I have a vetus two position steering on my cruiser on the French canals. Occasionally the steering jams almost solid. After a while loosens to enable me to steer and eventually goes back to normal. I am getting worried about this as it could be dangerous if it jammed in a difficult situation. It happened three times in three months last summer. This is the third season I have noticed it. Any help would be greatly appreciated. Vetus cannot suggest a reason or a cure. Someone has suggested changing the hydraulic fluid which is at least 10 years old (probably a lot more). Many thanks Gosh
Have a read through this little lot and see if anything rings true. If not, we'll have a think of the next stage. Good luck. http://www.yachtforums.com/forums/technical-discussion/18515-vetus-hydraulic-steering.html
Fishtigua. Thanks for pointing out that thread. Not the same symptoms but useful comment about dirty oil and old hose. That will be my first job at the beginning of the season. Change hoses and flush through oil. I could also have a look at the valves etc but am reluctant to dismantle something which I know nothing about (yet)
I recently ran a new boat on a long delivery and the port trim tab would get stuck down. Even at cruise (when there is a lot of pressure on it), it would take a long long time to retract and only to 3/4 of it's travel. Since we didn't have hoses, I checked everything, the solenoids were operating perfectly etc. We switched the hoses at the trim tab so down was up and up was down and it worked perfectly. The high pressure (European) hose going to the trim tab was bad and had a piece that was delaminating inside and blocking flow in one direction completely. Sometimes it's the things you least suspect.
I think you missed the point. The trim tab hose was an example. The inside of hoses can deteriorate and flake like fish-scale. These flakes can block the flow inside a hose. You should find two maybe three hoses back at the steering cylinder. Maybe 2 or 3 hoses behind each helm pump also. Usually changed out every 10 years for one reason or another. Not to hard to change out, good place to start. Just drain everything first and be patient when re-filling and bleeding the system.
It was an example I used for hydraulic hoses. Hydraulic steering uses the same hoses in many installations with just a larger diameter. If it's been 10 years since the oil has been flushed/changed, there is a very good chance a hose is bad and causing your issue.
Many thanks, both. My first job will be to examine the hoses and change then whether or not they appear damaged. There are well over 10 years old, probably nearer 20. I only have two short hoses - at the ram, all the rest is in solid copper. It should not be too difficult to drain the fluid and there is only one low point which I can blow through. The ram is in a separate compartment and no chance of being fouled by other equipment. The rudders are well clear of the structure.
A stuck helm station can be caused by "stuck" NRVs (non return valve). This valve takes either helm pressures and directs it to the steering clyinder. It has a piston with O ring that slides to allow fluid flow. If stuck, the helm would be "locked". Disassemble and replace O rings. Change fluid.
I have seen some helms that the piston have a spring to make it return and that has gone bad. That is another very possible piece to look at.