Steering box DIY rebuild

[Moseley]

Evening all,

I’ve just embarked on stripping my steering box as it isn’t in a particularly good way with the amount of play in it at the straight-ahead position. I’ve managed to get hold of an OG steering pin, so thought it’d be no harm to chuck this in, however, it seems someone has been in there before and fitted an aftermarket one-piece pin, so I’m not sure on what parts are missing.

Below are photos showing the OG pin loosely fitted in the arm which just is the two pin parts, and the washer. Next to it is the one-piece with a variety of washers and the locking tab.

I know I need the locking tab washer, but should there be any other spacers etc?



As an aside to this, I have found that the steering pin was not adjusted properly - it was far too tight and wasn’t rolling up and down the worm, so at least I know I can sort this. The worm looks ok to me, but then I’m not entirely sure on how ‘bad’ a bad worm would be visually. Will be looking for other sources of wear (and potentially look to have the case machined and bushed) when I do a dry assembly before it gets a lick of paint.

Stay tuned as this thread may turn more extensive…

 

[YellowBay69]

Evening all,

I’ve just embarked on stripping my steering box as it isn’t in a particularly good way with the amount of play in it at the straight-ahead position. I’ve managed to get hold of an OG steering pin, so thought it’d be no harm to chuck this in, however, it seems someone has been in there before and fitted an aftermarket one-piece pin, so I’m not sure on what parts are missing.

Below are photos showing the OG pin loosely fitted in the arm which just is the two pin parts, and the washer. Next to it is the one-piece with a variety of washers and the locking tab.

I know I need the locking tab washer, but should there be any other spacers etc?

View attachment 8133View attachment 8134

As an aside to this, I have found that the steering pin was not adjusted properly - it was far too tight and wasn’t rolling up and down the worm, so at least I know I can sort this. The worm looks ok to me, but then I’m not entirely sure on how ‘bad’ a bad worm would be visually. Will be looking for other sources of wear (and potentially look to have the case machined and bushed) when I do a dry assembly before it gets a lick of paint.

Stay tuned as this thread may turn more extensive…

Will keep watching as this is something I want to do with mine.
Good luck

 

[slowmo]

These are the parts from my steering box rebuild.
My steering pin was the one piece design but I brought a replacement NOS one which was two piece. I replaced all the rollers with new ones on the pin. I also replaced all the ball bearings on the worm gear.
A bad worm gear normally has damage/marks in the bottom of the valleys where the pin had worn such that it sits into the bottom of the worm. Also look for flat spots on the steering pin as they stop spinning and get damaged.

 

[Graham L]

Having rebuilt lots of boxes I've never seen a 2 piece peg as far as I'm aware the 2 piece design was from a split not a bay. looking at the output shaft it has a lot of wear in it which will be creating the play as it will move side to side in the steering box case, the bushes within the case have to be reemed out and new bushes fitted but no one makes those, also the blueing at the top by the peg shows the shaft has been getting hot, seen it a lot where boxes have been over adjusted to try and take the play out.

With regards to washers thats all there should be, the shaped washer that sits on top of the needle bearings, then the plain washer, tab washer and then the nut, not sure what the big washer at the bottom is, never seen that one before.

Wear on the worm shows up as gouges in the outer surface of the helical spiral (i'll try find a picture) if its really been over adjusted chunks come out of it and its case hardened.

 

[Moseley]

These are the parts from my steering box rebuild.
My steering pin was the one piece design but I brought a replacement NOS one which was two piece. I replaced all the rollers with new ones on the pin. I also replaced all the ball bearings on the worm gear.
A bad worm gear normally has damage/marks in the bottom of the valleys where the pin had worn such that it sits into the bottom of the worm. Also look for flat spots on the steering pin as they stop spinning and get damaged.

These are the parts from my steering box rebuild.
My steering pin was the one piece design but I brought a replacement NOS one which was two piece. I replaced all the rollers with new ones on the pin. I also replaced all the ball bearings on the worm gear.
A bad worm gear normally has damage/marks in the bottom of the valleys where the pin had worn such that it sits into the bottom of the worm. Also look for flat spots on the steering pin as they stop spinning and get damaged.

Cheers for the tips, I will pop up some photos in due course of progress so far. Everything is stripped and degreased, and as Graham has alluded to, it seems the 2-piece peg is indeed a split screen part, although they seem to be interchangeable. The only issue I have found is that it is an M10 thread whereas the bay window ones are M12. I can’t see anywhere that sells the locking washer in the smaller size, so I have ordered a couple of similar items and will see if they will be an ok substitute.

Having rebuilt lots of boxes I've never seen a 2 piece peg as far as I'm aware the 2 piece design was from a split not a bay. looking at the output shaft it has a lot of wear in it which will be creating the play as it will move side to side in the steering box case, the bushes within the case have to be reemed out and new bushes fitted but no one makes those, also the blueing at the top by the peg shows the shaft has been getting hot, seen it a lot where boxes have been over adjusted to try and take the play out.

