Repairing creeping Bobcat

[willie59]

Awesome! :drinkup

 

[jiujitsu]

updated pintle arms 175

First let me say great write up willie59. I hope you see this question soon however. Bobcat decided to do away with the aluminum pintles, and has updated them to the cheap heavy cumbersome chinese variation. This has been a pita! !!! Not only did I have to buy thr arms, but to add insult to injury bobcat failed to inform me (at least my local dealer did, BINGHAM) that this requires purchasing the entire assembly!!! WTFF!?!? Through trial and error i finally got both arms on and secured to the pump (thanks to willie59) i realized that with all the added bulk of the new style pintle arm the old centering plate will not fit over the new arms. Am i overlooking something here?? Not only has this couple hour job turned into my machine being down all week, mostly because of necessary parts being ordered 1 or 2 at a time, but its been expensive as well. Why in the world wouldnt bobcat include every nut and bolt needed for a swap? At least inform the customer what is required to make it work.
My question for you willie59, is, do i need to replace the centering plate or is there a trick to get it over the larger pintle arm on the right side? It seems like the tabs that hold the rubber grommets need to be about 1/2" longer to compensate for the added thickness of the steel pintle arm. I installed everything according to your photos and the illustration in the parts manual. No matter which way i turn twist rotate or force it, there is no room between the centering block on the plate and the right pintle arm. I may be able to install it if i bolt the centering bar to the plate after i slide it over the pegs, but i was too exhausted tonight to keep at it. I will start with a fresh mind in the morning, hopefully either you or bobcat service dept. Will have the answers i am looking for. If i end up having to fork out more dough to make this work I'm going to make sure the poor sunuvabitch on the phone at bobcat knows the precise level of frustration i am feeling about their bright idea on changing the design. Please if anyone else has input on this i need the assistance ASAP Sw33per@yahoo.com

 

[jiujitsu]

 

[jiujitsu]

here are the pics . obviously something here doesnt fit. bobcat is no help and they tell me this is the only pintle arm available for my serial number..HELP

 

[willie59]

I can't tell for certain because of the angle of the pics, but it looks like you have the wrong centering plate, that looks like the centering plate for the aluminum one piece pintle arms. The two piece steel pintle arms require a centering plate that has oblong shaped holes in order to do the creep adjustment, see the holes in the plate in pic below.







Now, what I don't know, I don't know if the brackets that the guide pins are mounted in is different between the two pintle arm versions, therefore I can't say for certain this will fix your problem. But best I can see your pics your centering plate has two round holes just above the bolts that mount the drive lever links, no oblong holes. If that's the case, you for sure have the wrong centering plate.

 

[jiujitsu]

Yep. I friggin knew it! I had enough and got that lazy parts guys boss on the phone and what do ya know, they DO sell the aluminum arms. He was being lazy and was just going off of my serial number, and even though intold him i had the aluminum ones, he insisted i had the steel version. Turns out the serial number on this machine says it came with steel, but for som3 reason i got lucky and have the one piece version. I followed the rest of your tutorial and its like brand new. The guys will be pleased the next time they are in a back yard next to an 8' brick wall haha, that thing was impossible to control and a serious safety hazard! Thanks willie youre the man.

 

[willie59]

I don't know if the parts guy was being lazy or what, no way I can say, but if he knows Bobcat well at all, the S/N doesn't always confirm which pintle arms are fitted to the machine, Bobcat has been mixing those parts up for years as long as I've been working on them. Maybe the M Series has got it sorted out and only use the 2 piece steel pintle arms, don't know, haven't worked on them enough yet to know, but with the G Series cab, it's a toss up, especially the earlier year models.

 

[crewchief888]

starting some where with the K series machine ( basically a G series with a hyd driven fan) bobcat changed from the aluminum levers to a 2 pc steel design. the early design is no longer available, and has been replaced with an updated design that doesnt fall apart :cussing

steering adjustments are much faster/easier with the 2pc design.

the new 2 pc levers arent a replacement for the older aluminum. whatever your pump has on them, thats what they have to be replaced with.

several years ago, bobcat changed the press in bushing for the "redesigned" aluminum lever. with the new (larger OD) bushing you need a longer bolt and an additional washer.

i'm really surprised an authorized bobcat dealer's parts dept could screw this up..

