Good morning, This is my first post but I have been reading and following many different threads. I have searched this site and the internet for info on separating a Cat 730, with no luck. S/n AGF 0366. I am new to the ADT world. I was able to pick this one up at a local auction for a fair price. As we were operating it you could see some movement in the bottom hitch pin. You can Occasionally Feel the slop in the cab. So I’m trying to gather as much info on the task of separating and replacing the pin, bearing and seals ourself, or should I take it to the dealer. We have the equipment and tools to service our full fleet of equipment . This is just a new task. Also the operator complains about the ride being rough. Would this pin have something to do with that. Any help or advice would be greatly appreciated.
Is your problem in the hitch itself or is it in the spherical bearing in the A-frame that mounts on the bottom of the lower hitch..? Section A-A in the illustration below, the spherical bearing #1 mounts in a tapered sleeve #5. TBH in our artics this is the most common area to get play rather than the hitch itself. Take a look to see whether or not the remote grease line for the spherical bearing is actually in one piece, they are usually bust which leads to bearing failure if not spotted. Cross your fingers that the worn bearing hasn't egged out the bore in the suspension frame #4. Determining where the play is will be a key factor in figuring out what is the correct procedure to do the repair.
On a side note I had an '01 725 and the wiring harness, I don't remember if it was the main one, going from the engine compartment through the cab was problematic. Owned the truck for 3 years and replaced it twice. It's been so long I forgot what the actual failure was. Had a new '07 725 on lease for 2 years and never had an issue with the same harness. BTW - Nige is the man to help you through this. Welcome to the Forums!
The bottom pin has a taper on both ends. The upper taper fits in the machine frame, the lower taper fits in the spherical bearing in the A frame. Try to work out if the movement is in the lower bearing/taper/A frame or in the upper portion. If you have movement in the A frame part, no biggie. If you have movement in the pin to frame interface, yes biggie. Either way you should get it fixed sooner rather than later. Rough ride. Check the nitrogen pressure in the front suspension cylinders.
Wow I don’t know why it took me so long to post. You all have posted and shared great knowledge in such a short amount of time. I really appreciate that. Cm1995- about your wire harness. I am guessing that was common with these machines because my truck has a new wire harness on it and I believe a new ecm. I noticed how new the wires were when I first popped the hood. We just finished our job with it and we will be fixing it ASAP. Also how would I check the nitrogen levels in the front cylinders? Nige/ Cmark- thank you for such great replies. The play that I can visibly see is between the pin and the A frame. Meaning, when we put it in gear and move forward a touch. The A frame will move forward till it touches the pin. You mention about edging out the bore. I know if it did then I would have to get it lined bored. Is there a certain amount of movement when you know it will need to be line bored? When you put it in gear you have about 1/2 inch of movement .
If you have 1/2" play in the A frame bearing you need to get it fixed. In time the banging will loosen the upper taper and then you have a whole new set of problems. If the A frame bore is damaged then it's easiest to take the A frame to a machine shop for boring and sleeving. Each front suspension cylinder has its own separate accumulator. If you don't have nitrogen charging equipment you will need to find somebody who has to check the pressure. The ride height is then adjusted hydraulically using the two valves under the access covers.
Sounds like you need to drop the A-Frame ASAP and survey the damage. Be careful, it's a tad on the heavy side but comes out easily enough especially with a worn bearing. An oval bore is a possibility, not guaranteed. The ones I've seen failed in the bearing itself and ended up replacing the bearing and the tapered sleeve as well as new hardware and other bits & bobs. Generally the seal #6 and the three bolts/washers #14, & #18. As I said before, check the grease line to that bearing, every one that I've seen within the past 2-3 years that failed the shperical bearing also had a busted grease line, and of course no-one ever gets down under the machine to check that the grease is going where it should be when they pump the grease into the fitting. While you're into the A-Frame and front axle I would suggest you replace the rubber bushes in the transverse link #9 on the LH side of the illustration above. Don't do those bushes until you have the A-frame back in place though, the front axle could get a bit "sloppy"...... A comment about front suspension. It's also important to have the correct amount of oil in the unit, so if one or both of your units have signs of external oil leaks then they probably need to come off and be rebuilt, hopefully just with new seals.
Attached is the part diagram that I got from my dealer. I was thinking that I needed to replace the parts is part “B” of the diagram. But from what we talked about that would be wrong. I need the parts to rebuild the A frame. Am I following correctly ?
