Submitted by Deas Plant. www.acmoc.org/bb/archive/index.php/t-13739.html?

Hi, B4D2.
Thank you, Bruce. This facility has been suggested quite a few times in the past as there are new people coming on to ACMOC all the time with similar problems on similar machines and the information is there for all to see in earlier posts, trouble being that the 'newbies' don't know that and it can also be a PITA trolling back through the thousands upon thousands of posts to find what you want.

Next question: Is it possible to have folders - or threads - within a thread for this particular thread so that specific machine-related maintenance information can be placed in the appropriate folder within the thread. F'rinstance, we seem to get a LOT of questions relating to D2's, probably 'cos they are relatively common and cheap to buy, so it would be handy to have a section specifically for D2's. Is that possible?

If the above is possible, it would then be up to anybody who wishes to post such information to find the appropriate place to post it if they want others to be able to find it easily.

Just me musing.

The past few years we have been discussing a spot here on the Forum to store all the Tech Sheets that our highly experienced, and generous members like "Edb" and "Old Magnet" regularly post for our benefit, and B4D2 indicated a few months back that when the ACMOC computer system got upgraded this year that a proper place would be created, or an attempt would be made where these scans would be stored and easily accessed, such as within a separate "Library", is this the way it is now intended for those scans to be stored from this point on because I was assuming / hoping they would not be buried under or amongst potentially hundreds of pages of chit chat over the next 10-20 years, because those technical questions can and will still be asked in the Discussion section.

We all agree the current Search Function within the Forum can leave us very frustrated even when searching for basic info, it is easy to spend a hour or more looking at 30 pages of old posts and not find the basic info you need, so I was hoping the Caterpillar Tech. Sheet scans might find their own safe spot for members to use, and be possibly stored in folders either by machine such as D2, D3, D4 etc, or by topic, such as "Head Repairs", or "Final Drives", or "Clutches" or "Pilot Motor Carburetors" for example.

From memory I offered to throw some money into a hat to kick start the project and others soon generously followed, as B4D2 had suggested that funding this new "Library" might be a issue within the computer upgrade budget, both financially and with limited Volunteer hours, so I'm just hoping we can do this once and do it right, because I know for a fact guys like "Edb" and "Old Magnet" have far better things to do with their lives than re-post the same Tech Sheet scans every year or 18 months, and I'm extremely worried we have already lost forever a lot of valuable information as older posts including Tech Sheet attachments from Old Magnet and Edb were deleted by them as they exceeded their stored info allowance over the years.
Regards
Mike

Hi, Mike Meyer.
I agree totally with all that you have said. I don't see this particular thread as the be-all-and-end-all of the tech. info. storage that we need on this forum but I do see it as a starting point. Personally, I would like to see this thread indexed by machine model but even that could create a fair bit if extra work for somebody with some computer skills AND some knowledge of the various Cat models. I don't envisage that the indexing would be done by serial number prefixes, only by model designations such as D2, D4, D6, etc..

I do have a fair collection of the tech sheets saved amongst my collection of bits and pieces and can either post them on this thread of send them to Adco for posting where best suited. What I DON'T have is all the wonderful knowledge shared by our resident 'Wise Men Of Caterpillar' and dredging all of that out of the archives would indeed be a daunting task.

BTW, if you care to drop me an e-mail with your snail mail address, I will copy all the information, photos, data, etc., that I currently have onto a remote hard drive and send it to you. If you wish to spring for the cost of the remote hard drive that would be appreciated but not NECESSARY.

With that said, I really think that your post and any responses to it ought to have been under their own thread out on the main BB for ALL to see.

Just my 0.02.

Mike, The current merging of databases is underway with our server provider. Also included in the upgrades is a larger server to help accommodate some of the things you have mentioned. Peter also started another thread recently that had some other fine ideas. Once we get the multiple databases sorted out and the new server on line, we should be able to better identify who is a paid ACMOC member and delineate the site to allow for a dedicated archives section (or some other title thereof).

I have also extracted the previous "RD 6" conversation and started a new thread in the "discussion" section, so that info isn't lost or deleted. I will come back later and delete or merge these comments to keep this thread clean and headed in it's intended direction.

Thanks.

"B4D2" wrote:

Mike, The current merging of databases is underway with our server provider. Also included in the upgrades is a larger server to help accommodate some of the things you have mentioned. Peter also started another thread recently that had some other fine ideas. Once we get the multiple databases sorted out and the new server on line, we should be able to better identify who is a paid ACMOC member and delineate the site to allow for a dedicated archives section (or some other title thereof).

I have also extracted the previous "RD 6" conversation and started a new thread in the "discussion" section, so that info isn't lost or deleted. I will come back later and delete or merge these comments to keep this thread clean and headed in it's intended direction.

