b7800 I smell hydraulic fluid

[Stoweski]

Did a search for hydraulic fluid smell tonight. Did this because just this afternoon I was out working with the tractor. I had the FEL moving almost constantly. I started smelling hydraulic fluid and I stopped and got off the tractor. Checked all connections and found no leaks. Went back to work and smelled it a few more times before I stopped for the night. Only thing I heard was a noise coming from the lines on the side of the FEL. Sounded like a vent or possibly air in the lines.

Any chance the air could be the problem? If so how would one go about bleeding it without getting fluid all over the place?

Would be nice if this were a common 'problem'. I have 66 hrs on it and have never smelled this before.

Thanks,
Keith

 

[Soundguy]

The cyls will self bleed.. however.. unles they acted spongy or jerky.. i doubt you had air in them.

Pull the dipstick and look for foamed fluid.. if you find it.. report back.

locate your vent on your machine and see if much of your smell is coming from that area... test by putting a kids balloon over it.. if the smell goes away.. you found the issue... remove the balloon..

soundguy

 

[Stoweski]

The cyls will self bleed.. however.. unles they acted spongy or jerky.. i doubt you had air in them.

Pull the dipstick and look for foamed fluid.. if you find it.. report back.

locate your vent on your machine and see if much of your smell is coming from that area... test by putting a kids balloon over it.. if the smell goes away.. you found the issue... remove the balloon..

soundguy

Well, two more afternoons of working the FEL for a couple of hours each night. The first of the two I smelled the fluid a couple of times. Tonight I smelled nothing. I did check the vent and no fluid was draining. I also checked the level, and looked for foaming, found none. I did, however, notice that the hydraulic fluid level is about 1/4" over the markings on the dipstick. I assume that if the level is too high that it will overflow out the vent. Is this a correct assumption?

I guess all in all the smell of hydraulic fluid is a bit more pleasing that diesel.

Thanks for the reply!
Keith

 

[B2400]

I notice it more when it's warmer, but if I'm working it hard it will occasionally smell that way when it's cold out too. It's normal!!

 

[AMR]

One of the primary reasons I traded my BX23 for a B3030 was because my BX23 leaked hydraulic fluid from the vent, particularly on those August mowing days. It turns out that the dealer thought that I was using the machine on a slope steeper than the machine was designed for. When I mowed this slope the fluid would start bubling out of the vent. Not a lot, just a few drips, but it is a smell that I can't get rid of, nasty. Plus I have about a hundred half dollar sized dead spots in my lawn that I am patching. My short term fix was to mow that section of my lawn last and stuff paper towels around the vent just before I did it. My long term fix is my B3030 and thankfully it doesn't have this problem.

 

[Buckeyeman]

I have a B7610 with a FEL and I would smell the same thing and it would drive me nuts cause I couldn't find any leaks, so I asked my dealer and he said this was normal that I was smelling fumes from the vent under the seat.

 

[Northland]

I have never noticed any smell from my B7800.

However it has "puffed" a few times from the FEL valve. I have a WR LONG valve kit attached for use with my bucket grapple and it really surprised me when it "puffed" what looked to be hydraulic fluid & air (like steam). No problems though.

 

[Stoweski]

Well, after using the tractor for several days I noticed the smell once again. I did some more searching and finally found a leak from the connector between the 'hydraulic tube' and the 'hydraulic hose'. This would be on the right arm of the FEL. Eventually it did get worse and started dripping occasionally on the right front tire. The connections were all tight so I unscrewed each connector and put teflon tape on the threads. This has solved the problem for me.

My question is regarding the teflon tape. Is this an appropriate solution for a hydraulic line? I have used it on my log splitter on the non-pressurized return lines but never on the pressurized lines. Being that this is my first tractor (even though I've had it for over 2 yrs) I would rather not mess something up and cause a bigger problem if teflon tape is not a viable option. If teflon tape is not appropriate is there an alternative?

Thanks for any input!
Keith

 

[Harry c]

When you move a cylinder on the FEL for instance, the rod side contains less fluid than does the piston side. When you extend a cylinder, the fluid level in the reservior actually drops a bit. The vent allows air into the reservior. When you retract the cylinder, the fluid level rises. The air that was vented into the tank is now vented out. The odor is just that air and the smell of the hyd fluid being repeatedly inhaled and exhaled from the vent. If you are working it hard or the weather is hot, the hyd fluid will give off more "vapors" and the smell will likely be stronger. If the wind is blowing, you probably won't smell it at all. The smell is normal on any vented sytem whether HST or gear. The HST will likely heat the oil more than the gear trans and may have a little more smell as the oil gets hotter.

As for teflon tape: Loctite makes a special product for hydraulic fittings. I think Kubota uses something similar for the original assembly. Teflon tape is ok if you are careful about how you use it. Don't let the tape lap over the end of the male fitting. If you have excess over the end, the strings can come loose and go through the system. It really shouldn't hurt anything because the suction screen will catch it but I'm always kinda careful about it anyway. Since the Teflon isn't abrasive it won't hurt the cylinders, etc.

 

[brandoro]

I think Harry c answered the question. I have noticed the hydraulic smell on my 7610 when using the FEL when there is little or no wind. The vent is just below the back of the seat. The changing volume of the cylinders as they extend and retract is what I have convinced myself causes this. I haven't noticed it when mowing but most likely my forward motion keeps me ahead of any venting of fumes that might occur. The vent has remained totally dry. After solving a couple of small leaks when the tractor was new I haven't seen any trace of leakage and no change in the level on the stick, taken sitting level on the shop floor. On the B7610 that means pull the stick, wait a minute, put the stick back in, pull out and read that level. After operating the tractor air gets into the dipstick tube, the O ring on the stick keeps the fluid from getting back in so first pull on the stick usually shows you a dry stick . First time that happened drove my heart rate up a bit. Took a little think time to figure that one out.
There are other threads that cover the teflon tape and the dry dipstick issue quite well if you want to do a search.