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Discussion Starter · #1 · (Edited)
I just took delivery of the Ranger Diesel HST Deluxe model yesterday. The dealer said they had done the prechecks but I found some problems. During the test drive, the dealer didn't have a good place to run them around to do a good run and it was super cold so I accepted his response that the hydrostat wasn't warmed up yet and it was sluggish when I mentioned it to the dealer. My John Deere 3720 does the same thing if I don't let it warm up for around 10-15 minutes. After the tractor is warm, it will run great (And apparently faster than the new HST ranger. Bummer to say the least.) Dealer said there were other ranger HSTs he sold getting up to 35mph but not this one for sure at this point.

With all of that, here are my findings.

1. Dealer didn't inflate the tires. Both rears were less than 5 psi. The fronts were around 4-7. With this being the case, the machine really struggled to move under it's own power even at 3100 rpm. (Max is 3750 based on specs)
2. Idle is a bit high and not running at the rated 1250 the manual states. It is running at 1500-1540, not huge but noisy. What are your warm idle numbers?
3. Basically it seems to be a Polaris Brutus machine from research and it does appear that I may suffering from the same control arm/swash plate issue others have mentioned here on the brutus forums.

I got out this morning and ran a test run after properly inflating the tires to 10psi front/20psi rear (Based on the book). Very big difference in getting the machine to move of course. It took off better at around 2700rpm and then I rode through a 40 acre pasture to a 1/3rd mile gravel back road that has a slight 2 degree incline upward and at the end, a right turn to a gravel road that is also 1/3rd mile long and flat out to the main road.

On the pasture, I could maintain 15-18 mph with the variation of terrain in high gear. When I say variation, I mean 5-10 foot elevation changes over 2-300 yards. That was with no Air, heater running low and turf mode on. When I got the rougher back road in the back I was able to get it to about 18-21 on high going up the hill. Made the right turn and tried to push the pedal through the floor and got it to a stable 24mph but never could get it any higher. IT took about 1/6 mile to get to that speed on the flat. On the way back, even going down the hill, I still couldn't get more than 24mph so that is what she has until breakin is complete.

When I picked it up, it had 12 miles on it, but had ran for 44 hours on the hour meter which seems a bit strange.

Any way, this is my experience with the Diesel HST so far with the few minutes I have driven it.

Final thoughts:
Do I like the top speed, Heck no. Especially coming from a ranger xp800 that I could get to 40mph in a 700ft driveway. But I have signed the papers and it is mine.
I do think it will be a better workhorse than the xp800 was. I used my 800 to move a lot of dirt and gravel and this machine is better for that in several ways. Bigger box, better handling, power dump bed, cab, etc.
It is NOT for taking trips and going hunting where you will need to cover lots of ground or travel along with slower traffic. I wouldn't even say that it would be a good trail ride.
It is louder by far than my xp800. But that 90 amp alternator makes up for that. I have no worries about adding accessories to this beast like I had with the xp800.

If you are a rancher, this machine cannot outrun a cow or a horse. Which to me is sad for all the other thought that went into the machine.


With all of that said. Are your experiences with a properly running machine the same or better than I have seen here?
 

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Discussion Starter · #2 · (Edited)
Did a bit more checking tonight in the garage.

Put the diesel hst up on jack stands and did some tests that I had read about here.

First start idle was at 1350 so it seems to be coming down a bit on that which is good.

Steps:
Engaged the rear diff lock.
In Low gear
Full throttle forward said 14mph with 3780rpms
Full throttle reverse said 7mph with 3810rpms

In High gear
Full throttle forward said 32mph with 3790rpms
Full throttle reverse said 16mph with 3810rpms (I read somewhere that this should be 8. But I don't know where to adjust this at.)

Overall, I think the power is there to get the job done, but I do seem to need some adjustments on the machine to get it right. If I can hit that 32mph on the ground that I see with the machine on jacks, I will be happy because the rest of the machine is just what I wanted.

I wish the throttle control could be seperated from the Hydrostat like the Brutus and Bobcat have. But hopefully, the machine will be able to start moving at a slower pace with lower rpms once the adjustments are made.

Do any of you have the part number for the Brutus service manuals or have any idea what the winch mount plate would be on this beast without the front PTO? I don't see any one that lists this model or the Brutus really.
 