Thanks.

The trouble with editing your comment is it shows that everyone has read it. Sorry.

Hi Folks.
Here is a video clip on YouTube showing some of the ins and outs of working on a Cat rear-mounted DD CCU

Hope this helps.

Hi, Folks.

Adjustment instructions for pre-hydraulic Caterpillar gear-controlled graders.

Here are the 'destructions' for adjusting blade lift controls on older Cat gear-controlled graders.

Firstly, for those looking to achieve a quick fix for worn dog clutches in the control box itself, there AIN'T one. If you want to restore your dog clutches to like-new condition, you need to do one of two things:

a. Buy new ones - 100% reliable.

b. Have them rebuilt and ground back to NEW specs - less reliable as you need first to get hold of the technical data relating to correct pitches, etc., then find an engineering shop that can do it properly.

Some people try grinding them back with an angle grinder. This MAY(????) make an improvement but will NOT return them to new condition.

You can also do a switch-around of the dog clutches in the control box so that you end up with less worn clutches on the blade lift control shafts. This DOES take a bit of brain work as you MUST keep correct track of which clutches are turning which way to do whatever it is that they do so that you do get the less worn faces doing the work by facing toward the rotation direction of each shaft. Remember that the rotation direction of each shaft is the opposite of its neighbors on either side. The only ones that you can't switch are the circle reverse pair 'cos they have the bevel gears which drive all the rest from the vertical input shaft.

The output shafts from the control box, are held (more or less, depending on wear) firmly in place when the control lever is released by the "combination shifter fork and brake", which is inside the power control box (the big housing in front of your knees when sitting in the seat that has all the control levers attached to it).

There are two brake plates, which are contained within the shifter fork itself, and a HEAP of small coil springs that push these two brake plates apart when the control lever returns to the released position. This holds the control output shaft in a "braked" position, when the control lever isn't being pushed or pulled.

For some strange reason(????), these brake plates wear after a lot work and/or the coil springs weaken, causing the braking action to weaken allowing the control shafts to turn when load is applied to the other end of the drive-line. All the control levers and drive shafts use the same "combination shifter fork and brake", so you may be able to swap the various shifter fork and brake mechanisms to other positions, and replace the more used and worn ones with less-worn ones, as a "quick fix". Failing that, you will need to dismantle the shifter fork and brake mechanism and replace the springs and possibly the brake plates, with better, or new ones.

I have never seen a 70D Cat 12E as they were American-built. We had the 17K DowNunder which was the DowNunder-built equivalent of the 70D/71D while the earlier 99E was the U.S. equivalent of the DowNunder 21F Cat 12E The later 21F/99E machines and the 17K/70D machines had a small brake arrangement on the front of the blade lift output shaft in front of the control box. It IS possible to have this brake adjusted too tight. So long as the linings are in reasonable condition, these brakes gave very little trouble, at least in my experience.

First step for the rest of the adjustments - remove the inspection plugs on top of each Hi-lift gear case - the big round cases on each side of the front face of the cab. Then loosen the clamp bolts on the lift arms at the front ends of the lift shafts and remove the keys from the blade lift arms. Now slowly rotate the hi-lift gear inspecting it as it turns to find the least worn section which will be around 1/3 of its total circumference. When you have found the least worn section, which should be at the top if you are looking at that section, mark the top of the lift shaft and turn that mark to the bottom. This should leave you with a keyway facing pretty much horizontally outward ready to accept the lift arm key again.

When the mark is at the bottom, replace the key in the lift arm in the nearest keyway that lines up - there should be 3 keyways in the shaft - tighten the clamp bolts and replace the inspection plug in the top of the gear case.

Second step - locate the blade lift pinion at the bottom of the Hi-lift gear case - it is the smaller round part of the Hi-lift gear case running across the bottom of the main case. In most models of Cat grader with the gear lift system, there is a large adjusting screw in the outboard end of the pinion gear case. This adjusting screw has a lock nut on it. With the blade lifted SLIGHTLY, loosen the locking nut and turn the adjusting screw in until it starts to become firm - NOT DEAD TIGHT - and re-tighten the locking nut making sure that the adjusting screw DOES NOT turn as you tighten the lock nut.

When you have the lock nut tightened, it is a good idea to start the machine and test the controls as tightening the lock nut can change the adjustment on the screw even though the screw may not have moved during the tightening. If this happens, it is usually due to worn threads. A bit of fiddling may be required to achieve the best adjustment

(I found that a home-made wrench made from 1 1/2” x ¼” flat bar bent in an 'L' shape with the leg of the 'L' only about 1” long and made to fit the slot in the adjusting screw was a handy tool to have around the old Cat 12's.)

