How much play is acceptable? Whitlock Mamba steering

[Kelpie]

We have Whitlock steering with rods and gearboxes, on a late 70s Moody.
I've noticed that there is some play on the system, possibly at the final gearbox before the linkage to the quadrant. Certainly it's enough that when the wheel is lashed amidships, the rudder can still move a bit and the grating of the autopilot ram is pretty annoying, especially when it's right underneath the berth.

a) other than the annoying noise, is this a big problem? Is it likely to get worse over time?
b) how do I go about fixing it? Is there a simple adjustment somewhere?

 

[Fr J Hackett]

There is a worm and gear in the head of the binnacle but I doubt that is worn next is the vertical drive shaft into the gear box that then transmits the wheel movement via a rod or rods with rose joints to the quadrant this is where the play is most likely and where I would check first. You can adjust the linkage quite easily by lengthening or shortening it by screwing or unscrewing the rose joint coupling on the rod linkage and then relocating it with the nut that is there, a bit like adjusting a tracked end.
Failing that search for Cliff Mogeridge who bought all the Whitlock stock from Lewmar and now runs a business around Whitlock steering and servicing.

 

[Fr J Hackett]

Correction it is two bevel gears in the top of the binnacal I was thinking of something else.

 

[penfold]

As the priest says the spherical joints onto the tiller are good candidates for wear and replacement, also inspect any universal/hookes joints in the drive shafts as they are a weak point too. In my limited experience with these the gearboxes are generally very over-engineered and do not wear appreciably in the life of a boat.