On a recent sailing trip on my friends boat his Raymarine Autopilot ST2000+ tiller pilot failed. When it was setup to steer automatically to a compass heading it just put the tiller hard over and refused to work correctly.
This was not the first time this had happened, it did the same last season, but following a recalibration of the fluxgate compass it continued to work.
I have now taken it apart and discovered the real reason for the failure is 2 rubber buffers which cushion the ram worm gear at each end of its travel had broken up and pieces of rubber were floating around inside the tiller pilot, some of these pieces had become jammed in the fluxgate compass gimbals preventing the compass from operating.
This would explain why the fault was happening intermittently, as each time the autopilot was put away the pieces would have been shaken free.
Below is a photo of the shaft end buffers after I glued the pieces back together.
On my friends behalf I contacted Raymarine to enquire about spares to replace the rubber buffers and a new seal to fit on the end of the shaft to prevent the ingress of water and salt atmosphere. The only help they could offer was to contact a local marine electronics specialist.
I did as suggested but they did not have any spares either. But did say something was needed to act as a buffer as with out the mechanism could jam on the end stops and lock up the motor. They suggested using 4 suitably sized "O" rings 1 fitted over each end of the aluminium guide shafts.
I discovered the shaft seal is a standard imperial sized one, (although rather uncommon as the size was 3/4" internal x 1" external x 1/8" thick) I finally located one on Ebay, and ordered it along with another odd sized "O" ring, 3/4" internal x 1/16" thick) which seems to act as a primary seal in the push rod shaft seal.
I joined the Ramarine help forum and made 2 posts concerning the repair of the autopilot for the benefit of others who may have had the same symptoms, the posts were not approved. Below is a reply from the moderator as to why.
My opinion of Raymarine as an organisation and the ST2000+ autopilot has changed. Considering these autopilots cost approximately £600 10 years ago, and strangely enough they still seem to be current today.
It is let down by the poor design of the mechanics, the cheap materials and lack of spares available.
Mike
This was not the first time this had happened, it did the same last season, but following a recalibration of the fluxgate compass it continued to work.
I have now taken it apart and discovered the real reason for the failure is 2 rubber buffers which cushion the ram worm gear at each end of its travel had broken up and pieces of rubber were floating around inside the tiller pilot, some of these pieces had become jammed in the fluxgate compass gimbals preventing the compass from operating.
This would explain why the fault was happening intermittently, as each time the autopilot was put away the pieces would have been shaken free.
Below is a photo of the shaft end buffers after I glued the pieces back together.
On my friends behalf I contacted Raymarine to enquire about spares to replace the rubber buffers and a new seal to fit on the end of the shaft to prevent the ingress of water and salt atmosphere. The only help they could offer was to contact a local marine electronics specialist.
I did as suggested but they did not have any spares either. But did say something was needed to act as a buffer as with out the mechanism could jam on the end stops and lock up the motor. They suggested using 4 suitably sized "O" rings 1 fitted over each end of the aluminium guide shafts.
I discovered the shaft seal is a standard imperial sized one, (although rather uncommon as the size was 3/4" internal x 1" external x 1/8" thick) I finally located one on Ebay, and ordered it along with another odd sized "O" ring, 3/4" internal x 1/16" thick) which seems to act as a primary seal in the push rod shaft seal.
I joined the Ramarine help forum and made 2 posts concerning the repair of the autopilot for the benefit of others who may have had the same symptoms, the posts were not approved. Below is a reply from the moderator as to why.
My opinion of Raymarine as an organisation and the ST2000+ autopilot has changed. Considering these autopilots cost approximately £600 10 years ago, and strangely enough they still seem to be current today.
It is let down by the poor design of the mechanics, the cheap materials and lack of spares available.
Mike
