Valve leak down

Spiffy · Jun 8, 2006

Quick connectors for the test gage! /forums/images/graemlins/cool.gif

I've thought about Teeing in tranducers to several critical areas (PTO, Lift, Tram Pump Fwd & Rev, Charge Pump), then putting a dial selector and a display on the dash.....but just never get around to it. /forums/images/graemlins/crazy.gif

Spiffy · Jun 8, 2006

Quick connectors for the test gage! /forums/images/graemlins/cool.gif

I've thought about Teeing in tranducers to several critical areas (PTO, Lift, Tram Pump Fwd & Rev, Charge Pump), then putting a dial selector and a display on the dash.....but just never get around to it. /forums/images/graemlins/crazy.gif

J_J · Jun 8, 2006

Now that would be handy to have. Just the other day, I saw a digital gage for hydraulic pressure, but it was not cheap.

J_J · Jun 8, 2006

Now that would be handy to have. Just the other day, I saw a digital gage for hydraulic pressure, but it was not cheap.

Spiffy · Jun 8, 2006

Yeah, those digital hydraulic analysers [especially the ones with pressure and flow rate] are not cheap; I was lucky enough that my FIL had borrowed one about the time I was playing with my pumps last winter.

I have seen individual pressure transducers sell cheap on Ebay though. Even at that, I'm sure the nickles and dimes would add up faster than I'd like to imagine! /forums/images/graemlins/tongue.gif /forums/images/graemlins/grin.gif

Spiffy · Jun 8, 2006

Yeah, those digital hydraulic analysers [especially the ones with pressure and flow rate] are not cheap; I was lucky enough that my FIL had borrowed one about the time I was playing with my pumps last winter.

I have seen individual pressure transducers sell cheap on Ebay though. Even at that, I'm sure the nickles and dimes would add up faster than I'd like to imagine! /forums/images/graemlins/tongue.gif /forums/images/graemlins/grin.gif

Barryh · Jun 8, 2006

This is an interesting thread. A lot of good advice here, something I will do when my PT gets some age on it. Right now everything is still brand new. I subscribe to the don't fix it, if it's not broken school of thought. It will be nice to come back to these discussions at a later date. As for the oil, my manual say's the same thing. 10W40 in the manual 5W30 on the tank.

So you see a big difference using 20W50 when you changed out. I will have to consider that. Guess there would be no added pressure according to J.J with the thicker oil. I would think it would be harder on the pumps, especially during colder weather?. Since I will be going to a 6 ply tire soon, I could sure use the extra torque.

Barryh · Jun 8, 2006

This is an interesting thread. A lot of good advice here, something I will do when my PT gets some age on it. Right now everything is still brand new. I subscribe to the don't fix it, if it's not broken school of thought. It will be nice to come back to these discussions at a later date. As for the oil, my manual say's the same thing. 10W40 in the manual 5W30 on the tank.

So you see a big difference using 20W50 when you changed out. I will have to consider that. Guess there would be no added pressure according to J.J with the thicker oil. I would think it would be harder on the pumps, especially during colder weather?. Since I will be going to a 6 ply tire soon, I could sure use the extra torque.

Barryh · Jun 8, 2006

Whether the leak down happens over minutes hours or weeks, I don't see any difference in safety. 

Your right but, I must admit it's nice when working with heavy objects, to be able to take things in and out of the bucket, or off of the forks with the machine off that is. Guess I need to constantly keep in mind sudden let down in pressure could result in a broker leg or worse. Good topic for safty concerns.

Barryh · Jun 8, 2006

Whether the leak down happens over minutes hours or weeks, I don't see any difference in safety. 

Your right but, I must admit it's nice when working with heavy objects, to be able to take things in and out of the bucket, or off of the forks with the machine off that is. Guess I need to constantly keep in mind sudden let down in pressure could result in a broker leg or worse. Good topic for safty concerns.

J_J · Jun 8, 2006

Any oil at cold temperatures will not flow as fast as when hot, and on a driven pump, the oil will heat up quickly. Pressure in a system is caused by some kind of resistance to the pump, whether it is a closed valve, a cylinder, or a motor. The pressure will vary as you use the system. An example of a system with the pump running max rpm and very little pressure, would be the PTO pump. When not in use, the fluid is pumped through the on/off valve and back to tank. Very little pressure would be generated. Now if the PTO valve were switched on, and you had a hydraulic motor is the circuit, the motor becomes the resistance, and the pressure will develop as you control the flow. In my case, I use a lever to vary the PTO speed. Some of you have a solenoid to activate the PTO, and you can't regulate the speed except by changing the speed on the engine. I was surprised at the pressure on the lift arms when raising them with no load. My gage read very low pressure. As soon as you pick up a heavy load, the pressure climbs up close to max. You will also get spikes that may go above the rated pressure when things are suddenly changed.

