Rigid boom vang - any maintenance required?

cmedsailor

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My boat has a sparcraft rigid boom vang. Besides the usual washing with fresh water from time to time is any other kind of maintenance required? Do I ever need to disassembly it and grease the spring inside?
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Norman_E

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If it is anything like mine it does not have a spring, but has a gas strut (or two gas struts) inside.

Whilst no maintenance is needed, it is a good idea to examine it occasionally. Haul the boom up as far as it will go and remove the strut. Take out the screws holding the end cap at the bottom, and the plastic collar round the top of the outer tube, and pull it apart. If there is any free movement or signs of oil leakage from the gas struts, they need replacing, which is straightforward. Remove the split pins and take out the clevis pins holding the gas strut in place. Even if the struts are OK taking it apart allows you to clean out any dust and dirt that has entered. I think silicon spray is the best lubricant to stop squeaks, because oil or grease attract dust and grit.

On my one the boom was heavy to haul up, and the cause proved to be two totally shot gas struts, which I am replacing with a single, larger diameter one of the same spring rate as the combined pair. When you install gas struts remember that they must go "rod down", not "rod up", to prevent the seals drying out and allowing the gas to escape.
 

Norman_E

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It will be a gas strut, or two, depending on size. My own vang is an Ocean model and is made in such a way that one or two struts can be fitted. Each end fitting has three 8mm clevis pin holes. Each strut in mine had a force of 1150 newtons, and I am going to fit a single 2300 newton strut when I return to the boat in April. To fit this I will open out the central holes to 10mm.
 
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