With regards to washers thats all there should be, the shaped washer that sits on top of the needle bearings, then the plain washer, tab washer and then the nut, not sure what the big washer at the bottom is, never seen that one before.

Wear on the worm shows up as gouges in the outer surface of the helical spiral (i'll try find a picture) if its really been over adjusted chunks come out of it and its case hardened.

Thanks Graham for the pointers. The shaft is indeed showing a reasonable amount of wear now that I’ve been able to trial it back in the degreased case. Fortunately, a work colleague has a very good condition steering box from back in the days when he used to manufacture the internals, and he has kindly given me the pitman shaft from his which has removed a lot of slop and saved the need to bush the housing. My worm seems to be in ok condition, certainly dry-fitting the components and it feels a lot better than it was before I had stripped it down. The peg I removed is a bit suspect as it looks to have seen some action with a grinder, albeit I can’t detect any flat spot in it.

 

[Moseley]

Dodgy looking thread on the pitman shaft:



Comparison between OG split screen peg on the left (currently with no washers of any description) and the aftermarket one of unknown origin on the right with the selection of washers / bearing race stacked up as found. Note the peg end looks very short and the bottom appears to have been rounded off mechanically.

 

[matty74]

Great info in this thread, thanks to all for sharing

 

[sparkywig]

Try accu for hardware.

 

[Moseley]

Overdue update on this - been tied up with other projects so this has sat on my workbench awaiting some free time / camping deadline pressure! I'm creating this post as there are a number of useful resources on the subject that I referred to for the purpose of overhauling the steering box. Hopefully it will contain some nuggets of information that will be useful to others embarking on this:

2-piece peg locking washer and installation:

The locking washer does not seem to be available for the 2-piece peg, so I bought one of the washers in the link below which seems to work well as a replacement. I flattened the tangs in a vice before fitting, and then bent one to suit once installed. The tangs aren't as long as the 1-piece peg locking washers available, but it seems robust enough to stop the nut from loosening.

https://www.ebay.co.uk/itm/334330560342?itmmeta=01J1PYDVG3BMND89YPR7Y3MA31&hash=item4dd7a77f56:g:U3QAAOSwm8ViC3xA&itmprp=enc:AQAJAAAA4LW7yb8JIOW4yDFqDzj2fXi1xe812hqJHUcP5lE5NFKRMu72VsIbELcvclUAbbb07ygunt7Fx/u8Rqu71QqmHNnXyUXH/GEVgMa5rWznG8PsebnsJQZ4TTNC6c5kU952WZoO3q2dUioLDY/SHzY4KSui9WW5DyqtrKcpi7mCUzcv1yTUcRbeNqjxxbQ2qGisYEI2o+l7Jrh9PyBcZKne0eeWtxc9joEhmgI3v/Ucume7nEUCyO6yjdoT7AhrNKIxf2Z5DHo25MeSRXzsCZX+/TMZZDWvIvLqhfOpfpdMIo4o|tkp:Bk9SR5i4t96NZA

I would advise steering clear (excuse the pun...) of using this peg type - the top race needs some pressure to mate it with the peg, which is achievable if it can be pushed by hand far enough onto the peg to allow the nut to start to be threaded. This is where the fun starts - the nut is a snug fit, so the peg wants to rotate as it is tightened. It is an absolute pig to place all of this in a vice to allow the nut to be tightened, all whilst avoiding jogging any of the upper or lower bearing rollers from where they're lightly held in place by some grease. The 1-piece peg design is far less fiddly, and is presumably a design evolution from the Splitscreen steering boxes.

Sealing the box:

I used a thin coat of 'Stag Wellseal' for the mating faces, including all three worm preload shims, and the gasket for the case halves. For the shaft seals, the sizes are in the link below, and I opted for R23 variants (over the more-common R21) to add a second lip to help minimise the risk of dirt ingress / grease leakage.

Assembly grease:

Horrible black, bog standard molybdenum grease as typically found in CV joints. Only a small amount needed to hold bearing rollers to their races, and a thin smear on seals to assist in fitting.

Filling the box with lube:

Filling the steering box with Penrite started off as a bit of a pain. I heated the bottle up in a saucepan of boiling water (don't tell the other half...) and then attempted to decant it through a funnel. Needless to say, even when hot, this stuff doesn't flow enough to make it down the neck of a funnel! In the end, I found drilling a 5mm hole in the middle of the lid and using the bottle like a squeezy bottle worked well as I could jet the grease into the box whilst spinning it through it's travel to let the grease settle.

Useful links:

This is a great write-up with torque specs / details of how to preload bearings correctly: https://www.itinerant-air-cooled.com/viewtopic.php?t=11096

 

[matty74]

Brilliant write up, thanks for sharing