Everything revolves around the bottom of the pin marked B in your illustration above. That is where the tapered sleeve #5 in my illustration above mounts. IF the taper on the bottom of the pin is still good then you will not need to split the front and rear frames to get into the hitch bearings that are shown in your illustration from the dealer. If it was mine I would remove the A-Frame first (because you already know that you have 1/2” of movement in the A-frame bearing, so it has to be fixed) and then try jacking somewhere under the frame to see whether or not there is movement in the hitch bearings. Personally I wouldn’t go into the hitch if it didn’t need it. I’ll see if I can post up a better parts drawing to make it easier to understand. A question. How many total hours does the truck have on it right now.?
Here's a better Parts List of the Oscillating Hitch Gp with Part Numbers. Pin #10 is the one where the A-Frame beaaring/taper sleeve mount.
Nige, thank you for that better drawing. To answer your question about the hours. It has 13k hours on it. So as soon as it gets to the shop, we will drop the A frame and hope that the bore hasn’t been damaged. Using the drawing that you last posted which parts should I go ahead and buy? I know that is a loaded question with out knowing the damage. I don’t believe there is any movement in the Hitch bearings I am cofindent that it is all in the A frame. Someone told me if you lift the bed all the way up and you feel the nose of the cab go down then you know your bearing in the hitch are in need of being replaced. I tried his idea and I felt no dip in the nose of the truck. Does that hold any truck?
To confirm it's all in the A-Frame I would still remove it first then put a jack under the nose end of the front chassis and slowly raise it while someone observes the hitch pins and bearings. What you've been told is probably right but if the bearings are only just starting to wear you will likely not feel it from the operator seat, you need to be watching the hitch closely while someone else operates a jack. I've uploaded the file that the illustration in post #2 came from. IMO lines 1, 4, & 5 you will definitely need. Lines 14 and 18 (3 of each) you might need depending on what the existing hardware that holds the spherical bearing in place looks like when you pull everything apart. Line 9A are the spherical bearings for the transverse link I referred to in post #7. Oh, and here are the A-Frame removal instructions. I guarantee you won't have to do Steps 7, 8, & 11 because the bearing will be so loose you'll be fighting to stop the A-Frame failling off when you loosen the three bolts that hold the retainer plate on.
Mr.nige, I am so grateful for you. Can I just get you to come to the shop while I do this? Lol. I guess I will start order these parts and as soon as I can I’ll start taking that A frame out. You have really went beyond the norm to help me. I know for a fact that we can fix this problem now.
Mr. Nige So we have started working on this ADT. The front cross member came out fine. But going to unbolt the A frame is when problems started to happen. I followed the directions that you provided me with. When we took the last two bolts out on the right hand side the whole tractor shifted. The axle ended up rolling. It pulled the drive shaft apart and is putting stress on the suspension Cylinders. Well we stabilized it as is then continued to take the A frame off. I took the 3 bolts off the bottom pin which is supposed to retain a washer but I couldn’t find a washer. So far this project has been overwhelming to say the least. Espically with this being my first rodeo.
That doesn't sound right. When following Nige's instructions, how exactly did you go about ""Start By: A. Remove the stabilizer rod for the front axle. Refer to Disassembly and Assembly, "Front Axle Stabilizer Rod - Remove"." ?
A-“Bait up” front axle with wood B- support up A- frame C - remove the cross member starting with the side that consist the bracket D- drop crossmember E- start removing A frame bolts on the left hand side- no movement F- start removing right hand side A frame bolts . Bottom 2 came out easily with the 3/4 impact. But the top two wouldn’t budge with the 3/4. Pull out the 1” impact. The top bolts start to come out but the axle is rolling forward. The truck is not moving just the axle. Thank you cmark. Hopefully this will clarify.
I’ll be honest I would’ve chocked both sides of the front wheels before starting to unbolt stuff but I understand that it’s not standard practice for a lot of mechanics.
Do you think we have messed something up by allowing the axle to roll forward.
Difficult to know without photos. Here is what Cmark was referring to when he asked about the removal of the Stabilizer Link.
So after reviewing the last posted article about the stabilizer rob. We followed all the directions other than bracing the front of the machine with jack stands
So I guess we are going to wrap a come a long around the axle and try to pull it back in place. We screwed up by not bracing the front of machine and chocking the wheels first
If you don't have the front of the machine supported on stands and all the pressure removed from the suspension struts, you're not going to be able to move the axle with the precision you need and frankly, the machine isn't safe to be under.
I would completely agree about it not being stable enough to be under so after the fact we lifted the front of the machine up and placed blocks underneath it
That's good. Are you familiar with the procedure for releasing the pressure from the suspension cylinders?
No cmark I am not. Can you explain
Each fender has an inspection hatch inside which you will find two hand-valves. One valve lowers the suspension, one valve raises it. To raise, you need the engine running. To lower the engine can be stopped or running. When you have finished the job the suspension needs to be set at the correct height. Attached instructions.
