My husband and I repaired our bobcat 753 skidsteer yesterday and were thrilled when we finally had no creeping in either wheel. While we did this adjustment we had the cat up on lifts and the engine running with the cab up. Everything was running fine. I started to tighten up all the bolts and nuts that we had to loosen along the way and hubby says that this should be done with the engine off. So we turned it off and I tightened up the bolt under the torsion bushing /pintle arm and the nut on top of each, then I tightened the bolt and nuts ( in that order ) at the linkage bar. One thing I notice is that loosing the BOLTS under the bushing/pintle arm was extremely easy ( seemed way too easy) but I tightened them up quite tight as the manual says to tourque to 25-28 ft lbs. Anyway, thinking that now my machine would work correctly, I climb in to start it up. It starts up but within a few seconds it makes a grinding type noise- the left steering lever actually pulls back about 3-4 inches and the motor stops. I have noticed this same type of stopping if the safety bar is not down, so I'm thinking it has something to do with a safety feature. However, the seat sensor is/has been kaput and I had the bar down. In order to run it for repair I put the arm down and standing in front of the arm turned the key, pushed the seat override button and started the machine. I was then able to lift the cab and keep it running. (to turn it off I got on a ladder and reached my hand around to the key to turn it off) . Also there is no "play" in the right hand lever, but the left hand lever has that 4 inches of play to it- normal? Does anyone have any idea what could be causing the machine to keep stopping? I'm sure you've guessed but the machine is "new" to us. Thanks for the help
Welcome to HEF aznh. That "play" in right hand lever is your problem, when you start the engine the right side drive pump is not in neutral position because of that play. As soon as engine is started, right wheels turn a bit and are stopped by parking brake in chain case. The grinding noise is the drive pump trying to turn the wheels but can't because of the brake, you're hearing pressure building. Here's a thread that covers working on the drive centering devices on Bobcats, it might help you getting your machine working proper.
got it going again- but Willie59- thank you. Before I get to my problem, I have to say that going back over old post I see you answer clearly with pictures and explanations again and again. Thank you for being so giving of your knowledge. Now, to my bobcat. You were probably right, but I didn't see your answer before going out to attack the problem again. We found that there was no nut on the bolt that connect the bar from the safety bar mechanism to a solid bar going horizontally across. So we put a nut on there, then tried to start it with my holding that left ( if I said right before I'm sorry it is the left-as you sit in the machine) bar in the place that I felt would be neutral- It started up with no problem. The parking brake wasn't on, so I don't know if that would have been it anyway. So now it's running but I'm still very discouraged. I grew up with farm tractors and my husband and I have owned for years a very old IH backhoe loader. However, we no longer have the backhoe and my son suggested that a Bobcat would suffice for the needs we now have. In other words I'm not totally clueless about tractors. First, that left side does still creep, but I was able to compensate for that. The problem is it's extremely jerky and hard to control. In addition the slightess incline and I feel like I'm going to tip over backwards. I know that going up hills I should go backwards, but the place I was just driving was maybe a 6% incline. Our property is totally NOT FLAT. On my backhoe I got into many somewhat precarious situations, but I could always feel exactly how far the machine could go. I did feel a LOT more control driving the Cat this time versus before we worked on it, but it still seems that something is very wrong. My husband is disabled, so I'm the one who uses the machine. I'm going to read your article on drive centering now. Thanks for the help.
Sounds like you have a loose pintle arm connection to drive pump control shaft. It will wander all over the place if one of those pintle arms gets loose.
Willie59, I'm sure you are right and I have to apologize for sounding like a wimp before. I decided to not let a tractor get the best of me so easily and just spent 4 hours spreading, I don't know how many tons, of hardpack on my driveway. I got the hang of using the machine, and have to admit it that the small size does help in certain places. This is what I needed. I feel I have much better control of the machine. I still am leary of all our hills, and it needs on that loose pintle arm dealt with. That was the one thing we noticed this morning, but couldn't figure out how to fix it. I'm going to pay the price for Bobcat to come out here and do some work on it. The ideal thing would be to have someone local who was familiar with bobcats that we could hire. My brothers are all mechanics, but they live 3 hours away. To all you mechanics out there- there is a definite niche for mechanics who work on tractors and do "housecalls". I've tried to find this magical person to no avail. (NH- Antrim area). Thank you for you help.
read through willie thread, all good info there. make sure you adjust the left side neutral before you adjust the right side. the left side has a fixed hole and a slot for adjustment the right side has 2 slots, if you "overcompensate" on the right side, the left side will start creeping. reading through your post, dont overtighten the pivot bolt on the lever/linkage, the steering will bind, and give you fits trying to get a dead neutral. if the aluminum levers on the pintle shafts are loose after you tighten down the pinch bolts, they need to be replaced, it's a common "wear item" :drinkup