955L questions before i buy

[cg3p0]

Ok i finally got around to getting up some video i had been doing of the cat. I had been messing around with the clutch filters. Ive started on the pedal linkages and adjustments already and will post some more content when im done with that.

The dust and heat arnt so bad, its the danm biting martian bugs this year that suck!

 

[Nige]

You have segmented sprockets. That'll help when you replace them - which will be soon considering that the teeth on the RH one are close to being like razors.
Carrier roller (RH) in your video is starting to wear out.
Have you noticed that the guards/covers are missing over the track tensioner/recoil springs..?
Plan on replacing the tension spring and overhauling the tensioner & recoil mechanism on the LH side SOON........They're not refered to as "Death Springs" for nothing.
Did the oil in the steering filter housings smell burned to you..? It looked awful dark.
A Parts Manual would be a good help to you if you don't have one yet. I can probably give you a link to one you can download in pdf format from Cat for about $90.

 

[cg3p0]

Yea i noticed the guards were gone, all the old cats i looked at were missing them. I might try to hunt down a new set somewhere. The oil did smell very strange to me, not sure i would describe it as burnt smelling but definatly wierd. Does that mean something?

 

[Nige]

Burned oil is usually a symptom of something gone awry in the steering system, like a clutch or a brake (or maybe the trifecta - both). Try dipping your fingers in it then take a good sniff. Any type of burned smell ought to be pretty obvious. I just caught a glimpse of the colour of the oil when you pulled the cover off the steering filter in the video. The oil in that system should be pretty much clear, not dark brown. Plan on new oil and filters as a priority, but you'll have to get the oil hot before you drain it or you won't get the contamination out of the system when you pull the plug. I'm not sure I agree with you that the filters aren't plugged just on the basis of an external visual inspection. The only way to tell is to cut the filter apart, press a section in a vice and then look for particles in the bottom of the pleats. Based on what you had on that shop towel in your video I reckon both filters are, if not plugged, at least well contaminated.

Obviously one of your first challenges is getting the machine to steer both ways, but don't lose sight of that LH recoil spring. It's nasty, and with no guard on it if something lets you it will hurl parts hundreds of yards - I kid you not. Anyone who is unfortunate enough to be hit by one of said flying parts is also going to be very dead afterwards.
https://www.heavyequipmentforums.com/threads/death-spring-removal.75004/

 

[cg3p0]

Yea your right about not knowing the condition of that filter. After seeing more about how it works now, i would hve thought both left and right cylinders would not be functioning if it was a clogged filter. Either way I will get a new filter when i change the oil. I am highly suspect of the brake band being broken. What did you make of the material i found in that screen? Do these brakes have that kind of material on the bands? Not sure if its worth doing the adjustments to the pedals until i visually confirm there is still material on the band. Unfortunatly after taking off the brake ajusting top plate and the other top plate of the clutch compartment, i still can not see down in there to tell if the brake band is still intact. That might explain the funny smelling oil and the chuncks i found in the screen though i believe.

here are some pics of what im looking at

view from the top, (front) clutch/brake top plate removed, (rear )brake adjuster plate removed


Here is looking inside that top plate, cant see the part of the brake im looking for. See the gasket material falling off, that is part of what i found in that filter screen that i thought was a seal.


this is a view from the back of the machine, i think i will have to take off the bevel gear top plate and possibly the clutch/brake top housing to see the brake band, as well as the fuel tank i think in order to see that brake

 

[cg3p0]

Oldgold69,
None of my linkages are stuck, they all appear to be working but definatly out of adjustment. The broken side goes down much further than the good side.

 

[cg3p0]

after scratching my head a while, i figured i may as well do the adjustment since it will be a lot more work to pull the tank and clutch/brake housing to look at the brake. The first step in the adjustments is tightening up the brakes. Upon tightening them i noticed that the while tightening the right brake adjuster(the side that doesnt turn) the brake makes a clicking noise as i tighten the adjuster bolt. The good side does not make that clicking noise. More confirmation something is wrong with that brake band i would say.

 

[Nige]

The material you had in your video is friction material IMO. Where it came from is another matter, but the fact that one brake is not working kinda points in that direction. I was hoping it was something external such as linkages.
The "gasket material" on the cover is worrying. That cover is supposed to have a gasket on it, not gasket maker. If someone went in there and cut that corner (not replacing a genuine gasket that was obviously broken) then what other corners did they cut while they were in there..?

I think plan on a complete teardown of the steering clutches and brakes on both sides sooner rather than later, hopefully before the brake drum on the RH side is badly damaged. I would hold off on the oil and filters until you are ready to tear into the machine, then drain the oil, do the necessary repairs, change filters and fill with new oil all at the same time.
Offroad Equipment - www.offroadeq.com/ is a good source of parts for your machine. They have both OEM and non-OEM parts available.

 

[Nige]

Yea i noticed the guards were gone, all the old cats i looked at were missing them. I might try to hunt down a new set somewhere. The oil did smell very strange to me, not sure i would describe it as burnt smelling but definatly wierd. Does that mean something?

When you say "smelled weird" did it by any chance smell somewhat of sulphur..?

