Using 1000 rpm hydraulics

[Renze]

Hi folks,

I have been annoyed about the poor performance of my 5245's hydraulics on the loader, because the oil pump is bad.

Yesterday i freed the 540/1000 rpm PTO speed selector lever with WD40 and a pipe (it was stuck when we bought it 6 years ago, and the previous owner probably had'nt used it either)

Since now, my oil pump is running at 1000 rpm, what would give me 60 instead of 33 liter per minute..
The loader lifts more than twice as fast, and a hundred kilos more... I can still notice that i can lift more at 1500 engine rpm than at 1000 rpm (imagine that i had to go to full revs at 540 rpm to get anything off the floor)

I still want a new pump, but the lifting speed is just awesome at 1000 rpm. The pump just seems to howl a bit.


Do you guys use the 1000 rpm PTO to increase lifting performance on loader tractors, and are there any cases of overheating oil or excessive wear on the pump ?

 

[MADE IN BRNO!]

RENZE, IT WONT DAMADGE ANYTHING BECAUSE HYDRAULIC PUMP RUNS AT 1000 RPM ANYWAY WHEN YOU ARE USING PTO IN 1000 RPM SO IT WONT BREAK I THINK MAYBE YOUR HYDRAULIC OIL FILTER IS BLOCKED? THIS IS THE PROBLEM SOMETIMES WHEN LOADER WONT LIFT

 

[Renze]

Yes i know, but then the oil returns directly and doesnt travel through the loader valves..

Which filter ? the one right in front of the cab or the one next to the oil pump under the diff housing ?

 

[MADE IN BRNO!]

WELL RENZE, YOU HAVE TO CHECK BOTH? 69) IM GUESSING THE ONE NEXT TO THE PUMP IS THE OUTLET (FEED) AND THE ONE UNDER THE CAB IS THE INLET (RETURN)??? ITS PROBABLY THE OUTLET FILTER NOT LETTING OIL OUT OF THE PUMP???? OR IT CAN ALSO BE THE INLET NOT LETTING OIL IN TO THE PUMP??? SO YOU HAVE TO CHECK BOTH UNLESS YOU HAVE X-RAY EYES!!

 

[MADE IN BRNO!]

SORRY RENZE! ITS ME AGAIN!! I FORGOT TO MENTION SOMETHING!!69) IF THE LODER LIFTS UP THERE IS NOT MUCH WRONG WITH YOUR PUMP? IF THE LODER OR REAR LINKAGE WONT MOVE THEN ITS THE PUMP GUARANTEED BUT YOURS DOES LIFT? WITH LOTS OF POWER? IF SO THEN PUMP IS FINE!

 

[lspringeradelphianet]

The filter under the differential is a screen and powerful magnet in the oil pickup feeding the pump. The cartridge filter I believe is in the return line that dumps oil back into the case.

See pictures of the pickup filter and the pump at:

http://www.farmphoto.com/photography/message.asp?dsply=all&mid=226018&gkp=

 

[markku]

The hydraulic system is not actually designed for continuos working for 1000 rev pto That is not problem if you use it sometimes and short periodes, But you should not use hydraulics long time with high engine revs.

So i cant see any problems using it for loader. And if you loader lift more dont wonder it. It is because main preussure valve is for 35 litres/minute flow and pump gives 55 litres/minute SO IT MEANS all oil cant pass the valve as it should! And the preussure raise up several bar

Now you perhaps understand why you should not use hyraulics via 1000 rev pto continuosly

This is straight from 7745 manual "It is allowed to use 1000 rev pto ONLY when it is needed for rotating machines transmission, otherwise you should keep 540 pto connected"

 

[Renze]

It just works nice, loading muck at 1200 engine RPM...

 

[treaney]

Do you guys use the 1000 rpm PTO.....excessive wear on the pump ?

Wear is proportional to the square of the speed. So doubling the driven speed from 540 RPM to 1,000 RPM means that you will have 4 times the wear at 1000 RPM that you would have had at 540 RPM.

Tom

 

[Renze]

Tom, forces caused by mass inertia are squared when the speed is doubled. like the ecceleration/deceleration forces on a piston of an engine, traveling from lower to upper dead end.

With ball bearings, the calculation is linear, doubling the speed halves the life. I guess in oil pumps it's somewehere inbetween those ? ???

 

[brian_lofthouse]

Hello all,
It should not be a problem using 1000rpm for the pump,
I use 1000rpm all the time when using our timber crane and have for years now with not one problem, it moves fast even just ticking over, unlike the slow countys pump.
Popeye I would not have thought such a small pump could do so much work it was good to see what it looks like.
Bye...