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MG MGB Technical - Missing Grease Zerk on Kingpin?

While greasing the front suspension on a "new-to-me" 74.5 "B", I found all three grease fittings on the passengers side but the middle fitting on the drivers side is not there. I have cleaned down to the metal and the top an bottom fittings are obvious but there is no middle fitting, ie. the upper fitting on the bottom of the Kingpin. Were some made this way? do both lower Kingpin fittings lubricat the same spot?
Tom Gillett

Sounds like an unusual error in manufacture - but Im no expert. I think there should be three per side.
J Delk

Hi:

I seem to remember that only the very early MGB's had 2 fittings. There was a modification notice years ago for updating to 3 fittings. If want the 3rd fitting you need to drill and tap the axle stub.

Good luck: Rich Boris 67 B roadster
Rich Boris

The fitting is around the other side of the upright, opposite to the one you found. That's where they drilled it when the factory decided that the third fitting was needed, after the first couple thousand cars were built - detailed in the shop manual.

Yes, the two bottom fittings grease the same TWO points, via different routes. This is a poor fix to a design error, that works very slightly better than it did at first.

The cure for this, which should be done on all cars, is to block the passage in the kingpin so that the lower fitting greases the bottom link/A arm bush, and the "added" fitting greases the lower swivel pin bush.

FRM
FR Millmore

When I do mine I find the middle one results in grease coming out of the top of the Kingpin. The other 2 the grease emerges from the bottom of the king pin and the swivel pin respectivley. I use a pro grease gun I eventually bought after a succesion of useless hobby ones, and the car needs to be on a lift to get on all the nipples and still be able to pump the gun(it's a side lever about 18" long). I'm using a moly grease now and so far so good.
Stan Best

The bottom fitting as original fed the lower arm bush and the lower swivel bush, through a branched drilling. If either passage gets blocked, usually by stiffened grease from poor maintenance, then ALL the grease goes to the other branch, leading to failure of the starved bush.

The "middle" fitting was added to ensure that grease got to the lower swivel bush directly. That's good, but if the passage to the lower arm bush is clogged, both fittings grease the swivel bush.

The top fitting greases the top swivel bush direct.

All three fittings communicate through the swivel pin dust tube after the grease goes through the designated bush, so grease can come out anywhere from any fitting, but the lower arm bush may never get any grease - It is very common to find the bushes worn clear though into the swivel pin eye.

FRM
FR Millmore

I crawled under my 79 MGB today and I greased it for the first time since I owned it. I have driven about 6k miles in the 6 years I've owned it. I did find the front end to be quite hungry. After I finished the job, I drove the car for a good 25 mile run over winding roads and noticed the car steered much "lighter" I am thinking perhaps I should regrease the front end now that the grease is "worked in"

Any thoughts

Also, are there any more grease fittings under the car which need lubrication??

cheers

Gary :>{D
79 mgb
gnhansen

Gary-
Shame on you! Should grease it at least once a year - this is what causes the grease to stiffen up and block the lower bush passage. Grease is just oil in a soap to keep it from running away, but after a while the oil drains out.
There may or may not be fittings on the u joints, and there is one on the driveshaft sliding spline - important. Late cars don't have fittings on the handbrake cable, early ones do.
Grease her up and git a move on!

FRM
FR Millmore

My 76 has a grease fitting on the handbrake cable, so at least check for it before you move on. It's toward the back of the car, and quite noticable.
...

I grease and change oil/filter at the beginning of the driving season (the moment the salt has washed off the roads) and thereafter every three thousand miles. While some U-joints do not have provisiion for zerks, of the ones that do, very often if they're short enough so has not to foul on the yoke, they cannot be reached with most grease guns. It's a pain in the butt, but I keep an Allen-head screw in the hole except when I grease it. Then I take the screw out, and thread the zerk on, with a short extension - long enough to get to it with a greaase gun, but too long to leave in place while the driveshaft is turning, so back goes in the Allen-headed screw.

I always carry spare u-joints. While you're at it, every three-thousand miles, check your shocks and replenish with shock oil as needed; check/top-up brake fluid in brake and clutch master cyllinders and if one takes any more than perhaps a teaspoon, check the entire system for leaks; put a drop of oil on the exposed screw head when you remove the rotor from the distributor spindle; check the dashpots on your carbs; and check/top-up the transmission and rear axle.

