Bolo
Sustaining Member
Anyone with a Raymarine ST400 MK2 wheel drive will eventually hear this:
That annoying squeaking sound usually means that there is a worn out internal drive belt or more often too much tension on the belt which can addressed by adjusting the clutch with the knob located near the drive motor. Or, if the squeak is slight and infrequent a little water poured down the hole at the top of the drive can help.

NEVER, EVER, use a mineral based solvent (such as WD-40) to lube or clean the wheel drive. (See the owners manual, page 31)
But in my case no amount of clutch adjustment or water solved the squeaking which just got louder the more I tried to adjust the clutch. So, my thinking was, the belt needed replacing. When I took the wheel drive off and opened it, to replace the belt, I was surprised to see that one of the plastic studs, which has a metal threaded insert, was broken off. This probably was my real problem.

I first drill a hole through the wheel drive ring, at the center of the broken stud, so that I could run a new longer screw though the threaded insert, matching it’s threads, and out the other side where I added a flat washer and locking nut. This held the broken stud firmly up against the inside wall of the wheel drive after I used some J-B weld epoxy to glue it back in place.

The new screw and nut didn’t interfere with the workings of the wheel drive so I left them after the epoxy cured. The little bit that protruded out the locking nut I cut off later. (Not shown in the photo)

I reassembled the wheel drive back on the binnacle and all that’s left is to test it out which I’m sure will work out. (Famous last words, right?) But this quick, easy and low cost fix for the broken plastic mounting stud saved me the cost and hassle of finding a replacement ring or possibly having to buy a whole new wheel drive.
That annoying squeaking sound usually means that there is a worn out internal drive belt or more often too much tension on the belt which can addressed by adjusting the clutch with the knob located near the drive motor. Or, if the squeak is slight and infrequent a little water poured down the hole at the top of the drive can help.

NEVER, EVER, use a mineral based solvent (such as WD-40) to lube or clean the wheel drive. (See the owners manual, page 31)
But in my case no amount of clutch adjustment or water solved the squeaking which just got louder the more I tried to adjust the clutch. So, my thinking was, the belt needed replacing. When I took the wheel drive off and opened it, to replace the belt, I was surprised to see that one of the plastic studs, which has a metal threaded insert, was broken off. This probably was my real problem.

I first drill a hole through the wheel drive ring, at the center of the broken stud, so that I could run a new longer screw though the threaded insert, matching it’s threads, and out the other side where I added a flat washer and locking nut. This held the broken stud firmly up against the inside wall of the wheel drive after I used some J-B weld epoxy to glue it back in place.

The new screw and nut didn’t interfere with the workings of the wheel drive so I left them after the epoxy cured. The little bit that protruded out the locking nut I cut off later. (Not shown in the photo)

I reassembled the wheel drive back on the binnacle and all that’s left is to test it out which I’m sure will work out. (Famous last words, right?) But this quick, easy and low cost fix for the broken plastic mounting stud saved me the cost and hassle of finding a replacement ring or possibly having to buy a whole new wheel drive.