Bobcat lowers hydrualic pump output

[Yellowdog]

Anyone notice that Bobcat dropped its high flow hydraulic output back down? Was at 40.5 now at 37 on s300 and 250's. We have had overheating issues down here in S. Central Tejas and Bobcat won't "admit" anything. I have heard from reliable sources that the new pumps overheat the s220 and s300 in 300 minutes when under load (without contacting anything running a planer or brush mower). Anyone heard of that?
Does anyone know of a reliable aftermarket cooling fan that would work on a bobcat and still allow for the cleanout of radiator area periodically during the day?

Thanks!

[Tigerotor77W]

Your first question:

Anyone notice that Bobcat dropped its high flow hydraulic output back down?

Nope, didn't even notice. I'm beginning to think I need to change my user name... :slomo

But I'll do some checking on Monday. If this is true, then it means that Bobcat's cooling system isn't as good as a very-old Worksaver article claimed... a few years ago, they claimed that the dual-path cooling system was the industry's finest. Since they haven't changed that at all, I guess they never planned for it to handle the heat generation of a high-flow system. Man, I really wish Bobcat would get its rear in gear on certain things. And this is from me! I learned skid steers with Bobcat... and now... :(

Okay, happier things: it was a very nice day today!

[Yellowdog]

I have been complaining for years about the cooling system. Here in the Texas Hill Country, we get temp extremes, extreme dust, thick, wet clay particles that clog the radiators, and "fluff" from high grass and the ever present juniper needles. All of this, when pulled through a triple-stacked cooling system, lends to ineffective cooling when running high flow attachment.
I have practically given up my "extreme" mowing that used to be profitable. Since I began running cab and air and taking on more and more tough mowing jobs, I have seen more problems with my cooling system becoming clogged. I think I spend more time blowing out my radiator and vacuuming it than I do working! It is very frustrating and sad that Bobcat will not address this problem or even acknowledge it. Almost lost me as a customer to Caterpillar but I stayed with Bobcat buying a new s300 high flow and an s220 high flow both with cab and air. I operate both machines myself and while the 300 cools better for some reason, both get hot running high flow brush mowers. Like I said, my air compressor gets a real workout as do I climbing in and out of my machine. If I do not have my truck parked close by, I am in trouble on a particular dusty or dirty job when running the brush mowers.

Bobcat says since they didn't design the mowers they are not really approved to run on the Bobcat. Well, as a tool carrier, Bobcat will be losing market share because the trend in this area is brush mowing.. I have contemporaries running ASV 100's with cab and air and they do not have the cooling issues that I have. And it's not just me. My local dealer has had a number of complaints from guys running the same setup.

Maybe the Bobcat engineers will look at this posting and the letters I have sent them and maybe someone will address and come up with a fix.. I may have to do it myself if I want to stay in business!

[Tigerotor77W]

Out of curiosity, does Cat have the same issue? Do other makes (not Bobcat and Cat) have this issue?

I'll see if I can pass along the comments.

[Steve Frazier]

I don't have a temperature guage on my Cat,there's an overheat light that comes on, but I've never seen it. I run a backhoe on mine frequently, this puts the most demand on the hydraulics of all my attachments. It runs on the standard flow.

I run a snowblower in the winter off the high flow side, and again I've never seen the overheat light come on. I'll run this for 3 hours steady at full throttle, if it were going to overheat I think that would do it.

[Yellowdog]

Shoulda bought a CAT? I dunno. I talked to a CAT 268B running a mulching head just like mine. I run an S300 high flow. The CAT runs hot too. It's all machines, from what i have been able to determine EXCEPT the ASV 100, however, the ASV does get warm after about 6 hours and then has a hard time keeping cool..or so I have heard.

The Bobcat s300's cooling system and the CAT's cooling system are quite different. I demoed a CAT 248b and 268b. Didn't have much time on the 268B but could see that the outboud air across the radiators was an advantage. Similar to how the big loaders and graders are cooled. The drawback is that the 268b has open areas on the sides (to pull air in I suppose) that need a fine mesh or screen to prevent stuff from getting pulled through the bottom of the radiator and clogging it like the Bobcat gets clogged. It is a given to get out of the cab and clean your radiator screen. Why not have a better mesh? Maybe that's my problem. A better mesh that will allow air in but not the cedar needles and small pieces of grass?
As long as we are engineering, why not have a freon type cooling system that actually cools the coils like a ac radiator? Anyone understand AC systems?

