Air in My Hydro oil..2005-TC-30 7308 loader

[Chris527]

Hi gang, been a bit since I had any issues but this one got me pretty concerned. Spring of this year I did the major service, filters and Hydro oil(all new holland). About 200 hours ago.
I did not notice any issues until my neighbor borrowed my tractor and backhoe, I noticed it was LOUD and whining. I checked the oil in the sump later and it was air bound, I thought the backhoe may have had a suction leak, I checked all nothing wet. I went through everything.
I have my blower on now, I check the sump dipstick, about 3/4 between lines so it was not overfull. My garage is not level so I called it good. Warmed it up for 20 mins, out to the sand pile, 5 mins with the bucket , brought it back in, not good. with the foam, it looks overfull, it does settle overnight so I believe this is air and not water. Its not noisy now but its really making foam and I do not want to kill my pumps, its hydrostatic drive, the only circut that noisy is the dump cycle. I went through every inch of lines today and saw nothing wet and it has zero leaks. I do have a slightly bent steel line in the front on the loader but that's been like that for 3 years. I have no power issues but not liking what I'm seeing here.
Any input would be great, meanwhile I will keep looking.

 

[RickB]

Check the hydraulic suction filter for signs of impact. Your neighbor could have hit something and disturbed the filter seal or cracked the filter head casting. If it was cracked in the right place it would be above the static oil level in the housing and not show a leak.

Don't lend your tractor out.

 

[Chris527]

Thanks, will triple check, all looks well under there, I really do not know for sure when this started, If you ck your oil and it look good cold, who would have suspected it was getting air? I could have a defective filter for all I know, I was not in the habit of checking my hydro oil after use. I guess because everything on this tractor is hydraulic and shares a common sump, I will isolate circuits and see what happens. I can Isolate the 7308 loader and run it , also the remote in the back has a valve I can just shut off, this could be anything from a collapsed hose to a leaky filter seal. Thanks for the reply.

 

[the old grind]

An easy way test for water in oil is to apply foam to a 100% polyester rag (vs cotton shown). Oil will wick onto the fibers and water will bead up.

Can we rule out a leaking seal or scored piston shaft allowing bucket drift (once parked or op'ed in 'regen') to draw air in. I'd expect regen might keep air in the dump circuit for a few cycles. What I'm getting at is, how much of the oil is getting foamed? Enough to raise the level to the filler or stick (~ same height) seems like a lot, but what can one do in 5 min with the FEL? (If other functions seem ok .. ?)

So if you operate for a while w/o working the bucket/valve (just raise/lower), what happens? Seems one could tell in 5-10 min from a cold start. Did the borrower ever top up the hydraulic supply? Right stuff if so?

Lol, the times of this and the last post says it took me a half hour to edit this. I guess we were thinking along similar lines to isolate possible sources.

 

[Chris527]

Thanks for the reply, I can get some water test paste and dip my sump, It will turn purple if its water, I have to start someplace, I will disconnect my bucket circuit first, a lot can be going on there, some of those hoses look crappy, I will run it for a time and see whats gets stirred up, hopefully nothing. I also have a rear remote, that I did not use much or at all until mid summer and then the issue started.

 

[Chris527]

So I went to New Holland, talked to the service Manager, he advised me to tighten up all suction clamps, see If I can give the filter a extra nudge, I did all. He also said if that does not work it might be the O-Ring on the suction side line to pump. With 33" of snow I had to run it, it takes about 45 mins to show up( I kept checking). Takes about 2 hours to settle. Waiting for warmer weather to test more.

 

[rodneyn]

I found out the rubber hoses on the low pressure return lines, some of the stub hoses were breaking down allowing for air to enter into the hyd oil. Typically the units failing were sweating oil from them. I replaced the hoses with new and all air issues stopped. Air in hydrostatic is death sentence to the unit over time.