Hydraulic steering

single

single

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Boat-Colvic Atlanta 32
Long Keel
Vetus twin helm hyd. steering.

This has been a problem for years and looked at by various people but still not fixed.The steering is heavy to operate from either wheel but if the ram is disconnected from the rudder its smooth (rudder and wheel) The ram seems ok but when its all linked together its a nightmare to turn.Any other ideas?
I replaced rudder bushes and packing and still the same.Swapped steering pumps.Bled system loads of times.
 
Seized rod-eye bearing?
Ram misaligned to shaft?
Try assembling ram and quadrant leaving bolts slack, observe steering action and you should be able to identify where the problem lies.

Remember the 'fixed' end of the ram also has to pivot as the ram extends.
 
Last edited:
NorthUp said:
Seized rod-eye bearing?
Ram misaligned to shaft?
Try assembling ram and quadrant leaving bolts slack, observe steering action and you should be able to identify where the problem lies.

Remember the 'fixed' end of the ram also has to pivot as the ram extends.
Click to expand...

My guess is the ram but typically its the hardest plave to get at. Do any places do re-con vetus rams?
 
single said:
Boat-Colvic Atlanta 32
Long Keel
Vetus twin helm hyd. steering.

This has been a problem for years and looked at by various people but still not fixed.The steering is heavy to operate from either wheel but if the ram is disconnected from the rudder its smooth (rudder and wheel) The ram seems ok but when its all linked together its a nightmare to turn.Any other ideas?
I replaced rudder bushes and packing and still the same.Swapped steering pumps.Bled system loads of times.
Click to expand...

I had heavy steering on a Prout cat which was made worse when I reduced the gearing from 3 turns lock to lock to two. I reckoned that the main issue was the viscous flow of the oil through narrow pipes. I wasnt able to replace the pipes with bigger ones so I repaced the SAE 40 hydraulic oil ( thats the usual viscosity) with SAE 10 oil. Made a very significant difference.
 
single said:
My guess is the ram but typically its the hardest plave to get at. Do any places do re-con vetus rams?
Click to expand...

I had a ram of unknown make, but linked to a Vetus pump and relief valves reconditioned by a company at Hillington, outside Paisley.
The cylinder was reamed and new seals fitted, one of which had to be bespoke manufactured. Total cost was about £80 and it took about a week with me delivering and collecting.
Nicol and Andrew. Website: www.hydraulic-ram.co.uk
0141 882 4724.
 
Thanks for replies, i will refill the system with new oil (current bottle just says 'hyd steering' on it so no idea what viscosity it is! AND remove ram and service it. Main thing is making it light enough so the Autoherm st4000 works.
 
single said:
Thanks for replies, i will refill the system with new oil (current bottle just says 'hyd steering' on it so no idea what viscosity it is! AND remove ram and service it. Main thing is making it light enough so the Autoherm st4000 works.
Click to expand...

What colour is the fluid? If it is pink/red it will be automatic transmission fluid. My Hynautic system on the Prout ran on this. It is not viscous at all. If this is the case then I doubt this is the cause of your stiff steering. My system was not stiff at all and it was a single ram moving two large rudders.
 
You should be running 22cSt hydraulic oil in your system- something like Tellus T20 or thereabouts. Is your system OEM or is it an aftersale fitment? Have you possibly got a model number for the components, because the system could possibly be rather under-gunned. How does the tiller-arm feel without the cylinder connected?
Sorry for all the questions!
 
the vetus catalogue tells you how to select rams and pumps and you need to make sure you have a matched pair with the right bore of tube in between. May be worth checking what you have and seeing whether it looks like an odd match.

I fitted a new system to my HR Rasmus which is similarly sized and feel very little load.

How many turns does you wheel take end to end.

I agree with Adamaster you may have insufficient mechanical advantage. Simplest way would be to beef up the cylinder to introduce more power to the rudder in exchange for more turns at the wheel.

Can you easily swing the rudder when disconnected. Try the EM tiller and see how heavy it feels.
 
Loads of questions,I will try to answer them.The existing fluid is red and looks like autobox fluid.
I think its 3.5 turns lock to lock.
All is smooth on EM tiller without ram.
No notchy feeling in either pump.Still the same with one pump isolated.
For specs,bore size etc. i will need to check.
Ram end bearings move ok.
I'm tempted to try another ram but its a bit of an expensive gamble!
 
Red oil is automatic transmission fluid and is the usual oil for hydraulic steering - not very viscous. It is possible that a previous owner has topped it up with another more viscous oil.
 
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