[Tigerotor77W]

You talked to a 268B, eh! :drinkup Naw, just kidding around... but I'll try to keep some humor going, ..., okay, not. :(

It would take either a lot of coolant or a huge machine to cool the heat produced by an engine. In some senses, it's like trying to cool your house by leaving the fridge door open. Even if you were able to vent the heat generated by the compressor (the "part" that cools the refrigerant) to the outside, eg the environment, you would have to run plumbing or venting all over the place to get it cool. Imagine how long it takes to cool a car interior heated by the sun with AC at optimum settings (either full blast or coldest air, whatever is more effective), and then imagine doing so with twice or three-times the heat -- AND having to do it effectively enough so that you can keep the soda in your McDonald's cup cold. It may not seem like much to try to get heat OUT, but when you've got to keep fluids under a certain termperature (lest they expand and blow their pipes), it gets a little more tricky.

Not saying it can't be done, but hmm... how to say this... it may not be on the minds of small-engines manufacturers at the time. As engines move toward Tier IV/Stage IIIa emissions standards, there may be changes to engine cooling. But in a SSL, :(, you might have a harder time getting people to change that.

Now for the cooling in a Cat vs. Bobcat -- darn, I've forgotten this. Cat and Bobcat use the same style of cooling -- where Bobcat draws in clear air from the top and vents it out the sides, I believe the Cat is opposite. This concept of "dual-path" cooling is in both machines, even though the premise of actually cooling the air is different. The Bobcat uses a belt-driven fan, I think, whereas the Cat uses a hydraulically driven fan. Meh, either way, I'm not helping the situation here... so I'm not sure what you could do.

As far as the S220 overheating -- I haven't heard anything about it being a major, widespread problem. The reduction in pump flow wasn't detailed as a design flaw causing the engine to overheat, as it addressed performance issues elsewhere, but Bobcat may have used it to partially cover their rears if it was an issue. Not sure.

That's enough rambling for me...

[digger242j]

You talked to a 268B, eh!

I talk to machines all the time. Sometimes they need a little encouragement... :yup

[Squizzy246B]

I talked to my machine today when I rolled off the truck in front of the new clients, went up the kerb and blew a tyre with everybody watching...I called it a *#!!*&$@!!!> piece of *!@&^^##*** :cussing

[CascadeScaper]

In my opinion, the Bobcat cooling system leaves ALOT to be desired. Cat's hydraulic driven fan pushes air up and out instead of pulling it in, reducing dramatically the amount of debris that can become clogged in the radiator. We've never seen overheating due to dust/debris in the radiator and we work in 90-95 degree temperatures all summer long.

[Tigerotor77W]

In my opinion, the Bobcat cooling system leaves ALOT to be desired. Cat's hydraulic driven fan pushes air up and out instead of pulling it in, reducing dramatically the amount of debris that can become clogged in the radiator. We've never seen overheating due to dust/debris in the radiator and we work in 90-95 degree temperatures all summer long.

Has the air intake in the sides of the machines given you problems? I would *think* (note that perception/thought doesn't always reflect reality, so I'm not trying to push my own agenda here) that no matter where you take air in, unless it's from inside an enclosed cab, you can clog a filter -- or a radiator. I take it that doesn't happen, then?

And it would seem that Bobcat could put a reversible cooling fan in, but hasn't done so... hmm... suggestion time? :D

And Squizzy, now now, it wasn't the machine's fault... it was the tyres. Although they were probably cursing at the machine, too, though, for being too heavy at the moment they broke.

[Dwan Hall]

Back in the day!

I have 3 Bobcats all 975 machines with 32 gal highflow pumps and after 8 hours at full throttle, none get even close to hot. There was an option for a pulling fan which reversed the flow of air through the radiator back then. I can not tell the differance in running temp with eather fan. it is important to keep everthing clean, all belts tight, and proper antifreze mix for proper cooling. also if a hydrolc pump is warn a bit then it will also creat heat. as will to small of supply and return lines or even a small kink (restriction) in a line.

[Yellowdog]

In my opinion, the Bobcat cooling system leaves ALOT to be desired. Cat's hydraulic driven fan pushes air up and out instead of pulling it in, reducing dramatically the amount of debris that can become clogged in the radiator. We've never seen overheating due to dust/debris in the radiator and we work in 90-95 degree temperatures all summer long.

I worked side by side a CAT yesterday. He was doing the same mowing I do. He got clogged the same as me albeit not as fast and had to go to the compressor for help. His radiator looked totally clogged. I usually blow mine out before a warning comes on..

