Help with a Bobcat 430...

[Diamondback]

I know a lot of folks here use a different term for Bobcat minis but that's what I've got and frankly wish I was aware of this forum prior to my purchase. That being said, here's my problem(s)...

While doing some road repair yesterday I attempted to back up and one track just simply didn't want to move. The other track ran fine. I went forward then attempted to go back a several times, no luck. Got off the machine and looked for problems (something behind the track, in the track, caught in the sprocket), nothing. Fearing the worst, I made one final attempt. Went forward a little further than before and it worked.

I made a b-line to the house and as I was traveling up my drive (pretty steep) I noticed the engine speed began to drop rpms from 2400 to well under 1900 on it's own with the throttle almost wide open only to regain rpm, then shortly after begin to drop again. Over a 1500 ft drive this happened about 4 times. As I reached the steepest part of the drive the rpms dropped so low I thought it was going to die. I stopped, lowered the throttle a bit and continued the last little bit and put it to bed.

Don't know if the two problems are even connected. I've always been aware that the "Fast Track" feature only works on flat ground. Usually have to just cut that off when on inclines as it's useless, at least on my machine.

So here are my questions:

Is this the way the Fast Track works on all these units?

Could I be seeing the start of bad things comming soon with the final drives?

Are the two problems connected?

Is it a hydraulic problem or a engine problem?

I'm only an average mechanic at best so any thoughts, suggestions or recomendations would be appreciated

Thanks, Diamondback

 

[strott]

I believe on most machines the 2 speed tracking is no use when turning at all but it should be able to cope with slopes - obviously not when dozing e.t.c.

Is there any chance that there was some hardcore caught in the track which stopped rotating as that usually jams them up until you rotate the track the other way and get enough momentum to pop the hardcore out!!

 

[Diamondback]

strott,

Thanks for the reply. It's definitely possible something was jamming the track up, just couldn't spot it at the time. Seemed to track fine after the last attempt going forward then back. Still dosen't explain the erratic loss in rpm. Changed the fuel filter just a short time ago. Suppose it could have clogged that soon.

 

[nobull1]

You would think just by timing the two problems are related.....but. I would try changing the filter first because it is easy and relatively inexpensive, and hope for the best.

 

[CRAFT]

I would say that there was no relation with the 2 problems ..... we had 2 near new 430's back in '05 both had an issue with the 2 speed track. ...a couple of questions ? when you are on level ground and in hi speed does the machine pull 1 way more than the other ? .... if in what you explained just swing the house around and pick up that track a little in the air and try to spin it back an forth ... do the same on both sides .... are the tracks tight or loose ? ...... I was informed from a bobcat tech that they had an up date in the swash plates that made the fastrack work ..... as far as your powering out goes it sounds alot like a fuel problem ..... if you are using Bobcat filters they have a drain on the bottom , try to drain abit into a jar and see if it is contaminated, rust, dirt, water can be seen if its there ...... but in a slim chance that it is related the pumps could be over stroking cause of the fastrack issues ...... last but not least did these problems just happen all at once or did it progress slowly ?

 

[Diamondback]

Craft,

Yes, on level ground the machine does pull slightly to one side when tracking at high setting, but not a great deal....The tracks appear to be about right as far as tight/loose, but I'll pick up both sides to verify...sorry, not familiar with the term "swash plates", can you enlighten me? I believe this is an 02 model...do you know when the update on the swash plates was issued?

I do use the Bobcat filters and will re-check it...The fast track situation has been like that since I got the machine, but since I use it around my property primarily it's not a huge issue. Just something that bugged me. The rpm drop concerned me much more. I've put about 150 hrs on it and this is the first time I've noticed such a dramatic change in engine speed...does fine while digging...only while traveling (was not in the rabbit mode at the time).

 

[CRAFT]

Just got off the phone with a former dealer tech, (friend) who had to deal with those issues of the 430's we had ..... he told me that at the time they had all those problems Bobcat had a motor update which is where those swash plates are located ....they are like a variable valve that adjusts the flow to the motor (only piston motors use that kind of valving)... he had also said that the tolerance for sideways pull was like 3' drift in 100', (the ones we had pulled like 3' in 25') that was the acceptable pull before they figured it was a major issue ..... he said because those machines were so new it was just re/re on warranty, and the problems were gone ...check with your dealers around your area ....if they are honest with you they should be able to give you good advice how to deal with your issues ......maybe talk to a hydraulic repair place they may say that its cheaper for them to repair ..... good luck

 

[CRAFT]

Ohh ....PS. not to miss lead you, the pull problem also indicates that there is a power problem at the motor .... we were almost not able to load one on to the trailer, the oil flow was bypassing so bad ....... not to slam the Bobcat ex's but remember they don't build the motors, usually they're out sourced to Eaton, Voag, Saurer Danfoss, ect .....thats why I suggested the hydraulics repair places .....Bobcat dealers would do the same thing if its not warranty and cheaper to repair and not re/re .....cheers

 

[strott]

You weren't by any chance lowish on fuel when climbing the steep driveway where the engine revs dropped??