:duh


:drinkup

 

[Ads]

Yep. I friggin knew it! I had enough and got that lazy parts guys boss on the phone and what do ya know, they DO sell the aluminum arms. He was being lazy and was just going off of my serial number, and even though intold him i had the aluminum ones, he insisted i had the steel version. Turns out the serial number on this machine says it came with steel, but for som3 reason i got lucky and have the one piece version. I followed the rest of your tutorial and its like brand new. The guys will be pleased the next time they are in a back yard next to an 8' brick wall haha, that thing was impossible to control and a serious safety hazard! Thanks willie youre the man.

How much did the arms cost. My 751 has the alloy arms but I'm in Australia so I'm curious how much of a price difference there is. Cheers.

Adam.

 

[Ads]

Now a little info about the older machines with aluminum pintle arms. Got in the cab of the 753 customer had dropped off and it was all over the place. I knew immediately that the clamping bolt for the right drive pintle arm had come loose. Well, here's the belly of the beast. Pretty much the same thing as on the T190, cage the centering spring with cable ties, remove centering spring, then lift neutral centering plate off. On this model, more difficult to get to the centering spring, had hoses and stuff in the way. Grrrrrr.

View attachment 67854

Centering plate removed, the pintle arm on the left is the one the clamping bolt that holds arm tight on pump shaft came loose allowing pintle arm to wallow all over and couldn't control pump shaft movement. These machines drive nutty when they come loose. Notice the difference in the spools on the aluminum arm models as opposed to the spools that wear on the T190 mentioned earlier. These spools actually look like a chromed steel.

View attachment 67855

Minimal wear on spools as well as centering bars.

View attachment 67856

View attachment 67857

Two new pintle arms. One from being worn by loose clamping bolt, other had excessive wear where rubber torsion bushing goes. Install new torsion bushings, installed old but still good spools on new arms, rotated them around to fresh steel, and rotated centering bars on centering plate.

View attachment 67858

I should offer an installation note whenever perfoming repairs to Bobcat drive linkages. Whenever you remove the bolt that attaches drive link to pintle arm via the rubber torsion bushing, when you go to re-install the torsion bushing bolt you must have the pintle arm near the neutral position. Once the bolt is tight, moving the machine drive lever fwd and rev actually twists the rubber of the torsion bushing. Point is, if you had the machine drive lever and pintle arm all the way forward and installed the torsion bushing bolt and locked it down, then when you pulled back the drive lever, it would simply try to go back foward like a spring was pulling it. That's from twisting the rubber of torsion bushing. Always have pintle arms in line with each other when installing torsion bushing bolts.

continued...

I've just redone my 751 but I also had to change both bell cranks and the bushings for them. I found the whole job fairly straight forward and I was surprised by the price of the pintle arms and bell cranks, 46 AUD each for the arms and 130 AUD each for the bell cranks. Changing the bell cranks wasn't too difficult but took a bit if fiddling to get one end out to slide them off the shaft. Once both were done it was like driving a new Bobcat. One thing I will tell you is that the original bell cranks are obsolete and the new ones take a 26.5mm torsion bushing, not the 22.5. There's a note in the parts book so check it before you take the parts home.

 

[Ads]

I'd also like to add that when I was doing up the bolts in the torsion bushes I nipped them up then backed off the bolt just enough to allow the bolt to turn in the bush and locked it up with the lock nut. This way the bush isn't twisting every time you move the levers. All my torsion bushes were torn apart internally.

Adam.

 

[willie59]

Nice work Ads. :drinkup

 

[Al Miles]

Thank you Willie59, I have my 743 up on blocks trying to find where the hydraulic oil is leaking from the valve bank. Thought I would check this forum to see if there was a more common place on the valve bank that often leaks, when I found this most interesting thread.
My machine also creeps forward but only when it first starts, after it runs for 10-20 minutes it idles in neutral. I will inspect the parts for wear and adjust as you described. Perhaps one of my snags will be repaired.