I don't usually have any problems with dust. I was moving burn piles (ash, dirt, and travelling over dusty ground with 25 mph winds yesterday. I did that for 7.5 hours while my buddy mowed. He got hot, I didn't. The day before I mowed.. I got hot from the radiator clogging. It may be the particle size.. ??

[Yellowdog]

Back in the day!

I have 3 Bobcats all 975 machines with 32 gal highflow pumps and after 8 hours at full throttle, none get even close to hot. There was an option for a pulling fan which reversed the flow of air through the radiator back then. I can not tell the differance in running temp with eather fan. it is important to keep everthing clean, all belts tight, and proper antifreze mix for proper cooling. also if a hydrolc pump is warn a bit then it will also creat heat. as will to small of supply and return lines or even a small kink (restriction) in a line.

What kind of psi are you running? I know the 975 had a lot of room in it "breathing space" right?
Also, the newer, tighter machines with AC and lots of electronics seem to run hot. It's not just me. The other Bobcat guys in Texas that mow complain too. Bobcat told me today that the new machines with 37gpm flow at 3300 psi have a slightly larger oil cooler. Maybe that will help?

[Yellowdog]

In my opinion, the Bobcat cooling system leaves ALOT to be desired. Cat's hydraulic driven fan pushes air up and out instead of pulling it in, reducing dramatically the amount of debris that can become clogged in the radiator. We've never seen overheating due to dust/debris in the radiator and we work in 90-95 degree temperatures all summer long.

Maybe I need to install an ice maker that catches AC runoff and drops ice on the radiators! :)

[CascadeScaper]

That's sounds like a plan! Haha. S250, the side vents have not been a problem either. If you've never seen a Cat skid steer working in a dusty lot, it's kind of amazing to see how much crap it's blowing up in the air that ISN'T going into the radiator core. On a good and dusty day the fan will blow dust 10 feet in the air.

[Yellowdog]

We got rained out for 5 days but finally finished the mowing of 21 AC and reclaiming the land from high, tangled grass and brush. The CAT I was working next to overheated as the radiator was clogged from the grasses. The operator had to blow out the radiator a few times but his warning lights came on another few times.. I had the same problems but I can at least scrape off my radiator grill occasionally. Good exercise climbing in and out of the cab. If I had a charge air system that could blow it out...before it gets sucked in.
Bottom line, the CAT 246 sucked stuff in the sides and the bottom of the radiator did become clogged. Easy to access, though. Bobcat has a real tricky way of lifting the pancake stacks to get to the bottom cooler without damaging the aluminum fins.. poor design, period!

[CascadeScaper]

Hmm, I haven't had to deal with larger debris clogging the radiator that is associated with that kind of mowing, but I know dust doesn't stop us whatsoever.

[Tigerotor77W]

For some reason, I tend to miss threads left and right... sorry, CS, for the late reply. :drinkup

Anyhow, yeah, I ran a 257B today and saw the shadows from the dust going up. Dust and grass may be two different animals, as you mentioned, but hmm, I hope Bobcat fixes the issue. They *better* if they want to stay the leader. Cat's doing a good job, I'm afraid.

[Tigerotor77W]

Checked on the reduced-GPM issue... it's a combination of overheating (larger radiator now) and also with available engine power. The old 40.5GPM machines were lugging the engine more than intended, so they bumped it down a bit to improve that performance.

[Tigerotor77W]

Bobcat will release (who knows when) the K-series skid steer loaders which have a few new features. First, all the beta-sized machines (S220 and up) will have #120 chains (up from #100), which Bobcat claims is a 38% improvement in strength. Second, Bobcat's fan is now hydraulically driven (which is why I put this in this thread), which should address the overheating issues somewhat. It is also a demand fan. Third, lift height on the vertical lift machines appears to have increased to 128.8", but I'm not entirely certain on this. Dump reach and height didn't change enough to make me think that the lift height really did change. I may be missing a few, but man, I like Bobcat again. I'm not sure if this mood swinging is healthy, but I do hope either way that YellowDog, your overheating issues will be solved... *crosses fingers*

I tried to attach two pdfs, but they are too big. You can view them at Bobcat's web site, however:

http://www.bobcat.com/products/aws/pdf/b-1751_AWS_1005.pdf
and
http://www.bobcat.com/products/ctl/pdf/B-1812_FamilyTrack_1005.pdf

[Dwan Hall]

I wish they would produce another machine as big as the 974-975 were. I would buy a new one in a minute. I have 3 that were built in 79 and 80 and the hydrolics are finely starting to get weak on 1 of the machines. I can't find anything to replace them.

