B7500 Engine RPMs

Anonymous Poster · Jun 18, 2003

Hi All,

Well I've been lurking for quite some time now and I must say this has to be the most informative, curteous, sharing, helpful and kind group of people I've come across online. It seems we all have a common goal of cooperative learning. I'd like to thank you all for all the information I've learned from you....

Enough blubbering, sniff, sniff /forums/images/graemlins/crazy.gif and on with the question. When I bought my B7500, the dealer told me not to ride the engine too hard for a while until all the new parts "had time to get to know each other." Well, I'm not sure what running it hard is, I guess. I've been trying to keep the RPMs to around 2000ish. That sound OK?

I just had my 50-hr service done on it, so can I unleash the beast now? I've had the RPMs up to 2500 briefly and it sounds so "revved". I will be frontloading a lot of rock (blasted ledge), so really the engine load is when I bite into a big bucket's worth of dirt/rock....

Thanks again all!

TresCrows · Jun 18, 2003

Well, you will get your first answer from the dreaded 3Crows /forums/images/graemlins/cool.gif (or should it be /forums/images/graemlins/tongue.gif). I am sure you did fine on breakin from what it sounds. Ok---why do you think you need full throttle for loader work when the Loader Manual says 1800 or so RPM?? /forums/images/graemlins/confused.gif Much beyond that and the loader becomes somewhat jerky and the limit valves are not going to allow the loader to lift anymore at 2500 than at 1800/2000. The only times I use PTO RPM is when Brushhogging. I generally mow (MMM) at about 2200. Most tooling around and everything including FEL work at about 1800 and boxblading 1800 to 2200. Boxblading occasionally needs max power /forums/images/graemlins/grin.gif. My unit is a 2410, high dollar brother to the 7500, so I figure there is not much difference. When doing FEL work if the bucket should stall, rev the engine, once free set the throttle back down. It want get stuck at 2000 RPM anymore I doubt than at wide open. This will save your tractor, your fuel and your ears /forums/images/graemlins/grin.gif. J

robertm · Jun 18, 2003

Gunnahafta,
Have a B7500 and am just going to do the 50 hr service this weekend. My dealer told me to run it "out of the box" like it was going to run all the time. I agree that loader work should be at the 1800 RPM range, but mowing is tached up allthe way, about 2700, I think it reads. I have asked alot of people I know who own Botas and other diesel tractors, and they do not disagree. Right or wrong, mine purrs like a kitten always. I've run many diesle engines on the road, and fresh off the dealers lot, 70mph till they were given up to the next one. At 70,000 miles and up, still no problems with poor seating of rings, parts, oil consumption, etc... Just my $0.02.

Bird · Jun 18, 2003

Gunnahafta, in my opinion, let'er rip, and don't worry about it. It's got a governor so you can't over rev it. For mowing and tilling (anything using the PTO), I ran'em at the 540 PTO speed. And for most FEL, box blade, etc. work, usually 1800 to 2200, primarily because it was quieter and that was all the power I needed. And naturally if you've been running it at 2000 rpm and now you want to run 2600-2700, it's going to sound to you as if it's really revved up. It was made to run all day at whatever that 540 PTO speed is (2640 on the B2710, wasn't it?).

Anonymous Poster · Jun 18, 2003

( why do you think you need full throttle for loader work when the Loader Manual says 1800 or so RPM?? )

So far, I haven't really had a need for full throttle, just wondering whether it will hurt anything (other than my ears) if I open her up a bit at times. Only time it has bogged down much is when I drive into a full bucket filling or try to take on too big a stump....

So what you are saying is that I won't get any more power at 2500 than at 2000?

Thanks for your responses!!

TresCrows · Jun 19, 2003

"So what you are saying is that I won't get any more power at 2500 than at 2000?"

Yes and no. You will get more tractive power but the loader is limited by a preset relief valve and once max pressure is reached it will bypass whether at 1800 or 2700--max lift pressure is max lift pressure. The pump will put out more flow which will cause the loader to react faster and somewhat jerky in my opinion but it will not lift more weight or be more "powerful" --- that is controlled by the preset relief pressure.

Scotty, I need more power, sir, I canna not get no more power, the cannuder valve is in hyper mode /forums/images/graemlins/shocked.gif.

Dealers say what they say, I go by the manual till proven otherwise.
J

snowman · Jun 19, 2003

Same answer as everyone else - when mowing, I run my B7500 at 2500 or slightly more. Any less, and I get a lousy cut. I run it the same for the tiller.

For loader work, I rev it up and down as needed. Once I get a bucket full of dirt, I'll run it slower until I dump it.

It's been said in many places here that diesels are made to be worked hard; it seems to be true because when I've had it running for hours the engine seems to actually run a tad bit smoother.

Bird · Jun 19, 2003

( in my opinion but it will not lift more weight or be more "powerful" )

Trescrows, I don't know how much pressure the hydraulic pumps put out at what rpm, but I do know that, on my B2710 at least, the higher rpm definitely put more power to the loader. I found that in several situations, but for one example: I lifted a 454 Chev. engine, with transmission attached, over the grill and into the engine compartment of a Suburban. I had no problem lifting it off a trailer and moving into position with the tractor running about 2000 rpm, but I couldn't lift it quite high enough to get over the grill of the Suburban, so I went to full throttle and raised it the rest of the way.

TresCrows · Jun 19, 2003

I have not noticed that so much with mine but I imagine tractors are different. In any case once mine gets to about 2,000 RPM or so it does what it does. Turning the engine faster makes it more responsive, maybe a little more "powerful" but mostly just lot's of engine noise. Like I said, if it gets stuck, rev the engine a little, rock the tractor etc to help the FEL. I don't think there is any need to drive aound with the engine full blast to move a bag of mulch or even a loader full of dirt. I don't think my IO360 is as heavy as a Cheby but I used about 1600 RPM so I could gently operate the loader without thinking about it so I could keep my eyes on the 25,000 dollar prize. Shoot, maybe my 2410 is more "powerful" than a 2710 at reduced RPM /forums/images/graemlins/grin.gif. Guys and their "powerfullness" /forums/images/graemlins/wink.gif. I think in my next life I will ask the crows if I might be a woman or at least a dog (but not at the same time /forums/images/graemlins/shocked.gif), women and dogs have so much more sense than men /forums/images/graemlins/tongue.gif.
Often finess will get better results that brute "powerfullness" . J

fishman · Jun 19, 2003

Bird,

I have noticed the same thing when lifting things near the capacity of the loader. More revs seemed to give it that little extra nudge it needs.

When moving dirt, it definitely makes a difference, but that could just be due to the tractor and not the loader as stated before. Regardless, there are situations where max rpm is very useful when using the loader.

I tend to run mine between 2 and 2.2k rpm.