Good evening, After another day of working on the machine. We are still not successful on dropping the A-frame. We have followed the instructions to a T. We just can’t not get the bearing to come off the pin in the the A frame. We have tried hammering, prying and using a jack to pull it off. We built an object with a steel plates, rods and a jack. 25 ton jack wouldn’t budge anything. We ended up bending our steel plates. So another day down and still not much progress. We did get the axle to roll back a little bit with a come a long. But we didn’t spend much time on that since we still need to drop the A frame. Being the first time working on a ADT I must have picked the worst thing to work on.
I've got the puller for the 740 in my workshop. I'll take a photo of it. It may give you some direction.
Thank you that would amazing. I’m reading the article you posted about the suspension height. I can’t measurement that would be the correct height? It says it’s differnt for every machine but doesn’t tell you what it should be.
It's on the last page. Raise the suspension all the way, measure dimension A and subtract 1.38". Shoot for this dimension on both sides. The long-winded explanation is trying to explain that if you try to achieve minus 1.38" in one go it won't work, because as you lower one side, dimension A at the other fender will increase due to the body pivoting at the suspension cylinder.
Ok now that makes more sense to me. Thank you for clarifying. Ok so your puller bolts to the A frame and you use the center bolt to push against the pin. That’s a nice set up. Can I borrow it tommorow ? Haha.. I might end up trying to build something like that.
Lol. If you were within shouting distance you could certainly borrow it. This is for a 740, not a 730 but the principle should be the same.
Actually I would cautiously state that it should also work on your 730. Cat part numbers are 2175919 and 5P5264.
Good day gentlemen, So hallelujah!! We made progress today!! We finally got the A Frame to fall from the center pin. The bearing had a lot of slop in it. But thank heavens it has not wore through the outer race to hurt the bore size. The tapered sleeve came off the pin with a few licks with the hammer and the bearing was worked out with a punch and hammer. After cleaning the bore we put the new bearing in and beat it down to position. Then we beat the tamper sleeve in the bearing. So now we have to reassemble the A frame and put new parts in the stabilizer cross bar and install.
Always nice to hear a success story. I'll be honest and say that with the amount of "slop" you appeared to be describing in your OP I confidently expected that bearing (and the A Frame) to fall off. Question: On your truck is that bearing greased via a remote grease line or does it have a zerk right on the A-Frame.? If it is a remote grease line you should check that it has not rubbed through somewhere, They generally do. Before reassembly do you fancy putting a jack under the hitch and carefully moving it up and down a hair to check for movement in the hitch bearings..? That's probably the best time to do it. Refer to my post #9 on Page 1.
Mr. Nige The grease has a remote line. I checked the grease line and it did not have a leak. I cleaned the inside of the fitting that screws into the head of the A frame to assure it wasn’t clogged. But I noticed on the old bearing that the grease groove. was packed with old, dry , hard grease on one half of the bearing. So the bearing was only getting grease to one half of the bearing. Also yes sir we will be checking the hitch bearings like you mention in a previous post.
Mr. Nige As stated before, with your wisdom and help we were able to get the truck up and running. It has been running like a top. We have done a full service on it and all fluids look good. The transmission fluid looked fantastic, I firmly believe that this truck has had a rebuilt transmission. I can tell the cab has been tilted and a few other things that make believe it’s been worked on. But I come to you ( or anyone else) today to seek information on the Diff lock. (The button on the floor board) you press that button and hold it with your foot but you don’t feel or see any difference. With all the rain we have been getting, the truck gets stuck a lot more than we would like. I would imagine you would feel a slight bump or hear something with the switch engaged. Am I wrong? Or how can I test that switch is working?
The floor switch engages the inter axle lock inside the transfer box. To engage the diff locks both the diff lock switch on the dash must be turned on and the floor switch must be pressed. First check. When you stomp on the floor switch does the light on the dash turn on?
Following up from Cmark's question above regarding the switch on the dash, do you have an operation & maintenance manual for the truck.? If not, did you know that you can download one from Cat in pdf form for $46.? It contains loads of useful information.
Cmark, Yes, I have pressed the button on the dash and the button on the floor at the same time. It makes no difference if the dash button is flipped on. Yes the light comes on with the push of the button on the dash or if push the the floor button.
Nige, No sir I do not have a manual for this book and I was not aware of the option of downloading it.
