are always important but at least this area is a little more forgiving. As long as the bolts are tight and not jammed against something or bottomed out in the bottom of their respective holes. Again bolt length is an issue.

I may have missed it but I am curious where your located? Just your local geographic area is enough. You don't need to get specific. Just a general idea of where you're at can help in diagnosis some times. Not on this issue specifically but other things you may run into. Machinery can be subject to the climate they're being worked in.

Good luck with this and as always keep us posted on your progress and whether or not you end up buying the machine. One thing is certain, you will know what you have in the end.

[Tjgerow]

Thanks for all the info and comments. This is a great forum.

The guy working on it is pretty religious but he's dropped some colorful language a few times. It's kinda funny as it's so unexpected.

I'm glad he's letting me help as well. He's given me some good info and letting me get my hands dirty, which is fun. And hopefully I'll have a good idea of what else this machine needs once we get it together.

I'm located in central Virginia.

Tom

[CatD8RII]

Hi guys, sorry I'm a little late, this pic should show the other c-clip Leonard mentioned.

[Tjgerow]

So the "tab" goes under the adjuster nut? In my picture we have it on top of the nut, I think it was a guess. I'll definitely be pulling the covers off again to make sure these are correct.

Hopefully it'll be running this week and I can decide if I'm buying it. Kinda the devil I know at the moment, vs getting a different machine with unknown internals.

Thanks for that picture, it helps alot and I'm going to print it and add it to my manual.

Tom

[LeonardL]

Yes this is correct. The adjuster works from near the bottom of the adjusting nut and it will turn the nut clockwise to tighten as the brake band wears. I should have mentioned that earlier and maybe you would have understood it better. But you got there in the end and that's what you needed.You are good to go on this one and hopefully the other side looks just like it. I usually adjust the band up until it just begins to drag the brake drum. Then after everything is back on the machine I do the final adjusting so you have proper steering handle travel and as always the clutch releases before the brake engages. These wet systems are usually okay as long as no one has screwed with any of the other adjustments in the linkage. They can also feel a bit tight right at first. You will think the brake is engaging before the clutch releases. But... we will worry about that after you get the machine back together. Keep us posted!!

[LeonardL]

I forgot to thank Andy...CatD8RII for the picture. You did good!! I can never get pictures to load. I'm sure it's easy but for an old fart like me and my patience level I don't even try. Anyway thanks for jumping in there with a great picture showing these wet systems configuration. The tech manuals for these 350C & 350D almost appear as if Deere quit trying while in the middle of producing the thing. Pictures are worth way more than a thousand words could ever explain. Especially if I'm the one doing the talking. They opted for a drawing instead of a good picture. The 400G manuals are no better. Anyway...thanks Andy.

[CatD8RII]

Yes, just like Leonard said, the clip goes on the bottom, and will attempt to compensate for wear by tightening the nut.
When you rotate the nut you should feel and hear a click as the tab engages with the nut.

Don't feel too bad Leonard, I had to go re-read the FAQ a couple of times before getting it to work!