Fixing the Autohelm

Since we have owned the boat, the autohelm has given us a few headaches. Not because of any deficiency in the autohelm itself, but more to do with the installation of it.

The first issue we had with it was in 2013. The hydraulic pump failed when we were on route to Brittany. The positioning of the pump meant that stray salt water that got into the lazarette corroded the pump and eventually it took its toll. A new pump, shipped out to Benodet fixed the issue.

The ends of the hydraulic pipes connecting the pump to the ram are mild steel, and that again does not mix well with salt water, so after several years of soaking in salt water, as we tested the new pump and deliberately loaded up the system to check for leaks, we blew a pipe! Luckily we found a hydraulic pipe supplier just half an hour’s cycle ride from Benodet and we were back in business.

However as we tested it we discovered the unsettling fact that as the autohelm steered the boat, the entire lazarette floor moved from side to side! On investigation it transpired that although the boat was built with webs moulded into the hull for the ram, whoever had installed the ram had bolted it to the plywood floor rather than the mounts! Whilst the ram was mounted very securely to the plywood floor, the plywood floor was only held in place by a few lightweight screws. We fixed this by manufacturing a stainless bracket and mounting this directly to the webs on the hull. A permanent rigid solution with the added bonus that the floor can now be lifted to examine the autohelm without disturbing it.

In 2015 as we headed out across the channel the actuator on a solenoid valve failed on the ram. A quick easy fix once we obtained the parts, but of course obtaining parts when cruising is not always easy or quick. Luckily we had visitors flying out and they were able to bring a replacement with them. We started what has become a trend for us at that time – we bought two activators so we now have a spare!

Which leads us to the failure in Biscay. The ram is attached via a rose joint to a pin on the quadrant. When new the pin is no doubt a tight fit in the hole and remains perpendicular (well almost) to the thrust of the ram, so there is little if no tendency for the rose joint to work its way up the pin. Despite this, why the manufacturers decided to prevent the rose joint being able to come off the pin with a split pin less than 1.5mm diameter I cannot understand, but what we do know, is that after many thousand miles the pin had worked its way a little loose in the hole, so it could tilt over a little and the repeated forces on the ram had pushed the rose joint up the pin shearing the split pin allowing the rose joint to work its way off the top of the pin.

We decided to take a belt an braces approach to fixing this which basically involved a new pin that fitted the hole, with a plate on top bolted down so it couldn’t be lifted and a much more beefy split pin for good measure. It may be overkill but it certainly shouldn’t fail again!

Stainless Plate
Fabricated Stainless Plate
Quadrant Pin
The new pin, plate and split pin installed on the quadrant

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