After about 500 miles (and too many years) I changed the break in engine oil. There was some metallic grit on the drain plug magnet but none on the oil filter medium. Compression in all cylinders was 160 +/- 2 psi.

WIth the coach front end jacked up and the wheels off for mechanical inspection I decided to lube the front end. On the driver side lower ball joint it was necessary to firmly hold the grease nozzle onto the zerk fitting or grease would squirt out from the side of the nozzle. The passenger side lower ball joint was completely blocked and could not be greased at all. I removed the zerk fitting and it checked out OK. Then I removed the base to the zerk fitting and inside the ball joint could see a circular impression where the base fitting had bottomed out in the grease channel. Using a diamond blade on a dremel tool I cut notches in the base threads. That solved the problem and I can now easily lube the lower ball joints. These Moog ball joints were installed new a few years back. If I had inspected more carefully the first lube job the blobs of grease around the zerk fittings would have been obvious. Fortunately the ball joints don't have too many miles.

JP

I ran into that a few years ago with ball joints and posted my findings.

http://www.gmcmhphotos.com/photos/ball-joint-compare/p39635-dsc02815.html

I got no experience with leaving break in oil to many years. I did use Joe Gibbs break in oil and ran it about 1500 miles before changing with no evident issues.


Jp Benson wrote on Fri, 21 June 2019 19:29

After about 500 miles (and too many years) I changed the break in engine oil. There was some metallic grit on the drain plug magnet but none on the oil filter medium. Compression in all cylinders was 160 +/- 2 psi.

WIth the coach front end jacked up and the wheels off for mechanical inspection I decided to lube the front end. On the driver side lower ball joint it was necessary to firmly hold the grease nozzle onto the zerk fitting or grease would squirt out from the side of the nozzle. The passenger side lower ball joint was completely blocked and could not be greased at all. I removed the zerk fitting and it checked out OK. Then I removed the base to the zerk fitting and inside the ball joint could see a circular impression where the base fitting had bottomed out in the grease channel. Using a diamond blade on a dremel tool I cut notches in the base threads. That solved the problem and I can now easily lube the lower ball joints. These Moog ball joints were installed new a few years back. If I had inspected more carefully the first lube job the blobs of grease around the zerk fittings would have been obvious. Fortunately the ball joints don't have too many miles.

JP

Chuck Boyd wrote:
Sir: by cutting slots in the bottom of the zert it will allow grease to get in the ball joint but the end of the zert is still jammed against the joint and could cause wear or issues. I might advise shortening the overall threads to keep it from touching the ball. On my issue the housing was thin.

Jp Benson wrote:
Thanks for the link to the pics. Your last pic described the ball joint as bad so I presume that you solved the problem by replacing the ball joint.

I am concerned that the zerk is pressed against the rotating ball but don't know exactly how the ball joint is constructed internally. The clue that I noticed was a circular impression inside the ball joint that matched the end of the zerk fitting. As the impression was circular (rather than a scratch mark) I concluded that the contact point did not rotate but was a fixed channel of some kind. So I cut notches rather than shorten the threads. I'll take another look at that issue. The only cutaway ball joint pic I could find was a sealed model with a plastic internal cup. It was no help.

BTW the break in oil was dark colored which I guess comes from leaving it in too long.

Jp, I know how it is constructed and how it is supposed to work. (I had to, it was my job,) I had the same issue years back. The zerk fitting should not be interfering with the ball. If it is, the wear can shed metal into the loaded area. The fact that you can see wear means that it has already. The fact that the fitting did interfere with the ball means the part was tapped too deep by Moog.

A better short term fix would be (I know you really a want to crawl under there again) to use a cut off wheel on a (generic) Dremel tool to remove a thread from the fitting. When you get that done, pump grease through the fitting before screwing it back in. Mark that ball joint for replacement at some future date. The fact that it wore that far means it is well worn. Fortunately, the coach weight sits on the ball, so separation is not a big risk.

Matt

Jp, I know how it is constructed and how it is supposed to work. (I had to, it was my job,) I had the same issue years back. The zerk fitting should not be interfering with the ball. If it is, the wear can shed metal into the loaded area. The fact that you can see wear means that it has already. The fact that the fitting did interfere with the ball means the part was tapped too deep by Moog.

Matt

Richard
The zirc fittings come in many sizes of thread size.
Pipe thread, metric thread, sae thread and others.

I am sure that you can easily drill and tap the hole for a slightly larger thread size to solve your problem.

Emery Stora