Also - do anything I've forgotten. 8^)

Allen
Allen Bachelder

Allen-
The can't grease it u-j is because it either has the wrong u-j, or it's installed incorrectly. The U-J fitting should be at an angle to the plane of the spider - some replacements aren't; and, there is a cutaway in the shaft that allows the gun to fit. It's in one position only, so you have to fit the spider correctly with the nipple toward the shaft center.
FRM
FR Millmore

Fletcher,

I suspect this is a case of mea culpa. I usually replace my own U-Js and I was not aware that there were wrong ways to do it. Not an immediate issue because my current daily driver has one U-J with a fitting that I can reach (I'm reminded of the million monkeys at a million typewriters), and one U-J without a fitting.

Thanks,
Allen
Allen Bachelder

Allen, don't feel bad. I got to install both U-Joints on the propeller shaft on the TD twice because I neglected to determine if the zerk fittings would clear when assembled. Then, I took it to a clutch and u-joint shop to balance it. When I dropped it off, the u-joints were quite stiff. When I picked it up, they ware all run in, very nicely I might ad.

Of course, I DID make sure the yokes were in the same plane on upon reinstalling on the car.

warmly,
dave
Dave Braun

After a nights sleep and your help I found the "missing" zerk.

Now I am curious, becasue I don't know the greasing history of this car, what can I do to clean out the old grease, if there is any, short of tearing down the front end? Do I just pump lots of grease in and hope for the best? From FR Millmore's comments, I think that blocking the passage would require a teardown but I am not sure.
Tom Gillett

OK, the sliding spline is located at the tail of the transmission, I suspect?? Am I correct in my suspicions?? So I will need to raise the rear of the car off the ground to rotate the d-shaft until I am able to locate and hopefully fit my pistol-grip style grease gun on the fitting and pump away.

I will re-grease the front of the car again now that I have driven it and "worked-in" the grease. My thought process is, the newly applied grease has had a chance to work its way around the king pins and upper and lower bushes, thus creating more space for addional grease.

FRM: the grease being in soap form is a good analogy. It makes sense and I never thought if it in that light - thanx

cheers

Gary :>{D
79 mgb
gnhansen

Gary -
The soap thing is not an analogy, it's what grease actually is; the soap base varies, hence "lithium grease", "sodium grease" etc.

And yes on the sliding spline - don't try to fill it, a few pumps is all it needs, excess will come out and go all over.

Dave -
The new U-joints were tight because the cups were not hard against the circlips. Be sure the circlip grooves are clean, and after putting the joint together, smack it with a hammer at each cup, just like you do to get it apart.

Allen -
You seem to have a lot o' them there "culpas" around those parts!

Tom -
Clean the old grease out by removing the fittings and going in with the appropriate drill bit, hand held - NO drill motor!

Draw yourself a picture to follow the following:

The vertical passage above the bottom fitting is about 2.125-2.250 deep. At about 2", there is the cross drilling to the lower swivel pin bush; at about .625 is the cross drilling to the lower fulcrum bush.
You want to block the passage between the two drillings, or more correctly, ABOVE the lower one. The passage is about .205 diameter, though it varies on different pins. Almost anything will block it, as you can tell by the fact that dried out grease blocks it. On new pins, I drip solder down the hole and then smack it with a punch to be sure it is tight. Some size of big nail is very close, cut a short piece and drive it in, or a piece of wood dowel with some glue on it - let the glue get set before you drive it in. Once the plug is in it won't go anywhere, as long as it can't fall out of its own weight. Just DO NOT block the lower cross drilling.
When you are done, the lower fitting will grease the lower fulcrum, the middle fitting will grease the lower pin bush, and the upper will do the upper pin bush. And any remaining dried out grease will be forced out by hydraulic pressure, since the grease now only has one place to go from each fitting.

I strongly recommend that this be done to all cars - if greased regularly, this almost totally eliminates wear in the lower bushes. Failures are a result of water getting in and rusting the parts, since there is no grease to seal it. That's why I'se broke - I keep fixing things too well!

FRM
FR Millmore

brilliant info! Was always reticent about asking this question, cause I couldnt quite believe the set up myself. I too have a 73BGT which has 3 nipples on the drivers side, but only two on the passenger side. Wondered what the score with this was for some time, particularly after cleaning it all up in the hope i would find the third - but never thought to look round the ohter side - simple, but not simple enough for simple folk like me obviously! Now want the day to be over at work so I can go find my missing nipple and get the grease gun out.
never fails to educate me, a quick visit in here. Mick
m rae

This thread was discussed between 20/05/2007 and 24/05/2007

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