Just blew a hose

[MuncyBob]

Lost the lift hydraulics due to one of the hoses blowing off the coupler. Off to NAPA today to get a new one...questions is, do you bleed the system just as when changing the filter? I'm guessing I'll have to use the lift several times and then bleed?

Looks like this week is PT repair week for me...just received the new fuel pump last Saturday and a friend will be "supervising" my removal of the carb this Saturday. Hopefully no more vapor lock or surging come Saturday afternoon!

 

[tym233me]

No need to bleed the hose ,just make sure your fluid level is good and operate the lift hydraulics a couple times and it will self bleed

 

[KentT]

That's correct...

The only circuit you typically need to bleed is the tram pump. Any of the other hydraulic systems (lift, tilt, aux, steering) all you need to do is operate that circuit a few times.

The only time you'd need to worry about those circuits is if you disconnect the lines between the pump and the tank, so that you've introduced air "in front" of the pump. Then, similar to bleeding the tram pump, just pull the spark plug wires and crank it for a minute or two without starting the engine, then replace them, start the engine, and operate the controls...

Air in a line in front of the pump (any hydraulic pump) can "starve it" and cause damage by metal-to-metal contact without lubrication. The tram pump is especially vulnerable because of the swash plates of the variable flow control -- they are extremely close tolerance -- much more so than the fixed output pumps for the other circuits.

 

[woodlandfarms]

Kent. Your note is interesting because I changed out my hoses that drive the wheel motors,and did nothing to fill the lines with oil, nor prime the pumps.

Wonder if I did some damage (I have not issues but....)

 

[KentT]

Kent. Your note is interesting because I changed out my hoses that drive the wheel motors,and did nothing to fill the lines with oil, nor prime the pumps.

Wonder if I did some damage (I have not issues but....)

The installation instructions for my new wheel motors were to:

(a) fill the motors with oil,
(b) crank the engine over without starting it for one minute -- twice, so not to overheat/damage the starter,
(c) then start it and let it idle for about 15-20 minutes before putting any loads on the wheel motors (i.e. driving it), then slowly operate the controls to ensure all the wheels start to turn at the same time.. They recommended putting it on jackstands for this step.

IMO, all these steps were intended to get the air out of the circuit before putting the motors under load... air will compress and will form bubbles and eventually "foam" as those bubbles pass through the motors or pumps. The more pressure on the system, the more the air compresses, and the more foam you can get as a result of it...

I doubt you did much if any significant damage to your wheel motors, since they should've been full of oil to begin with, but you likely didn't "do them any favors" either.

Did you let the motor idle for a few minutes before driving the tractor? This would have given those air bubbles the opportunity to get back to the tank before putting pressure on the system...

 

[woodlandfarms]

Oh yeah. Idled for a while as I remember. Was totally freaked out about oil leaks so I was double checking every fitting under pressure.

 

[MuncyBob]

The mess from the blown hose got me to finally clean the hose area in the front before the new hose install. Now I see I have several hoses leaking slightly....seems the hoses are crammed into areas so tightly that the bend near the connectors has been stressed and 3 hoses are leaking there. I think I will replace them before they too burst apart. I'm thinking replacement with 90 degree elbows may solve the stressed connector problem. Anybody notice this on their hoses?

 

[J_J]

Anytime you open the closed loop system, you should bleed the wheel motor/pump circuit. thoroughly. The wheel motors have to be turning to pass the air and fluid back to the tram pump bleed port. Sitting at idle will not bleed the wheel motors

Actually, if you do not bleed the system at the tram pump, and since the wheel motor circuit is a closed loop circuit, the air in the system will just circulate around until some of it goes into the case drains on some of the wheel motors, and then to tank. Some of the air in the pump may be sent to the case of the pump along with charge pump excess fluid which is used to cool and or flush the pump case, and then to tank.

 

[woodlandfarms]

Farmall

One thing I want to mention, and the geniuses here will clarify, there are at least two different types of crimped connectors for hoses. One is longer than the other. PT uses the shorter version and designs for it. NAPA in our hood uses the longer version, and I have a few hoses from them on the shelf I cannot use because of the length issue. I ended up going 30 miles away to a different shop that had the shorter hose connectors.

 

[MuncyBob]

Farmall

One thing I want to mention, and the geniuses here will clarify, there are at least two different types of crimped connectors for hoses. One is longer than the other. PT uses the shorter version and designs for it. NAPA in our hood uses the longer version, and I have a few hoses from them on the shelf I cannot use because of the length issue. I ended up going 30 miles away to a different shop that had the shorter hose connectors.

Yep, these are the NAPA hoses. I think it will be cheaper if I just have them remove the longer connectors and put on the elbows. But the leaks I observed are all from the original hoses and it just seems to me that the way these hoses are extremely bent puts too much stress where the hose meets the connector. I have just under 400 hours on the tractor and did not expect to see this many leaks at this time. Granted, they are very minor leaks but still don't want to be out in the woods when one decides to pop off like the one that just did in my backyard.