lt40 hydraulic problem

wolf nemeth · May 08, 2015, 08:24:54 PM

Well, just when I thought I'd finally experienced every common problem known to WM owners, I have another one.......
Everything wash going smoothly until just before quitting time yesterday. then the hydraulic levers felt strange---it didn't matter which lever, it felt like something was hitting or grinding in the system.
So I took off the cover, suspecting low fluid level, and unscrewed the cap.Then, when I lowered the last load back down to ground level, ye olde hydraulic fluid bubbled out like Texas crude. About a half quart gushed out..
About 100 hours ago, when I got the mill, I changed the fluid and filter and everything seemed all right. Now I'm afraid to run it. Anybody had a similar problem or want to venture some advice?

POSTON WIDEHEAD · May 08, 2015, 08:35:27 PM

If you move the hydraulics with the cap off, it will gush out. the pump is filling back up.
You may have been low on fluid, refill to amount needed and see if it works / sounds any better.

beenthere · May 08, 2015, 08:58:51 PM

Or look for air coming in through a suction line and causing the oil to foam... and expand... and have slow movement.

MartyParsons · May 08, 2015, 09:44:13 PM

Hello,
If you have a LT40 Super with two pumps one pump is not working. Need more information. How many hours?
Marty

wolf nemeth · May 09, 2015, 09:10:59 AM

It's an lt40HD with about 3600 hours, year 2000. One pump.
In terms of possibly being low on fluid, how is that possible when the tank overflowed with all the hydraulics set to 'zero'? I'm not arguing, just confuddled...... and the original situation was feeling some bumps when I used any hydraulic lever.
Air in the line sounds like a possibility, but the fluid gushing out was not foamy. Well, I'm headed back out there today with some Dexron and will report back. thanks for the input!

MartyParsons · May 09, 2015, 10:48:00 AM

The oil level should be 1/2 in from the top of the res. with all cylinders closes. If you fill it up and the cylinders are extended you will push some of the oil out.
M

Ga Mtn Man · May 09, 2015, 01:49:37 PM

Hmmm...that might explain why the inside of my hydro box is covered with fluid :

.

Ohio_Bill · May 10, 2015, 08:02:28 AM

Good morning, like others have said, with the cap off oil will come out. The noise you are hearing i would suspect is from the pump motor, brushes or just worn out .

Chuck White · May 10, 2015, 11:44:06 AM

Not to side-track this thread, but......

Question for Marty. My mill is a 1995 and my book says to maintain a fluid level of 4½" of Hyd Fluid in the reservoir with all cylinders collapsed.

You mention a level within ½" of the top, is that for newer mills, or is it a recommended change for all hydraulic mills?

Thanks.

wolf nemeth · May 10, 2015, 09:06:19 PM

Well, I got back to the mill and collapsed all the hydraulics; my fluid level was just about half a tankfull. so I added several ounces, started thing up, and sawed a couple of logs. No problems, not even the knocking feeling in the valve handles.
Since I live by the adage 'don't fix it if it ain't broken' I guess I will just wait until the really obvious problem develops.
Thanks for all the input I love this forum!
Wolf

terrifictimbersllc · May 12, 2015, 04:08:31 AM

Quote from: Chuck White on May 10, 2015, 11:44:06 AM
Not to side-track this thread, but......

Question for Marty. My mill is a 1995 and my book says to maintain a fluid level of 4½" of Hyd Fluid in the reservoir with all cylinders collapsed.

You mention a level within ½" of the top, is that for newer mills, or is it a recommended change for all hydraulic mills?

Thanks.

Chuck, might that not be about the same thing, 4-1/2 from the bottom = 1/2" from the top? My book says 3/4 from the top.

Chuck White · May 12, 2015, 07:55:35 AM

I couldn't really tell you without going out and checking.

I use a wire dipstick that I've been using since I've had the mill and I maintain 4½ of hyd fluid.

I don't think it's within ½-¾" of the top though!

MartyParsons · May 12, 2015, 11:26:50 PM

Hello,
I think you will find there is some variables to the level. It does not need to be exactly on the mark. There needs to enough oil in the res. so the pump does suck air and not to much when you cycle the cylinders the the oil does not purge out or blow the air breather ( green sponge) off. Early mills have a screw later pumps have a black cap with the green sponge. I get a chance I will read the exact paragraph in the book and post.
The later (newer) pumps you can look in the vent hole and see if the pump is covered in hyd oil. There are two holes on top of the res. one is the vent and fill hole the other is for other applications for oil return.
Hope this helps!
Marty

Chuck White · May 13, 2015, 07:47:12 AM

Thanks for the response, Marty!

prittgers · May 14, 2015, 01:52:10 AM

When we do WM training here in Alaska, we mention that those filters are less than $15.00. Those pumps, on the other hand, tend to cost a bit more.

In the winter if you're not using your mill, put the lift arms up in the parked position so that as moisture condenses, it doesn't settle down in the bottom of the cylinders. One of our customers has replaced the little safety fuses 2x because of ice forming and breaking them.

Hydraulics are really nice to have aren't they!