C line steering box Qs

The steering box on my C1800 is leaking, there's heaps of oil around it (not that makes it stand out on the truck...). I assumed it was the shaft seal so bought a new one. Now when I go to put it in and have a closer look I reckon it's coming from higher up. Really it looks like its coming from where the steering column comes in.

I've searched the C line parts manual and D line service manual and can't see mention of a seal. How is oil kept in with a straight through (no unis) steering column? And has anyone else had this leaking from anywhere but the shaft seal? It's an S25 I reckon.

The D line service manual has good detail on the AB180 column, which has a seal at the bottom of the column, but it also has unis. The C line parts has my colum but no seal and split in two drawings (top for the colum around the steering wheel, bottom for box). The D line SM has a couple of other columns but both with unis none like my CD1820. Surely the D1830s were the same?

Also I can't find drain plug, how do you get the oil out?

Does it have a brass bush?

No, no brass bush. According to the manual the tube goes into the upper housing (which clamps it), then it is shimmed off the main housing. Next is a bearing and I guess it could be a sealed one but I reckon that's unlikely. It sort of looks like the oil is coming from between the shaft and upper housing...

So does anyone know the drain procedure on these?

Just did box on D1310, looks similar design, NO seal on top, only way to drain is take side plate off. Could it have been overfilled?

Just did box on D1310, looks similar design, NO seal on top, only way to drain is take side plate off. Could it have been overfilled?

yeah does look the same. Are there any complications removing the side plate? I see the adjuster screw is set in it, nothing comes with it or falls out? Also I'm guessing if you can't reuse the gasket you have to reset the screw...

Not overfull as I couldn't see oil at the filler.

Maybe the oil is coming from elsewhere then, I'll have to give it a good clean and top up with thin oil for leak finding

Is it spiting out of the oil pump?

Is it spiting out of the oil pump?

what oil pump? No PS...

Hi Wedgetail,

I also have not long done the steering box on our AB120. Other than the size the mechanism is the same.

They are a pretty simple build,

Agree with spinnerboy, the only way to drain them is to take the side plate off. No issues with this and nothing will fall out. I would just crack the lock nut and back off the adjustment screw before you take it off and so you can re-do the adjustment after assembly.

The sector shaft, that is the steering output shaft rotates on brass bushes and where it connectes to the drag link there will be a seal.

On the worm shaft, the steering column, there is no seal. So there is potential to overfill the steering box and have a leak. If the oil level has been down then you might find some wear/damage to the top worm shaft ball bearing. The worm shaft has cup and cone caged ball bearings like a push bike. The upper housing has the shims to provide pre-load on the worm shaft bearings.

On the lubricant side the manual for mine asked for "self levelling grease", essentially it is grease you can pour. Penrite make this grease and it is sold as "Steering gear grease". In my case I managed to find a recipe from Castrol back in the day and the blend was 50% 140W gear oil and 50% Moly grease. This has worked well and my steering box is like new. I did leave the steering box and prepared Grease/oil blens in the sun before filling it up.

Does your C1800 have a brake/clutch master cylinder on the fire wall above the steering column? If so, could the leak be brake fluid running down the steering column?

Hope this helps.

Regards
Roger

Thanks Roger, I was putting straight 140w90 in it so maybe that's why it was coming out. It's definitely gear oil leaking, was doing it since before I got it. I guess it could be coming out the seal, I'm just not sure how it could migrate up the column to that first joint. There's none above the joint though so it's not coming from above.

Thanks for the tip on the brew, I'll nock some up and give her a change.

Just a note on the oil on the spring.

The spring relies on friction between the leafs to help the shocker dampening. With all the oil in between the spring leafs, the shocker will be working overtime.