Leaking steering knuckle, how to fix?

[Lars S]

Discovered that grease exits the steering knuckle at the bottom seal for the pitman shaft. The seal seems to be changeable from outside but how do I refill the knuckle...don't want to touch the adjust bolts on it...no other openings available?


/Lars S

[raygreenwood]

There are several issues with this. The seal is a unique size. It is not hard to find one with teh correct thickness and ID...but hard to find one with the correct OD. I used a smaller OD seal and epoxied it in.
I can also have them made (as I found after the fact)...if anyone is into a group buy.

You need to remove the gearbox and look on top. You will see several small plastic plugs up in the top side if memory serves. I can look at a spare when I get home.

What I did is remove the seal, remove the top bolts and the lock nut from te htop adjustment. That part of the adjustment is easy...so don't be afraid of it.
You need to then tip/slide the lid sideways so you can see inside. You are NOT removing the lid...as that would mean taking teh knuckle and balls out.
Dunk the whole unit is a pretty hot solvent like carburettor cleaner. Wash out all the oil...keep doing this until it runs clean.

The grease in this gearbox..is not grease or an oil. It is technically a thickened gear oil....much like a Browning Power-take-off unit oil.

What I use...and it works superbly in all weather....is a non-toxic, very creamy food grade clear grease. It does not tack up. You spoon in as much as youcan. Run the gearbox side to side to get the grease into teh bearings. pack in even more. Then put the lid on...install a grease fitting in one hole...and then force feed grease into the box.
The object is to get the box full with no real air spaces at all. That way every turn of the box pumps grease through the bearings every time you turn the wheel. Plus...its not a liquid...so it will never leak past the seal..even if you re-use your old seal.

This is the product: http://www.super-lube.com/synthetic-mul ... -ez-49.htm
It is used in a vast array of products and machinery on this contient. It is clear, non-toxic (food grade) is approximately the consistency of "warmed" vaseline and good from -40-450F. Ray

[Lars S]

Thanks again Ray! The super-lube seems to be available also over here.

/Lars S

[herr_sparky]

what luck...i was just about to post the same question.

my steering box long ago leaked out all its lube and i have no spare. i did find 2 small (1/2") size plugs on top that look like ports for a grease gun, but to get at them the 'box must be removed...

[raygreenwood]

Yes..box must be removed. Do NOT pull off the pitman arm. It is easier to simply remove the center tie-rod link.....and....if you have not replaced or rebuilt the centerlink yet...it needs it on almost every vehicle.

So the easiest way to proceed...is to use a "pickle" fork and pop out the center tie-rod from the pitman arm. Then pull the boot back so you can see the steering shaft to steering box joint. It is easiest to mark the position of steering wheel shaft to the cast fork that is splined onto the steering box shaft and held by a pinch bolt. Mark it with a permanent marker or paint on the cast iron fork....then on the shaft of the steering box. Then when the box comes out...mark it with a punch mark permanently as the marker will be washed off of the stub shaft coming from the box when you drop this in solvent.
In this way...you do not have to get under the dash and worry about grounding and horn connections.
Next...remove the left hand wheel and the three plastic plugs in the fender well. Put something soft on the floor under the steering box (wood will do) Remove the 3 17mm bolts. The steering box will fall on the floor.

This grease is excellent in teh box. I did mine like this in 1995...and it still has the old seal which originally leaked all of the oil out (I could not find another at that time)....but the synthetic grease is thick enough it does not leak out at all. Initially it pushed about 10 grams out because the box is fully packed....but after that...nothing. Ray

[herr_sparky]

for what its worth, this type of grease is identical to the kind used in modern 10spd. index shifting systems (on bicycles) that require zero tack and no gumming-up over time... an old boss of mine actually misunderstood the "food grade" designation as "edible"...

[raygreenwood]

Oh...it wouldn't kill you....but it certainly will make things interesting in the mens room for a few days.

The nice thin gabout this grease is that when working with it, if I get it on my hands...my hands don't break out like other metal based greases do.
Though it has an excellent drop point, I have not enough info yet on its extreme presure/Timkin load properties to put it into a disc brake bearing yet.
In very cold winter locations.....Northern Eurpoe perhaps....I woudl highly recommend using it for wheel bearing. It stays very soft in freezing weather and would afford better lubrication of bearings in cold environments. In very hot environments....not sure yet. I use this grease for a great many precision things...including lubing the mazda bearings in my struts and the idler arm bushings and other areas. Ray

[wildthings]

When out on the road the sector shaft seal on one of my bays started to really pour its oil out. Not wanting to be down for a repair far away from home, I drilled a small hole near the top of the box and used a needle to force some grease into the box. I just used moly because that is what I had, but a synthetic like Super Lube would be better for the long run.

For my T4 I was able to find the correct seals from a local bearing house. I just gave them the sizes and they were able to find two sets of seals for me. No question they were old stock, but so far so good.

[raygreenwood]

Very cool wildthings. Yes, its been a few years since I actually checked for seals. When I rebuilt the one that is one my car right now, I went through dozens of bearing companies and it was just a pretty non-standard OD of metric seal. Not that it had never been made...just that its not common. That was 10 years ago.

Also....I could have gotten a seal that was perfect in thickness and OD...but 1-2mm too small in ID. I was too worried at that point to try a tight seal. Knowing what I know now...I would not be worried at all....especially when using a very fluid grease instead of an actual oil.

The problems with "most" greases...is that they thicken up with anything other than the wrarmest weather and get pumped out of the way of the recirculating ball bearings in this gearbox. This is why most manufacturers use an oil.....but its not just average gear oil in the type 4 box. It really similar to some of the browning type gear oils. Very thick and viscous like some of the lubriplate products from years ago. They are sulphur based I beleive.

I just happened to luck upon that particular grease at the time I needed it. It flows well.
But...its still a grease. So...the trick to making it work in this gear box is to fully fill the box...with almost no air space left.

Once you look inside of the box...you will understand. Turning the wheel adds no volume. All of the parts are already inside.
If you fully fill the box...and grease is filled into all areas....as you turn the steering wheel and knuckle moves along the threaded rod inside....it moves through the grease...pumping it through the knuckle and ball bearings. you may get a little grease pushing past the seal on the first hot day as the grease expands. Once you get the excess out...it will never leak again. These gear boxes with grease in them...if the bearings are good and the adjustment is adequate...will last virtually forever. Ray