 

[cg3p0]

I would say it smells more burnt than like sulphur. You think i have to completely tear down all the clutch plates too? I could not just take the drum assembly out and replace just the break pad if that is the only thing wrong?


Im going to get the pedals back together and move the machine out in the field so i can get my tractor around it to lift off the gas tank and whatever other heavy stuff that needs to come off. Ive been looking through the manual trying to figure out just how much stuff needs to come off. Im thinking for sure gas tank. All the info in the manual seems to be in the section of the power train disassyembly and assembly.

Looks like the filter and steering booster cover and the steering booster need to come off. Then the steering clutch case cover comes off.




From there im trying to figure out if i can just slip off the brake drum or breakdrum/clutch assymbly without removing the entire bevel gear shaft with it. Pictures show the entire thing being removed. Im just worried about lining up the bevel gear back correctly upon reassembly, seems complicated.



Would be nice if there was a bit more detail on all these procedures.

 

[Nige]

The reason I asked did the oil smell of sulphur was just on the off-chance that someone had filled the case with an EP Gear Oil instead of the TO-4 Powertrain oil that should be in there. EP oil smells of sulphur and does weird things to all sorts of things, including brake & clutch friction materials. If you have the bevel shaft out it's a simple matter to open the clutches up.

Is it worth calling the person you bought it from and ask what oil they put in it the last time it was changed..?

 

[Welder Dave]

That's a little odd the 955 uses a gasket and a 931B calls for silicon gasket maker on the clutch covers.

 

[cg3p0]

Im pretty sure he was using the right oil, he was telling me about it and i know he was getting it from one of the local equipment shops and he also had the maintainence manual with the oil specs in it, i think he said he was using sae 30. I could call him if needed, he was a nice guy.

About that gasket material, looking closer at it, it does have the actual gasket but it looks like the gasket was glued on with some kind of gasket maker.

It does look like it would be easy to pull everything off with the whole bevel shaft out, but will it go right back in without having to do all that backlash adjustment and bearing shimming and whatnot?

 

[Nige]

Provided that no bearings or gears are replaced, I would say that no bearing/backlash adjustments would be required, although my mate TC Tractors might disagree with me.
You could consider removing & reinstalling the shaft assembly yourself, then have a local shop pull the clutches off for you and press them back on afterwards. TBH going that far into the asembly there would always be the question mark over what state the clutches were in.

A test for the steering clutches could be done if you have a level grass area 50+ yards long. Drive the machine in a straight line and mark where the tracks end up. Reverse back to the starting point. Travel forward a 2nd time and press one steering pedal just far enough to release the steering clutch on that side. The machine should turn in somewhat of a slow curve. Again mark where the tracks end up and get back to the start point. Repeat the test using the steering clutch on the other side. Mark where the machine ends up and compare the "deviation" measurements. If they are pretty much the same then the clutches are probably OK.

 

[cg3p0]

Ok i did the test. When slightly pushing the left pedal, the one that works, the machine steers off to the left a good amount. When slightly pressing the right pedal, the broken side, the machine just goes straight just like the first run without pushing the pedals.

I followed this up with another test i thought of. I burried the bucket in the ground and put it in 1st gear and opened up the throttle to spin the tracks. I then slightly pressed the left pedal, left track stopped spinning. Then i slightly pressed the right pedal, right track kept on spinning.

What i think has happened is that something happened to cause the right clutch to not disengage(still undetermined). The previous owner at that point had continued to use the machine slamming on the break while the clutch was still engaged causing it to eventually blow out the break pad.

Thinking i need to start tinkering with the steering booster clutch releaser thingy on the right side, or possibly do an oil pressure test. What do you guys think?

 

[cg3p0]

 

[Nige]

It sounds to me as though the right steering clutch is not releasing, and as you rightly point out the previous owner probably burned the brake out trying to get it to work.

If you find nothing definitive on the steering clutch booster pressure test it's looking increasingly likely that the right steering clutch may have to be disassembled to find out why it's not releasing.

 

[cg3p0]

Trying to hunt down a cheap test kit. Would the pressure test show if the seals are blown in the steering booster on that right side? Would like to confirm the right booster hyduaulic is operating before taking apart the clutch plates. Wonder if there is a way to take off the steering booster and cover and filter assembely and suspend it above the clutch housing and press the pedals to see if both booster cylinders are opperating?

 

[cg3p0]

I went out to look through those top clutch covers to see if i could see the clutch release mechanism moving while pushing the pedal with the machine on. I could not see them move, but i could hear the hydraulic oil going through the booster. Upon releasing the pedal on the good side i could hear the distinct noise of fluid flow being shut off. The bad side i could not hear anything when releasing the pedal. Im thinking there must be a seal blown out or something on that right booster side.

 

[cg3p0]

Ive been busy digging into things, i got everything off all the way to the steering booster so now i can take a look at things. The break pad appears to still be intact from what i can tell. However something is not right with the lever that the steering booster pushes on. Look how much further away the lever on the right is. There is so much more play on that side, just feels loose when i move it. What could that mean? So maybe the right steering booser seals are still fine, it just wasnt making any sound because it wasnt getting any back pressure from the clutch springs?