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Cnjdavis,
The mph numbers you got on jack stands should be about what it does on level ground with one person on board. After the command lever fix my Bobcat 3650 does 14 in low (10 up a very steep hill that it used to go up at 2-3 mph before the fix and 30-32 mph in high gear on the level, it used to go 25). It used to struggle to go 25 mph, now it cruises effertlessly at 25 mph.
http://www.egimotors.it/egimotorspa...-10-hydrostatic-drive&id=90:brutus&Itemid=104
This used to be a link for all the brutus service manuals, but it doesn't seem to work now.
 

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Discussion Starter · #6 ·
That is good news then, thx. I wouldn't say that getting to 24 was effortless on this one by any means. It sounds like it is adjusted better than some have gotten from the dealers, so I am thankful for that, but that extra 6-8 mph will make a difference to me around the lease and pastures.

I saw someone posted a photo of the command arm that seems to be an issue, but I can't seem to locate it on mine. I suspect it is under a cover just behind the Hydro pump but I haven't opened it up yet to look. I would rather have the team tech tips in front of me before I touch that or let the dealer correct it.

The Manufacture date on this unit was 3/14. I read that the 14s shouldn't need it, but I am willing to try it to get that extra power and speed.
 

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Have service manuals, will trade for service bulletins

At this point, the only publicly available file is the Owner's Manual. I'd love to find a source for the service bulletins, especially the Command Lever one.

Chapter 1:General Information Checksum: d28b5842f39c1c5ecd17ee4405d93919
 

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Discussion Starter · #8 · (Edited)
Ok, quick update on my machine after some work.

I took some information that was sent to me about the adjustments and started wrenching on the machine a bit. I know some said that new parts were needed but I didn't bother with any of that.

I adjusted the "Travel Control Cable" inside nut 5 more turns back toward the command lever bar. Then tightened the outside nut up against the mounting bracket to secure it. (Needs to be 12lb torqued) It was a matter of trial and error on the jack stands with how much to adjust but I got the machine running much better. I was never able to get it more than the 32 on the jack stands in high range even after the changes, but the low range I was able to back down from the 16 to 8. Once I did this, the machine was dropped off the jack stands and tested out.

Immediately, I noticed that I was able to get the machine moving with much less rpms than it had been before. I can put around the yard using less than 2000 rpm now where before, the machine wouldn't even engage and move with less than 3300. Low range has much more power and high is scooting it along now. I can now echo what ketchn is seeing above. I am able to get the machine to 32-33 on flats and even saw a 35 going down a short slope. I also don't get the sudden jerk stop from the machine after high speeds when I let off the forward pedal that I did before. It slows down gradually as I would expect a non hydrostat machine to do.

Overall, the changes were minor but improved the machine response and speeds pretty well. Would like to get the 40mph that the 2015 HST models are touting, but maybe in time we can isolate that and upgrade ours with the same tuning. I doubt that the hydrostat has changed much. Just the engine would be my guess to meet emission standards.

Also did some other upgrades while I was at it. Replaced the front bumper with a Extreme metal products bumper (Model for the 2013-2014 XP 900 ranger fits) and added a Superwinch Terra45 for those days that the mud wins. For those that have the Brutus NonPTO, maybe this info helps.

Just a couple of photos of the changes.

Sorry for the sideways photo, doesn't look like this on my PC.
 

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Something else that points to a throttle control setup that is more complex than we might think, is this.

When I first test drove a Brutus my instinct was to rev up the rpms manually like a tractor then use the treadle to move. I didn't realize that the treadle also controlled the throttle and that the manual throttle was only for PTO use. However I notice that with the rpms up manualy, no pto engaged, when I would start to move using the treadle the rpms would drop. Obviously the two throttle control methods interact and may interfere with each other. There's no reason for the treadled to cause the rpms to drop when moving over flat ground when the throttle stick is revved up! And if it does whats to stop it from doing so when you need actually need the power. And does engaging the pto stop this negative interaction. One way to test would be to wait for the problem to appear then engage the pto, rev the engine manually and see if the rpms drop or remain constant as you begin to travel again.
 

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My machine has. Top speed of 20 in high range , can i get a picture of the control arm and adjustment nut ? I would like to fix this problem also .
 

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Hi guys,
Looking for the info to increase mph on my Brutus, it's a bit slow and I see you guys seem to have a diy fix for it.
Any photos please.
Regards
Stephen

Scotland UK
 

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I would love to see how the brutus would do with a turbo.
A turbo won't do much good without modding the hydrostatic pump. The pump maxes out at 7.6 GPM and 5004 PSI. It's probably no coincidence that equates to about 24.7 HP. You could connect it to a 100HP engine and you'll still only get 24.7 HP out. I can get mine to bog the engine at full forward command if I max out the tension on the command lever HP spring, so I would see some gains with a turbo, but probably not enough to make it worthwhile.