If the fuel when to the opposite side of the tank to where the fuel hose is then obviously the engine may have not had enough fuel to maintain the rpm's amd when you stopped/slowed down the fuel swashed about in the tank towards the fuel hose and fed the engine some more fuel so the rpm's increased again.

 

[Diamondback]

According to the fuel gauge, between 1/4 and 1/2 tank. Man, sure wish that was the case. Maybe the pick up tube is a little high in the tank? Kind of a pain to take the floor out to check, but that would be a simple fix. Or just keep at least 1/2 tank or more when traveling on steeps.

 

[Excavator759]

i have a 2007 bobcat 430. after my expierence with bobcat since 2006 i will never own another one. my first one was new in 2006 and was a "Fast TRACK" it was the biggest piece of junk machine i have ever seen. with less than 400 hours the back window fell off, the throttle cable broke and i went through 3 mufflers. and the dozer blade would creep all the way down in 15min. the dealer gave me false info on the fast track and that was the worst option for an excavator. it would be fine for a landscaper or if you were using it on flat ground. it was impossible to do any other function while traveling or the machine would shut down. i threatened the dealer with legal action and they did what they could to try and make it better (by turning up the fuel pump) but all that did was make it blow smoke and use way to much fuel and **** me off. bobcat did step up and exchanged it for a conventional track machine and even threw in a hudraulic coupler for dirt cheap. that shut me up for a while. my new machine is a lot better but even it had a ton of problems. If you have a bobcat 430 you better stock up on inline and screw on fuel filters. no other machine i have goes through them as much as this clunker. sometimes once a week. the dealer even replaced my fuel tank and wireing harness. all my fuel is filtered into the tanks on my trucks and also filterd into the machine. sometimes it will bog the machine just a little bit as posted and then be fine for several hours even days.

 

[bobcatmechanic]

they did have a problem in the drive motors on some exs when they came out in the early years of the fast tracks. i would look at that also you can get the hole machine off the ground by pushing the blade down and lifting the back off the ground then put the arm in front and push down and out with the stick at the same time and get the machine off the ground and you can check your track speeds and see if one is slower or faster in high and low

 

[KSSS]

Not that it is any consolation, but BC wasted no time in replacing the 430 with a Doosan machine as part of their partial M series excavator release.


I can remember in the 90's when a BC mini ex was a good piece of gear. Man how things change.

 

[BCTech]

Wow I can not belive the advice Craft has given you as he sounds like he has no real clue here. so hear it is I worked for BC for many years and yes they did have a problem with drive motors in the early years of the 430 But this was delt with fast buy BC. there have been many software updates for these machines and settings that need to be done as there is ajustments for where you want the machine to work the best ( digging or driving ) As for ther tracking issue if you can drive 50 feet and the machine only moves off the center line buy say 10 feet you are lucky and should not have people telling you otherwise! Fast track is meant for level surfaces only!!!!! And as for your power loss and the rpms droping try taking the unit out of high speed and instead of pushing the drive levers full forward let them come back a little and you will notice you still travel the same speed but the rpm issue should be lessend greatly . The trouble that comes from these types of sites is you get two bit hacks trying to give advice about things that we as tech's went to school to learn in great detail! so the best advice I could ever give is get to know your dealer as We went to school and know this equipment inside out. Or you can go this route and have people telling you all kinds of crazy crap.

 

[Diamondback]

BCTech,

Thanks for chiming in. I was getting pretty depressed. And yes, I had the most severe drop in rpm while both drive motors were pushed full forward. And yes again, I did back off slightly and the variation in rpm was significantly less. I can live with it. Just wanted to make sure these events weren't a sign of a major problem on the horizon. Heard some nasty and expensive stories about drive motors going south. Good to hear the Fast Track is meant only for flat surfaces.

