i'm baackk

[johara1]

Re: i\'m baackk

mr, now i started to fabricate the changes to the attachments, just put on a cutting edge. 40.00 steiner 1/4 thick high carbon steel. now i'm making skids that are adj. for height, then add stiffners to the bucket.terry said it would bend if you do a lot of prying with it. then the ripper, that should do for now /forums/images/graemlins/tongue.gif

 

[ernemats]

Re: i\'m baackk

What all did you get for attachments? I'm glad you had a good trip going down to get your tractor , it is a nice but long trip but worth the while. They treat you good and let you try what you want.. It would be nice if all pt purchasers could make the trip.

 

[Kaon99]

Re: i\'m baackk

Here's a dumb question about the new 2003 pt425: If the 2003 pt425 has stronger wheel motors and nothing else has been changed, won't there be less power for the mower on hills ? It seems to me that unless the total power output has somehow been increased that somthing has to give.

Since I bought one of the last of the old pt425's, I was a little put out that Power-Trac keep the new model pt425 a secret. However, I have tested my pt425 on the slopes on my property (15-20 degree slopes) and I definitely have all the wheel power I need (without the mower going). When the grass starts to grow in the spring I will do the test again with the 60" mower on and report back. I will be interested to hear how the new pt425's do on slopes with a 60" mower going.

So far for me, wheel torque has not been an issue. In the work I have done pulling logs out of my lake, I lose power from wheel spin and not lack of pulling power.

Since there is no local dealer service for my pt425, it is comforting to know a bunch of guys (like Mossroad) have a machine exactly like mine. It is a small consolation, I guess, for missing out on a beefier machine.

Ken in Mississippi

 

[Charlie_Iliff]

Re: i\'m baackk

<font color="red"> If the 2003 pt425 has stronger wheel motors and nothing else has been changed, won't there be less power for the mower on hills ? </font>

Certainly seems logical, unless they slow down the ground speed or the motors are significantly more efficient, which seems unlikely.

 

[MossRoad]

Re: i\'m baackk

So, we have a base 25HP comming out of the engine. The pumps for the mower and wheels are seperate. I figure(and that's asking alot) that as long as the wheels aren't loading down the engine, the mower won't be affected. Once the wheels start loading the engine down, then there will be less HP available to drive the mower(PTO) pump OR if the mower starts loading down the engine, there will be less HP available for the wheel pump(works both ways, right?).

So, how do they get more torque out to the wheel motors without affecting the top speed of the tractor? Different motors? More efficient motors? If someone could come up with the old motor model numbers and the new motor model numbers we could figure it out. Did someone say that they are manufactured by WHITE? If so, here is a link to their website. We can request a free catalog.

Or, if you don't want specifics, the next time someone visits Power Trac, ask them, without specific numbers and such, to explain how the motors can provide more torque, yet maintain the top speed.

 

[Anonymous Poster]

Re: i\'m baackk

Charlie - your right they do it by slowing down the ground speed - with larger displacement wheel motors - there is always a trade off - otherwise you would have to change the pump - the motors could be more efficient also - I think the series I have on the 425 get some blow by when running hot and put under stress like climbing a steep hill full throttle with the mower running - I notice that in the cold pushing snow the wheel motors will stall the engine before reaching a limit - but not in the summer climbing steep hills while mowing-
I asked Terry if they changed the pump and he said no
so i said that the only other option is to increase displacement which means less speed and he said that is what they did - he mentioned 7mph - I would guess 6-7 - to get a really get a significant change in torque vs mine - rated at 8mph -

Maybe there are different pump settings that can be used as well - I think the Eaton wheel motors on the 1430 and 1845 etc - are just superior motors - they seem much stronger and are alot more quiet.

As far a figuring out - specs - if everyone recalls last fall - I went around and around on this in one or two threads - I even spoke with White several times - it always led back to PT - White told me that we can't try and fish our way through and back into the specs based on advertised ground speed and tire size - He told me to just call PT and get all the model numbers and specs for the White wheel motors and Eaton pump

I tried again - and got nowhere with PT - thats when I got frustrated and just bought the 1845 - what frustrates me is that they really didn't seem to think the torque on steep hills was a problem - and now I realize that they were aware and in fact designing a fix which they incorporated in this years model - would not have changed my mind on the 1845 - it just would have been nice to have this information in my decision making process

Oh well - They are how they are

 

[Charlie_Iliff]

Re: i\'m baackk

Ed:
I have resigned myself to PT's secrecy. They simply will not say what they're working on, although in November Hans, John Coxon & I were given a rare glimpse of a possible fix for the chaff ingestion. I can't fault the policy, since it's purely their choice. We'd all be a bit more comfortable, however, if they'd simply say "We're not going to tell you that," instead of vague promises that we'll hear something, folowed by silence.
The trick, I suppose, is just not to ask questions unless they bear directly on warranty work. That way, you won't expect answers or be disappointed.
Nah - that wouldn't fit our developing PT-User profiles. Keep bugging them.