 

[mrfixitpaul]

Most common leak on valve bank is the seals on the spools. also could be one or more of the jam nuts on the hose fittings loosened up and leaking where it goes into valve.

 

[Al Miles]

Thank you.

 

[WIG6000]

Just want to thank Willie59 and all others who've contributed to this long and old thread. Just got done with the creeper repairs on a 773G. Unit had the aluminum pintle arms so they got new bushing, rotated the centering spools & flipped the centering bars. First one I've ever done and with all the input on this site it was a piece of cake. Todd at Bobcat of Madison (Wis.) was awesome and lined up all the correct parts and this thing drives like a dream! Just a question of curiosity - could a unit with creep cause damage to the lock pin in the park brake system due to loading against it all the time? This was a project for my wife's dad and he'd had to replace the lock pin assy in the park brake system and I was just wondering if the creeping problem may have contributed. Thanks again for the excellent info!

 

[crewchief888]

Just want to thank Willie59 and all others who've contributed to this long and old thread. Just got done with the creeper repairs on a 773G. Unit had the aluminum pintle arms so they got new bushing, rotated the centering spools & flipped the centering bars. First one I've ever done and with all the input on this site it was a piece of cake. Todd at Bobcat of Madison (Wis.) was awesome and lined up all the correct parts and this thing drives like a dream! Just a question of curiosity - could a unit with creep cause damage to the lock pin in the park brake system due to loading against it all the time? This was a project for my wife's dad and he'd had to replace the lock pin assy in the park brake system and I was just wondering if the creeping problem may have contributed. Thanks again for the excellent info!

machine that are creeping really bad, or for a long time, have a tendency to bend the long bolt, and mangle the spring on the brake system. the constant "push" and slamming the machine back and forth to release the brake loosens the 4 guide bolts, the guides fall into the chaincase along with the plunger, springs, and wedge. let it go long enough, then one of the pieces gets jammed under a sprocket and if you're lucky only jams up that side. worst case is the debris gets jammed into the bottom of the chaincase, and lets all the oil out.

 

[willie59]

machine that are creeping really bad, or for a long time, have a tendency to bend the long bolt, and mangle the spring on the brake system. the constant "push" and slamming the machine back and forth to release the brake loosens the 4 guide bolts, the guides fall into the chaincase along with the plunger, springs, and wedge. let it go long enough, then one of the pieces gets jammed under a sprocket and if you're lucky only jams up that side. worst case is the debris gets jammed into the bottom of the chaincase, and lets all the oil out.

Agreed, it's worth pulling the parking brake dog out and give it a good inspection. Another thing that can cause parking brake dog damage is a parking brake solenoid that goes up in smoke while driving. Had that happen to me once in a 773G going full tilt. Man...talk about putting the brakes on!

Good to hear you got your machine fixed up WIG6000

 

[WRB1717]

Willie59: New to this forum. Usually go to skidsteer forum but could not find what I needed. You are a lifesaver and a big bucks saver! Thank you ever so much for your detailed, photographic post. I have a 2000 763 Bobcat that was doing a lot of jerking in forward and reverse at full rpms and low speed. Replaced four torsion bushings and one pintle arm. Getting neutral setting had me stymied until I saw your post. Hope you are still around to see that you are still appreciated.!!!! WRB1717

 

[WRB1717]

Willie59: New to the forum. Usually go to skidsteer forum but could not find what I needed. You are a lifesaver and a big buck saver. I have a 2000 Bobcat 763. It was jerking in forward and reverse at full rpms and low speed. At full speed in forward and reverse it was okay. I replaced four torsion bushings and one pintle lever (aluminum). Getting the neutral setting had me stymied till saw your post. Your detailed, photographic posting was spot on. Thank you ever so much. I am a fan. Since I saw your posts were from 7+ years ago, I can only hope you are still around to see that you are still appreciated. WRB1717