[Tigerotor77W]

Is the 963 too small for you? (I know it's smaller than the 974-975.)

You may have to switch over to a compact wheel loader (Cat 908 size)... or a compact telehandler (Cat TH215 or Bobcat 518/723 sizes) in the meantime.

[Dwan Hall]

I like the size and weight of the 975. Also like the JD motor. All my atchments would have to be modified to fit the quick couplers making them non interchangable with my current machines. above all I do not like the Perkins motors. I also have built up a supply of parts. (pins, bearings, wheels, glass, filters, etc)
I have concideded the 963 and used 1 but it just isn't the same.

The 975 was just a good ballance between work, weight, econemy, and maintance. in 25 years I have not had to spend over $500 at any one time on maintance other then tires. And in a 1 on 1 time trial I was able to load my 10/12 yd dump truck with snow faster then I could with a Cat 950 both with 3 yd buckets, using less loading room. I currently have a Cat IT28 and still will use the 975's if posable.

Dwan

[Tigerotor77W]

I've gotta admit, those stories make me a little nostalgic for the old Bobcat... but I hope they'll be doing better with their product and company these next few years.

As far as your operation goes, if you are loading trucks a lot, I'm tending to think that a Cat 908 or Deere 344J will be a great machine for you. Although perhaps slightly smaller than a 975 (at FTSTL), their hydraulics may be faster and their cab more comfortable.

If you want a machine with more reach, compact telehandlers are also rumoured to do well in small spaces.

I know this isn't what you're looking for in your fleet, and in no way do I intend to say "take it or leave it." I just want to throw some other options out there if you need them.

Oh -- and d'oh -- I forgot to suggest the A300. I think it's a grat piece of machinery. It may be a little small for your needs (certainly smaller than the 975), but maybe give it a shot this winter when you have a big snowfall? I know some contractors are absolutely tickled by its features...

[Yellowdog]

Thanks for the info S250. I was waiting to see some specs. My salesman just called me with the news on Friday. I'm ready to upgrade my last year's model s300 and see what good i can do. My environment is about as dusty as can be and any help with the cooling system is good news..

[Mark Oomkes]

I don't think the cooling issue is just the high flow machines problem. We have a T190 standard flow and have run into overheating several times running the Bobcat finish mower. I can't remember exactly what the problems were, but I know we lost the idler pulley bearing, I think the radiator was replaced as well one of the times.

Definitely have not been thrilled with how frequently it has happened.

[Tigerotor77W]

Mark, was the problem successfully addressed? I'm kind of (very) surprised to see Bobcats have overheating problems... but now that it's out, hopefully the K-series SmartFAN will fix 'em.

[Mark Oomkes]

Not sure. The last time was the idler pulley. Have not mowed with it since. Although it did work fine for the rest of the day.

[skidsteer.ca]

Mowing in hot weather is a tough application for any machine. Lots of airborne dust and debris and a high demand on hyd pump and hydro drives makes the maximun amount of heat the engine is cabable of.
If the machine stays cool for a hour or more, its not that the cooling system is undersized, it that the airborne debris is keeping the air from the heat exchanger fins.(coating the fins and insulating them) Either the rads need cleaned or you need to take a break and let the cooling system catch up. Putting a fine screen over top of the air intake would allow some of the corse debris to collect in a place where it is easier to remove.
About all you can do is keep the rads clean( compressed air or oven cleaner and a water pump/ press washer) , try to mow when ambient temps are lower.
However bobcat does use a spring loaded idleler on their fan belts on many models, these are known to sieze over time and the fan belt slips do to improper tensioning. A little oil and tlc here is the fix.
If I worked frequently in these condition I'd have guages on my hyd reservoir and engine coolant to monitor how my efficient my rads are.
We just spent $20,000 on new rads for 4 skidders we have, and have spent 15 years doing everything we can think of to improve the cooling of these machines. But the things that have help the most is cleaning the rads with oven cleaner, and improving fan shrouding to force all the air the fan can move through the rads. While it is easy to say those manuacturers need to.... I doubt they designed it to be less efficient then possible. It would be great if heating problems could be solved permently at the factory, but by the nature of our work, we are going to have to continue to work at the problem on our end to. Coated or dirty heat exchanger cause from dust stirred up from mowing is not entirely a engineering error.
Regards
Ken