 

[davesisk]

Re: i\'m baackk

Nah - that wouldn't fit our developing PT-User profiles. Keep bugging them.

Charlie, I couldn't agree more. If enough people ask for something or point out the same problem, they are much more likely to respond. "The squeaky wheels gets a greasin'", so they say!

Dave

 

[Anonymous Poster]

Re: i\'m baackk

I'm relatively confident that the wheel motors on the last year's PT 425 and my PT 422 are White RS Series Code 200 12.5 cubic inch displacement motors. I note that the back of the wheel motor housing on mine has "Roller Stator" imprinted on it. This is a trademarked term for White - so I'm sure they are manufactured by White. Visually they are identical to the RS series shown at the White web site. I actually pulled off a front wheel and took dimensions on one of the motors. The length dimension (6.29 inches) indicates that it is the 12.5 cubic inch (code 200) unit.

Some back-of-the-envelope calculations show that with the maximum torque these motors are rated at (3050 lb-inch) and assuming the tractor, rider, and attachment weigh approximately 1600 lbs. the tractor can only climb hills up to approximately 20 degrees. I believe someone else calculated about the same number in a previous post which I can't find right now.

I assume that Power Trac is attempting to improve the torque for hill climbing and also to beef up the lateral load capability with the new wheel motors. The way they could improve torque without changing pump displacement or speed is to increase the relief valve pressure setting. My guess is that the new wheel motors have the same displacement but a higher pressure rating. Although I can't determine the specific pump used for the wheel drive, most variable displacement pumps I've seen are rated at 3000 psi. Using the old wheel motors the reliefs must be set at 1750 to 2000 psi. I'm assuming that with the new wheel motors they upped that setting to a point still within the capability of the pump to provide additional torque.

By the way, I agree that no matter what they did to the motors, it is still going to take approximately the same engine horsepower to climb the same hill at the same speed. I think they were just trying to overcome the problem with the wheel motor reliefs lifting while the engine still had power to use.

 

[johara1]

Re: i\'m baackk

they are white,the new ones have more volume=more torque.this will give you more power to the mower. the engine doesn't have too work as hard with the travel. /forums/images/graemlins/smile.gif

 

[Anonymous Poster]

Re: i\'m baackk

this is probably what they did - the old ones as well as the new ones are White - Terry told me so - I just didn't know what series / displacement - you can tell just by measurements? - I wonder what series the new ones are - so do you change only the relief - or the actually system operating pressure settings?

I do think they increased the displacement as well because Terry told me so - he said that max speed dropped to around 7mph -

I recall last year that he told me that the pump pressure is pre set from the (Eaton) factory and that you could not change it - and it was set basically at maximum operating pressure - the reason I asked him was because I was considering increasing the operating pressure if I could find out the specs and settings on the machine - but was not able to obtain this info - so I would be basically operating in the dark and finally decided to leave it the way it is and buy the 1845.

I spent hours going through Eaton catalogs trying to figure out the pump model so I could get the specs from Eaton - I never was able to identify it - and what numbers I got off of it didn't mean anything to the Eaton people I spoke with on the phone

- They said - "why don't you just call the tractor Company and ask them for the Eaton model number - that would save you so much time" - Now theres an idea

No - I told them I just love the hunt - that would spoil the fun


Well it would be great to identify all this stuff - old wheel motors model number, displacement, new ones
and the pump as well as all the settings - that would just be great -

 

[johara1]

Re: i\'m baackk

i would check the rpm on the engine,free and under load this may have a lot to do with the problems.

 

[Anonymous Poster]

Re: i\'m baackk

I actually never did that - checked rpms - but I can just tell that the engine is operating properly - it has plenty of power - and when I am cutting at full throttle in the summer on these hills (20 - 22 degrees ) - I know the rpms are up over 3000 because I can hear the engine racing - it just seems that the heat of the oil, conditions, slope - mower running - etc - all together degrade the peformance of the wheel motors (or the pump -but I think it is the wheel motors - the sound is a high pitched whine) everything together add to heat and stress

and then the machine shutters when i crest the steepest part of the hill) which I guess is the reliefs lifting - it is just the limits of these wheel motors - It did climb and make the hill all summer while cutting - I just felt that i was stressing the machine more than I should have been

In fact my friend who is heavy equipment operator (40 ton excavator) was over when I was cutting this really steep part -he told me to stop and check the oil - as his machine makes that noise when it is low on oil - of course the oil level was fine as was the filter - etc. - so he thought that maybe the oil was getting too hot and the machine is losing efficiency - he also wondered why it uses 10w40 instead of hydraulic oil (with antifoam agents)

I told him - of course that I guess they just designed it to use 10w40 and that I thought that I was just running up against the limits of the machine .