The pump appears to be a DDC20 pump that's stroke limited. The DDC20 flows about 19 GPM at maximum swashplate angle of 18 degrees. The Brutus pump has an internal stop at around 13 degrees. If that stop can be removed the pump is capable of around 60 HP. If I can build up the courage to tear my pump apart and get a few more degrees of swashplate angle, it will be worthwhile to turbocharge it.

I think there are considerable gains to be had from changing the way the hydraulic motor displacement is controlled. Polaris is using a two speed shift valve controlled by the ECU based on travel speed. It's a fine system but it doesn't account for load. I think a pressure compensated shift valve would be a better solution. Something that would vary the displacement of the motor to maintain around a 3500-4500 PSI. I'm going to play with that before I get into the pump.

Hi guys,
Looking for the info to increase mph on my Brutus, it's a bit slow and I see you guys seem to have a diy fix for it.
Any photos please.
Regards
Stephen

Scotland UK
You should probably get ahold of the service manual and go through the adjustment procedures. Does your machine have the updated command lever? If it does and it's properly adjusted you're not going to get much more out of it without some serious work, see above.
 

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I did a little more research and discovered some errors in my previous post. The pump is a Sauer Danfoss DDC20. It's not stroke limited like I previously thought, it can do 18 degrees in both directions. The Polaris linkage limits the travel in reverse only, it will supply the full 19 GPM in forward if adjusted properly, and this is confirmed by doing some calculations with travel speed, motor displacement, and gear ratios. The 7.6 GPM number came from the service manual, that must be for the gear pump that operates the other hydraulic functions. I'm still trying to figure out why it doesn't lug the engine down more than it does, I assume the combination of motor displacement and gearing don't allow it to build up max pressure and flow at the same time. Need to think about this some more.
 

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Discussion Starter · #18 ·
Good info Interceptor, thanks

I haven't done much with mine throughout the year other than general yard work which is great for it. But when I get it out on the open road it's like riding the back of a tired turtle. Back around Feb. Was able to travel with it around some large farm plots and I really missed my Xp800 gas engine. It got the job done and the heater was nice, but I really got some extra time to take in the scenery. lol...

I did max it out on long straights at 28 and that is all it had.
 

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I've only had the Brutus for 9 days but we've already decided we're not going back to a Ranger with belt drive. We have a Ranger diesel with the same Yanmar engine and a CVT. We have a 1/2 mile driveway with a steep hill, we use the Ranger/Brutus to run back and forth to collect the mail, take out the trash, etc. The Ranger will do about 25 mph up the hill, Brutus can only do about 10. I'm hooked on the HST, it works so well, I'm just determined to get a little more hill climbing speed out of it.

The treadle pedal is directly connected to the command lever, when you push the pedal the command lever moves. The command lever is connected to the pintle lever through a spring they call the HP spring. The pintle controls the pump displacement. Under light loads the pintle and command lever move together. As load increases internal pressures cause the pintle to push back on the spring, the spring allows the pintle to move backwards without the treadle or command lever position changing. The purpose of the spring is to prevent lugging of the engine, it automatically decreases pump displacement while maintaining maximum throttle. The 2013 service manual shows a command lever/spring with no adjustment. My 2013 has a different lever than shown in the manual, it has an adjustment for the HP spring. I assume this adjustable command lever is a result of the update we've heard about. When my Brutus was delivered it was very sluggish, it would rev up to governed speed but just not go very fast. After adjusting the spring for maximum tension I get much quicker acceleration and better hill climbing, but if I try to push it too hard I get some engine lugging and have to back off the pedal to manually decrease the pump displacement. The spring should be adjusted as tight as possible without causing the engine to struggle. I would suggest tightening it all the way down, then backing off until the engine can maintain maximum rpm on the steepest hill you will encounter. It will take some trial and error. This of course is done only after the travel control cable and throttle cable adjustments have been made.
 

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Great info. Will the stock pump support more speed (per your updated post on the SD brand pump)? Would love to see 40 mph light with no attachments and ability to climb better while working. I just don't think Brutus needs to be the 65 mph screamer that the Ranger 900 is.
 
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