To download an operation & maintenance manual, go to - https://catpublications.com/ When the popup appears, click on "Continue as Guest" Type SEBU7347 in the box and click Search. The illustration below should appear. Should you choose a CD or paper version there will be S&H charges on top of the price. All three versions contain exactly the same information. If you select and pay for a download it will be available by clicking the "Manage Orders" button in the Login drop-down menu (don't ask me why) visible on the RH side of the upper menu bar close to the shopping cart. You don't need to create an account to do this, it's all possible as a Guest.
There are two solenoid valves on the side of the transfer box. You should probably start there by checking for power when the diff lock switches are turned on. Can somebody give Chandler a wiring diagram? I'm not near SIS right now. Obvious question but is the oil level in the transfer box tank OK?
Here's a thought. I wonder if it has any Diagnostic Codes on it.? This is a truck that's old enough to have the Service and Clear switches hard-wired into the cab wiring. It should be possible to get any Codes up on the Monitor screen. Chandler, can you confirm that your truck has the two switches shown in the illustration below are actually present on the panel directly below the fuse box..? If they are there then we can probably go further and see whether or not they work and if the truck has any Diagnostic Codes present. Sent via PM.
Cmark, I will check to see if power is going to the solenoids tomorrow. Also there is plenty of fluid in the transfer tank. Nige,Thank you for that world of information. The truck has codes being thrown currently. It’s been that way since I got it. I don’t remember the codes but I’ll be sure to get them. Also the truck does have those two switches that you are referring to.
Chandler, read this thread and come back if you have any questions. HeavyEquipmentForums Diagnostic Codes are accessed via Mode 3.
Hello, I have a similar issue with my Cat 730 AGF truck… the main pin #10 and A brace fell out on a job. The top bolt #17 worked itself loose appearently. The A group is still in tact. I tried to swing the A brace up with the main pin 10 through the B assembly and there was an alignment issue. My question is, do I have to press the main pin 10 out and then drive the top half of section B together and then swing the A brace up and press that? Or can I just try to align the bore and swing it up and press it back together? It seems the longer pin option would be more difficult to set so do the top half then swing in the bottom…? I’m trying to get it back together for a couple days and then into the shop for a better inspection/ repair. However, I’ve already got the job 1/2 way done in the field so….
The way I've always seen work done on that bearing/pin at the back end of the A-frame is to block the front axle on both sides and unbolt the A-frame from it. At that point things become much easier to manage. Attempting pivot it upwards around the front axle and swing it up from the bottom I don't think you will have enough room to align the pin with the bore. Also I'd bet money the spherical bearing is toast and will need replacement anyway.
Alright sir, thank you!
I guess the question ought to be what caused it to come down in the first place. They don’t fall down all on their own in my experience.
I think the main bolt 17 worked itself loose. I was wondering if the section A section above section B has too much tension on it? Possibly unbolting the bolt 17 from too much tension
Even if that is the case, maybe the bolt working loose is a symptom of something amiss somewhere else.? A complete disassembly and a good look might be called for.
Complete disassembly of what exactly
The complete pin/spherical bearing assembly. There may even be an issue with the tapered sleeve. Without disassembling it’s impossible to see what might be wrong. I’ve seen a number of spherical bearings get wear in them, usually when the grease line breaks and nobody spots it, but I can’t ever recall seeing the bolts (#18 on my parts illustration) come loose/fall out.
# 18 bolts were fine. It the one #17 that goes in the top of pin # 10 that worked loose and let the A brace fall out
I'm afraid there's no quick fix for what you have going on there. Notice there's two tapered sections to the pin. These fit in corresponding tapered holes in the chassis. By now these tapered holes are out of shape and won't properly hold the pin without repair. You can try and get the pin back into the hitch in order to move the machine but with the weight of the machine on the front axle it will be a (potentially dangerous) fight. As far as a temporary fix goes, if you do manage to wrangle the pin back in, sending it to work will be making things worse in the long run. Personally I would: . Remove the front drive shaft. . Lift the A frame up as best I could and chain it to the chassis so it doesn't drag on the ground. . Carefully recover the machine to some good hard standing where the two halves can be split.
And just to demonstrate that I have something of a track record with these things.
Yes sir, that’s what I was thinking. Getting it back into our shop and working on it. Hopefully it will be a safe transport back with the A chained up
Wow, CMark, looks like you know all about it! Nige also, very much appreciated! I really appreciate the insight
On a slightly off topic,I broke 10 730/735 and 740’s in 2022. I was suprised to find all axels unbolted easily and were removed.The A frames were all pigs however and the gas axe came into its own. I can tell you that all the A frames were the first items to go out the door at strong money,so I assume a common wearing part. After being involved in them,I’d be very tempted to fit those spherical bearings with manual grease nipples rather than the remote pipes. Wether or not,anyone will grease them is another matter,but I’m sure as heck the fitter would if he’s had experience in removing them before