How much grease to pump into a zerk?

davrow · May 14, 2014

Which grease and grease gun has been talked about a great deal. But I couldn't find a good thread (any thread, actually) on how one knows when you have put in enough grease.

With some joints it is easy, pump until old grease comes out. But that isn't universal, stuff with seals I understand you can blow out the seal by putting in too much.

How does a newb (me) know when they have pushed in enough, but not too much? (and, does it depend on which fitting you are greasing?)

Thanks.

(so far I've counted 25 zerks on the loader and front axle. Lost track when counting on the backhoe!)

k0ua · May 14, 2014

The ones on the front axle just put in 2 to 3 pumps every 50 hours. You will of course not see anything. Just learn what the "feel" of a zerk taking grease feels like. The loader will need greasing every 10 operating hours, as you said pump until you see grease movement. Some of the lower ones that can easily be 5 or 6 pumps. I don't know about the backhoe, I have never had one, but I would assume just like the loader. As for the under chassis ones, a couple of pumps every 50 hours.

texasjohn · May 15, 2014

kOua covered all the key points EXCEPT one. On your tractor there are at two zerks you haven't found...and these are the most important ones!! You mean you don't know where they are??? There, see what I mean??

Seriously, every tractor I've ever had has hidden a couple of zerks from me for a long time....to be discovered when least expected.

The most important one is in the middle of the front axle, under the tractor, where the axle pivots up and down. On my tractor, the fun thing about this zerk is that you take a plug out, add grease to the zerk until it begins to come out of the plug hole, then insert plug again. This is done while laying on your back.

So, which two zerks do you not know about??

jagyzf · May 15, 2014

Follow your manuals instructions, that is the best source for what to grease and when.

In general as others have already stated

Pins and bushings with no seals like loader pins you can pump as much as you want. U-joints and others with seals, too little IMO is better than too much.

A good friend of mine bought a used disk mower. Some of the drive line U-joints had been replaced, others not when he bought it (they ran it through their shop and replaced anything in question). He greased it every time he used it. 1/2 way through the season he had to replace all the U-joints on his drive line. Manual calls for I think 20 hours on some 50 hours on others. He was around 2-4 hours at each greasing. Needless to say as he told me, he learned a very expensive lesson. That was 10-12 years ago, he still has the same mower and hasn't replaced a joint I know of.

jonnyc1999 · May 15, 2014

How would putting in fresh grease be detrimental? I thought the point of it was to push fresh lubrication in, and contaminates like dirt, water and debris out? Other than putting a bigger dent in your wallet? It sounds more to me that there was a problem with the u-joints of your friends disk rather than the greasing. But I'm just a regular guy, so I'm just applying "more is better" sense to the situation

torrin · May 15, 2014

Too much grease will damage oil and grease seals, and that will allow dirt in and grease out.

Looking4new · May 15, 2014

There are two grease fittings on your brake rockshafts (both sides of the transmission housing) that are impossible to get at with a straight gun fitting. You need to either replace them with right angle fittings (good luck with that, there are so many different sizes and threads) or get yourself a right angle grease gun coupler. Any good automotive parts supplier should have these or can order one for you.

jagyzf · May 15, 2014

jonnyc1999 said:
How would putting in fresh grease be detrimental? I thought the point of it was to push fresh lubrication in, and contaminates like dirt, water and debris out? Other than putting a bigger dent in your wallet? It sounds more to me that there was a problem with the u-joints of your friends disk rather than the greasing. But I'm just a regular guy, so I'm just applying "more is better" sense to the situation

What he said

torrin said:
Too much grease will damage oil and grease seals, and that will allow dirt in and grease out.

If the parts have seals, the seals keep dirt and moisture out, by over greasing you will blow these seals out. My friend didn't think he was doing any harm either, even though I had explained to him he was. He even asked a few mechanics at dealer ships about it and they all told him the same thing. Too much is not a good thing with sealed items.

Also bearings and gears can be over greased. Over greasing causes heat to build up and break down the grease. Which really does apply to U-joints from the stand point that they have bearings in them.

These are 2 I found quickly on bearings, lot more if you look. As I said, too much IMO is far worse in some cases than too little.

Bearing Failure Due to Over Lubrication | Bel-Ray Company, Inc

The Dangers of Overgreasing

There may have been a time when over greasing was OK, but with todays stuff the seals are very good. I know when I had a U-joint put in my last truck the mechanic also said to only put 1 shot if any at all at 40-50K. The U-joint lasted over 100K past that time before I traded last fall and I only greased it once.

davrow · May 16, 2014

Thanks everybody, you have pretty much confirmed what I thought.

Mostly I want to grease the loader and backhoe pins often, and I'm comfortable with those. It's all those hidden ones underneath that I don't even know what is being greased that get me.

The manual is good about saying what to grease, and when. But not once does it say 'how much' (that I have found).

texasjohn said:
The most important one is in the middle of the front axle, under the tractor, where the axle pivots up and down.

That one is interesting. It is why the count of zerks comes out as an odd number. Every other zerk on the loader and front end has a corresponding right and left. Except that one.