Which is exactly what I still think and they confirmed with the redesign - Terry told me that under my conditions - my 425 is basically spent after 18- 20 degrees

Remember - 20 degrees is very steep

 

[johara1]

Re: i\'m baackk

this is on reason i'm going to syn. oil it disapates heat better.easer on it in the winter and the summer.
i also run equip. the d11's were loosing final drives a lot , by changing to syn. oil they doubled the life of the finals. the engines also gain life with syn. oil /forums/images/graemlins/laugh.gif

 

[Charlie_Iliff]

Re: i\'m baackk

<font color="red"> this is on reason i'm going to syn. oil </font>

Even with the price you mentioned earlier, 10 gal of synthetic will pinch a bit.
I'm going to Amsoil oil for the engine, but my 20 gal hydraulic oil will stay as delivered for a while longer.

 

[Anonymous Poster]

Re: i\'m baackk

Is it easy to change all the hydraulic oil? - don't you have to get every bit out ? - I assume you can't have any of the old oil in the system if you go to synthetic

Do you know the difference between regular oil and say Castrol heavy duty hydraulic oil like the stuff they use in big machines? - that stuff is pretty expensive - I remember because my friend blew a hose while working here last summer - and I had to run out and pick up several pails
for him - real expensive

Do you think that with regular 1040 it gets thin and you get blow by through the tolerances?

You think the synthethic will reduce that?

 

[Charlie_Iliff]

Re: i\'m baackk

Ed: Most if not all of the synthetics say they are compatible with fossil oils, so it isn't necessary to get every last drop out. I have seen recommendations in various applications just to start adding synthetic when needed, since "some synthetic is better than none." If you search the web for "synthetic oil" you'll probably come across that article.
According to what I've read, the synthetics are better in extreme cold, because they don't thicken as much, and better in extreme heat because they maintain lubricity. Within normal operating ranges, however, their viscosity is as rated, and there isn't as much variation from fossil oil performance. It's hard to predict, therefore, whether in hot operation you'd get more effective power transmittion in the hydraulic systems.
I've seen a number of people saying they got easier cold starting, but not much comment on hot weather power when the synthetics are used in hydraulic systems. In fact, most tests suggest no change in engine performance with synthetics, but longer change intervals and reduced wear over time.

 

[johara1]

Re: i\'m baackk

charlie,
the use of syn. oil almost doubled the life of the 3508 engines, from 10000 hr's to 18000. we also had to turn the idle back, this i think is due to less friction. this was a average of 12 diff. d11 dozers over the span of 40000 hrs each.
what i'm driving at is,ever little bit helps and less wear on the pumps and wheel motors.

 

[Charlie_Iliff]

Re: i\'m baackk

Johara1:
I wasn't suggesting that synthetics don't do good things, just that it would be hard to predict any improvement in power transmission in the hydraulic system, since most systems do not experience the high temperatures of engine service. Although the promotional literature for synthetics often touts performance increases, they are most often referring to lubricity at low and high temperatures. Dyno testing in normal ranges has seldom shown significant power increases, although some amount may be observable. The real benefits are reduced degradation over time, reduced evaporation, better additives to handle contaminants, etc.
There is certainly no doubt that particularly in hard service, synthetics extend engine life and aren't as expensive as they seem because change intervals can safely be extended. For me, however, at 150 hours per year, I would have to live to be about 216 years old to wear out a pump or motor even with fossil oil, and if I trash it due to damage or contamination, synthetic won't save it, so for now I'm saving my $400 in the hydraulic system. It is Amsoil for the Deutz, however.

 

[Rocketman]

Re: i\'m baackk

As you guys know, contamination and heat are the two main enemies of a hydraulic system.
Contamination can be controlled by using a good quality filter (10 micron or so), changing it often, and keeping the system as tight as possible (leave the filler lid screwed on!).
Heat has always been a problem for the manufacturers - I've worked on this with Eaton. But the real heat issue may not be what you think?????????????? As you change direction of fluid flow (treddle) there is a very serious "instantaneous" spike in temperature and pressure on the high side of the pump. String enough of these direction changes together and you end up with an overheated pump with galling and eventual failure not far behind. I know you are saying to yourself, now Rocketman this is all well and good but what the heck does this have to do with the discussion at hand? The relevance is that synthetics do a superior job in dampening the temperature and pressure spikes – lessening the severity of conditions which induce pump failure. But, true synthetic hydraulic oil can cost as much as $20.00 per quart...now that is going to hurt!. There is a cheaper oil solution that performs much better than all other dinosaur juices (at dampening pressure/temperature spikes) - Mobile DTE26 at about $12.00 or less per gallon. I personally will be changing the hydraulic system's 10W40 motor oil to DTE26 as soon as possible after I get the tractor. For the benefits, synthetics in the engine are a good choice. Clean synthetics in the hydraulics are also a good technical choice and could make your hydraulics a nearly lifetime system.....if you could afford it.