When you have done both sides, test the controls by raising and lowering the blade several times, including applying down pressure on the blade. If you have done everything correctly, the controls ought to be a little easier. If the controls got tighter, the most likely cause is that you have over-tightened the pinion adjustment. Remember, I said, 'NOT DEAD TIGHT'.

(I have encountered a couple of older Cat 12's that did not have this pinion adjustment. I have since been told by EDB that these older machines had shims under the plate that could be removed to tighten up the pinion adjustment.)

The Hi-lift gears are replaceable. They are usually made from aluminium - or brass in earlier machines - so that they wear out before the steel pinion gear that drives them. To replace them, you need to disconnect the drive shafts from the control box where it comes through the front of the cab. This involves removing the gear from the front end of that shaft through the inspection plug hole.

Then unbolt the Hi-lift gear cases from the front of the cab and the bearing mounts from the mounting arms at the front end of the lift shafts and slide the gear cases forward to allow access to the bolts holding the Hi-lift gears to the flange on the end of the lift shaft. It does help if you have a small crane or a block and tackle to take the weight of the gear case and shaft as you slide it forward.

As with any repair, it also helps if you have a workshop manual handy. And, if it was me doing it, I'd be checking the pinion gear and bearings and whatever else I could get at before I put it all back together.

There is also adjustment for circle clearance - shims under the circle carriers - and location - set screws to adjust the carriers in or out. Be careful when adjusting these as circles tend to wear unevenly and you could make some tight places if you get too carried away here. If the circle carriers are excessively worn, they can be re-built either by welding some thin plate - say 1/8" - on them or by re-building with weld metal. I prefer welding on some thin plate as it is usually unnecessary to grind off the finished surface. You may then need some shims to maintain clearance.

Shims were also included ex-factory in the various ball joints in the blade lift, side shift and scarifier lift and can be removed to help reduce slack in these areas - if there are any left. If not, the cups can be ground as a rough means of tightening them - you may need some shims after you have ground the cups if you get too carried away with the grinding.

A couple more adjustment tips. There WERE also shims built into the mounting of the side-shift gearbox to adjust the meshing of the side-shift pinion gear with the side-shift slide. As well, there were shims between the two halves of the side-shift slide to adjust for wear on the slide guide. Be a little careful with both of these as there is almost always more wear toward the middle of the side-shift slide and you don't need things so tight that they begin to jam up.

You could also adjust the lean wheel rack down on the lean wheel top brace to cater for wear between the rack and the pinion. This is done by ADDING shims, NOT by taking them out. This is the ONLY adjustment on these machines where you ADD shims to compensate for wear.

When those old girls came new fresh out of the factory, they had JUST enough clearance in the ball joints to allow them to turn without binding, so little that you could not see it. The blade lift gears all meshed perfectly and the dog clutches in the control box ONLY kicked back under EXTREME load - you were more likely to shear a shear pin in the vertical drive shaft to the control box. The front lean wheels did NOT flop all over the place and the steering DIDN'T have a turn and a half slack. LOL.

I believe there is a ‘German’ word to describe how tight they were.

"SCHNIEZENTITE".

From there it was a long, SLOW progression to the 'knuckle-buster' controls, 3 or 4 inches of 'stump-jump’ in the blade and a severe case of wanderlust in the front end. The good part about it was that it DID take a long time and a LOT of work to wear much slack into them.

The more of that slack you can remove without causing anything to bind up, the better.



You have a wonderful day. Best wishes.

Deas Plant.

"B4D2" wrote:

Upon suggestion from Deas, here is a locale to post detailed maintenance procedures. It will be a stuck thread but open for additions.

I have a D4D dozer that the breaks are not working are they in fluid or dry. Vin is D4D 82J3323 I have no idea what I am doing I need help in finding out what is wrong ?

When you need to pull Master Link Pins.
A trick that seems to work is to remove the cork or broken bolt from the Taper Plug whichever the case maybe(I had both).
Clean the threads with a bottoming tap.
Flush with loose juice(I use KROIL).
Blow it out with air.
Take your Gas Ax, aim it into the hole of the plug to heat it.
Squirt loose juice on it to cool it rapidly.
Use a Socket large enough to sit on the Master Pin.
Screw a NEW Grade 8 bolt that is long enough to use most of the threads in the hole with a couple of washers into the Plug.
Turn it out, if it gets tight, hit the wrench with a hammer to help it jar as it turns into the plug.
Heat around the base of the socket if necessary to expand the Master Pin.

Heating the plug, then rapidly cooling it, makes it shrink, heating the pin with the bolt tension on it expands the hole diameter of the pin.

You can feel it pull up tight, then go a little more you will feel the plug give as it moves.
I had enough washers on to have at least 60% thread engagement.

This worked for me!