Sounds Expensive

[crazyal]

I agree with Homebrew. The PRV is only used when lifting or curling the bucket. If you are trying to drive into something (or dump a big load into the FEL while up) the PRV is not going to release any pressure. It's possible that there is an overload built in for such cases I wouldn't count on it. My case 580K had a bent swing cylinder (16" stroke 3" diameter) from the previous owner thinking he could use the extended backhoe as a tie off to pull a stuck truck out of a ditch. He was pulling on it sideways and had the front bucket down to keep it from spinning sideways. $500 later he called a tow truck.

Sorry to hear how much it's going to cost you Dan. It's why I've been reading these posts for so long now. I want to learn as many "don't do's" as possible before I have to bend over and pay for my big mistake(s).

 

[N80]

I think you guys are right about the PRV, however, maxing out the FEL, as in pushing too hard with the bucket in the dump position, should blow something in the loader pistons or maybe the hydraulic pump. I wouldn't think it would impact the HST itself would it?

I think using the tractor hard really didn't figure into the failure. Not using SUDT probably didn't play a major role either. Busting a filter, dumping all the fluid and keeping on going sounds like more than enought to toast an HST.

 

[crbr]

......Pulling my huge lawn roller in high gear, stopping so suddenly that it bent the roller connect up in a "V" shape.

D@mn... Any pics or a video?

Running her WFO huh? And a sudden dead stop... There has to be a video...

 

[dannydan3]

D@mn... Any pics or a video?

Running her WFO huh? And a sudden dead stop... There has to be a video...

I wish - maybe it would help offset the cost of my sequential dumb *ss attacks. I could host a course on how NOT to treat one's tractor, maybe theres a few bucks in that too. Wow, I'm almost to the $1700!

 

[Volfandt]

Isn't that kindof a yes-and-no also? The PRV only works on a particular circuit when the circuit is in use, so w/ no FEL functions in use, pushing the FEL into undisturbed ground could overload the hoses/cylinders, etc.

Yes & No
I don't have my BX hydraulic schematic with me but if I recall correctly the PRV is in series with the FEL, 3ph & if equipped BH circuit so I would think that any over pressure situation in any part of the series circuit would trip the PRV. Course it''ll probably bust an aged hose or coupling too.

Not using SUDT probably didn't play a major role either.

Theres a reason why Kubota spec's out multigrade in their HST's and like engine manuf's spec out multigrade for their engines, too thick an oil at cold startup/operation can be too thick to properly lubricate those very close tolerances. Over time the lack of proper lubing will wear those parts and those worn parts introduce "fod" into the system. FOD will wreak havoc in the close tolerances of a modern HST....
Course proper warm up of an HST w/straight grade UDT before operating/loading it probably won't hurt over time, but why chance it?

 

[hazmat]

Yes & No
I don't have my BX hydraulic schematic with me but if I recall correctly the PRV is in series with the FEL, 3ph & if equipped BH circuit so I would think that any over pressure situation in any part of the series circuit would trip the PRV. Course it''ll probably bust an aged hose or coupling too.
...

Even if it is the same relief valve, if you are not operating the FEL (for example), the "closed" FEL valve prevents the overpressure oil from getting to the relief valve.

 

[Volfandt]

Even if it is the same relief valve, if you are not operating the FEL (for example), the "closed" FEL valve prevents the overpressure oil from getting to the relief valve.

OK, so if I undestand this argument correctly, the scenerio is that an operator is using his FEL to "jam" into a bank to dig it out and will this harm his hydraulic system, is this correct?
If so, the act of jamming an FEL into anything porbably won't do any harm to teh hydraulic system per se, it may bend a ram, or bucket of even perhaps the mount but if the valve is closed, I don't see the need for the PRV to intervene as theres no additonal pressure being applied to the FEL to jam into the bank, other than the normal pressure's on either side of the double acting ram(s) to keep it in it's particular position at impact. Now if the operator now trys to lift or curl the bucket with the FEL embedded into the bank (or whatever the load may be) and the load is more than it can handle, the FEL will either not move at all -or- the PRV will open, releasing the pressure.
I've heard my FEL & BH squeal the PRV more times than I care to say
Course if a bent ram introduces chips of material into the hydraulic system then they can ultimately damage the HST so I guess it is a yes & no answer

 

[hazmat]

OK, so if I undestand this argument correctly, the scenerio is that an operator is using his FEL to "jam" into a bank to dig it out and will this harm his hydraulic system, is this correct?
If so, the act of jamming an FEL into anything porbably won't do any harm to teh hydraulic system per se, it may bend a ram, or bucket of even perhaps the mount but if the valve is closed, I don't see the need for the PRV to intervene as theres no additonal pressure being applied to the FEL to jam into the bank, other than the normal pressure's on either side of the double acting ram(s) to keep it in it's particular position at impact. Now if the operator now trys to lift or curl the bucket with the FEL embedded into the bank (or whatever the load may be) and the load is more than it can handle, the FEL will either not move at all -or- the PRV will open, releasing the pressure.
I've heard my FEL & BH squeal the PRV more times than I care to say
Course if a bent ram introduces chips of material into the hydraulic system then they can ultimately damage the HST so I guess it is a yes & no answer

You got it. Bottom line - the PRV is only protecting the "active" circuit & it's best to use the machine within it's limits (not at or above).

 

[RonR]

A long time ago, someone posted a pic of a homemade transmission oil filter protector that bolted to the frame and covered the filter. I think I saved a pic of that somewhere and probably will dig that out for my BX. It was basically a piece of metal pipe that went over the filter

If you have a skid plate, it's probably not needed, but this one looked easy to build.
ron

 

[Soundguy]

chalk it up as the cost of doing business.. that and experience. Remember.. not much better experience than bought experience... Bouhgt experience counts as earned experience.. except it costs more...

Also.. keep in mind... at least the rest of the tractor is ok.. that price coulda been alot higher. in the big scheme of things.. 1700$ is stiff.. but not horrible. .. I can't wait till I have to replace the rubber on my NH 7610s... all 4 tires on it are quickly heading to 'bald' That's going to be an unhappy day for me and my credit card!!!.. those rear tires are near as tall as i am...

Soundguy

I wish - maybe it would help offset the cost of my sequential dumb *ss attacks. I could host a course on how NOT to treat one's tractor, maybe theres a few bucks in that too. Wow, I'm almost to the $1700!