J_J · Jun 8, 2006

Any oil at cold temperatures will not flow as fast as when hot, and on a driven pump, the oil will heat up quickly. Pressure in a system is caused by some kind of resistance to the pump, whether it is a closed valve, a cylinder, or a motor. The pressure will vary as you use the system. An example of a system with the pump running max rpm and very little pressure, would be the PTO pump. When not in use, the fluid is pumped through the on/off valve and back to tank. Very little pressure would be generated. Now if the PTO valve were switched on, and you had a hydraulic motor is the circuit, the motor becomes the resistance, and the pressure will develop as you control the flow. In my case, I use a lever to vary the PTO speed. Some of you have a solenoid to activate the PTO, and you can't regulate the speed except by changing the speed on the engine. I was surprised at the pressure on the lift arms when raising them with no load. My gage read very low pressure. As soon as you pick up a heavy load, the pressure climbs up close to max. You will also get spikes that may go above the rated pressure when things are suddenly changed.

KentT · Jun 8, 2006

( So you see a big difference using 20W50 when you changed out. I will have to consider that. Guess there would be no added pressure according to J.J with the thicker oil. I would think it would be harder on the pumps, especially during colder weather?. Since I will be going to a 6 ply tire soon, I could sure use the extra torque.
)
That's why the use of synthetic instead of Dino. 15W50 synthetic is likely no "harder" to pump when cold than 10W30 or 10W40 dino oil. The real difference is when it is hot... which is EXACTLY what you're looking for. With no oil cooler, I'd think the difference would be even more noticeable on a PT-180... but I have no firsthand experience. /forums/images/graemlins/wink.gif

KentT · Jun 8, 2006

( So you see a big difference using 20W50 when you changed out. I will have to consider that. Guess there would be no added pressure according to J.J with the thicker oil. I would think it would be harder on the pumps, especially during colder weather?. Since I will be going to a 6 ply tire soon, I could sure use the extra torque.
)
That's why the use of synthetic instead of Dino. 15W50 synthetic is likely no "harder" to pump when cold than 10W30 or 10W40 dino oil. The real difference is when it is hot... which is EXACTLY what you're looking for. With no oil cooler, I'd think the difference would be even more noticeable on a PT-180... but I have no firsthand experience. /forums/images/graemlins/wink.gif

Barryh · Jun 8, 2006

On the synthetic verses dino, those were exactly my thoughts knowing I have no oil cooler. The only thing undecided as of yet is Amsoil over Mobil 1 and the cost. Anywho, I know this has been hashed out before. I don't want to take away from the valve topic. Thanks for your insight on the difference in performance.

Barryh · Jun 8, 2006

On the synthetic verses dino, those were exactly my thoughts knowing I have no oil cooler. The only thing undecided as of yet is Amsoil over Mobil 1 and the cost. Anywho, I know this has been hashed out before. I don't want to take away from the valve topic. Thanks for your insight on the difference in performance.

Barryh · Jun 8, 2006

Thanks for clearing that up. More good information to log away. /forums/images/graemlins/smirk.gif

Barryh · Jun 8, 2006

Thanks for clearing that up. More good information to log away. /forums/images/graemlins/smirk.gif

Spiffy · Jun 8, 2006

( Whether the leak down happens over minutes hours or weeks, I don't see any difference in safety. 

Your right but, I must admit it's nice when working with heavy objects, to be able to take things in and out of the bucket, or off of the forks with the machine off that is. Guess I need to constantly keep in mind sudden let down in pressure could result in a broker leg or worse. Good topic for safty concerns.
)

Exactly! Unless the leak down occurs over seconds (in which case hydraulic control would be really annoying), I can't see where they can claim the leak down as a safety issue. So I'd like to be able to have the bucket or forks where I left them - even if I want to finish unloading after lunch!

Spiffy · Jun 8, 2006

( Whether the leak down happens over minutes hours or weeks, I don't see any difference in safety. 

Your right but, I must admit it's nice when working with heavy objects, to be able to take things in and out of the bucket, or off of the forks with the machine off that is. Guess I need to constantly keep in mind sudden let down in pressure could result in a broker leg or worse. Good topic for safty concerns.
)

Exactly! Unless the leak down occurs over seconds (in which case hydraulic control would be really annoying), I can't see where they can claim the leak down as a safety issue. So I'd like to be able to have the bucket or forks where I left them - even if I want to finish unloading after lunch!