Can I assume all BC dealerships have Techs trained like yourself? If so, I should be able to have them check for any updates that may not have been done. This was a used machine with 1900 hrs on it when I bought it and the owner assured me it was in top condition.

 

[Diamondback]

UPDATE: Sorry to bring back a fairly old thread but I thought some may find it interesting...I did. The loss of rpms I experienced started to occur more often over the last year but nothing severe enough to really limit my use of the unit. And the drive motors have done fine with no more problems.

Well last week everything changed. After warming the unit up and starting a small project the rpms dropped suddenly while digging a 50 foot trench. Barely got the job done, slowly walked it to a resting point out of the way and it died. Cranked it back up, sputtered a little, died again. It was getting late so I let it sit til the next day...same performance...poor. At this point I'm not even sure I can load it on a trailer to get to the dealership.

Thinking it may just be a lack of fuel problem I checked the pickup in the tank...fine, changed both inline and regular fuel filters, checked the fuel line...fine. Started the engine up...still not cooperating. While I was standing there scratching my head trying to figure out what else could be causing the loss of rpms I noticed a line coming off the back the injectors that appeared to have some hairline cracks in it. Mechanic buddy of mine said it was a return line that carried unburned fuel back to the tank.

The line in question is close to the exhaust so the heat probably caused the dry rot (2200 hrs). Had nothing to loose so I cut three or so inches off the end of the line that was cracked and re-attached. Bingo! Problem vanished and 4 hrs of fairly heavy work with no hint of rpm loss so far. Could not have been more relieved. Would never have guessed a return line could create such a problem. Don't really care as long as the problem stays solved.

Oh, and thank you to those that responded originally to this request for help. Perhaps my fix will help others that encounter similar problems.

 

[landtekk]

I'm glad you found the problem, I have a 435 and I like the fast track. Low range is still faster than compariable machines in high range. High range is weak but finessing the controls (backing off full stick ) does make a difference. In low range you have to actually back off the sticks so that you don't spin the tracks and I can run on all kinds of slopes without a loss of power.I've had this machine five years and I'm always pushing hard with it and so far no problems that would make me want to sell it. Filters have never been a issue, but jelling of the fuel has happened if I don't use an additive.
I have yet to see a e50 here in Anchorage and I really want to try one out to see if the all the hype is true. I've watched videos of e50 and really don't see anything that the e50 can do that I can't do with the 435. The thumb modes on the controls change for some reason and I will hear a relief valve squeal and a loss of power but changing the mode cures the problem. pain in the butt though when you are in a hurry. Good Luck

 

[strott]

Thanks for keeping us updated.

Heres hoping for many more trouble free hours of excavating.

 

[zokabear]

Same problem?

Wondering what year is your excavator? I have a 2004 that seems to have the same problem.

UPDATE: Sorry to bring back a fairly old thread but I thought some may find it interesting...I did. The loss of rpms I experienced started to occur more often over the last year but nothing severe enough to really limit my use of the unit. And the drive motors have done fine with no more problems.

Well last week everything changed. After warming the unit up and starting a small project the rpms dropped suddenly while digging a 50 foot trench. Barely got the job done, slowly walked it to a resting point out of the way and it died. Cranked it back up, sputtered a little, died again. It was getting late so I let it sit til the next day...same performance...poor. At this point I'm not even sure I can load it on a trailer to get to the dealership.

Thinking it may just be a lack of fuel problem I checked the pickup in the tank...fine, changed both inline and regular fuel filters, checked the fuel line...fine. Started the engine up...still not cooperating. While I was standing there scratching my head trying to figure out what else could be causing the loss of rpms I noticed a line coming off the back the injectors that appeared to have some hairline cracks in it. Mechanic buddy of mine said it was a return line that carried unburned fuel back to the tank.

The line in question is close to the exhaust so the heat probably caused the dry rot (2200 hrs). Had nothing to loose so I cut three or so inches off the end of the line that was cracked and re-attached. Bingo! Problem vanished and 4 hrs of fairly heavy work with no hint of rpm loss so far. Could not have been more relieved. Would never have guessed a return line could create such a problem. Don't really care as long as the problem stays solved.

Oh, and thank you to those that responded originally to this request for help. Perhaps my fix will help others that encounter similar problems.

 

[Diamondback]

Zokabear,

It's a 2002. Put another 100 or so hours on it since the fix. No more problems with rpm loss but now need deal with a persistent leak that appears to a hydraulic line. It's under the floor plate and seems to be getting worse. Guess the fun never ends. Good luck.