Monday, August 31, 2009

Repairing a Maxwell Nilsson VR-700 windlass Part 1

Bianka came with a Maxwell-Nilsson VR-700 electric windlass to help lift and deploy it's 125 feet of chain. Since I do a lot of solo cruising it makes anchoring or weighing anchor easy for a solo sailor without crew. I'd say it is a critical piece of safety equipment if one should find the boat dragging anchor and need to weigh anchor ASAP. I've yet to drag anchor but, it's important not to think that will never happen as you can read here and here. Having the ability to lift anchor rapidly when things get nasty is rather important.

The VR-700 windlass on BIANKA worked very well for years and did not take up a lot of room on deck. It worked flawlessly until one day it failed. Calls to the manufacturers told me that this windlass was no longer made and no parts or parts diagrams were available. Also the companies Maxwell and Nilsson were now separate manufacturers and neither one had any info on my windlass. In fact I had a piece of orphaned equipment on my hands. Not looking good. But, I also was not looking forward to installing a new windlass in the deck for cost reasons but, mostly because that would mean cutting new holes in the deck. So my only option was to try an repair it myself.

The problem was the windlass shaft was still spinning but, the chain gypsy could no longer lift the chain. Not being the most mechanically inclined person I began the investigation into it's failure. The documentation I found on board on the windlass was sparse and had no parts diagram. Basically it was an installation manual that covered several Maxwell-Nilsson models. Because the motor and gearbox is mounted below decks in the chain locker and the Nonsuch mast blocks access to them. I was hoping the failure might be confined to the parts I could work on above deck. It appeared so at first. I could see that the windlass shaft was spinning but the chain gypsy was standing still. So I began by removing the rope capstan and discovered that the key that sits in the shaft was no longer sitting in the key way of the chain gypsy. As shown in the photos below:


This certainly seemed like it was the problem. Pulling off the chain gypsy I soon found why this occurred. It seems the key which appeared to be made of brass had corroded to the point were it would no longer fit securely in the key way of the chain gypsy. Aha! I thought this is surely the problem.


So now all I should have to do is find a replacement key and my chain lifting by hand days should be over. I recalled when I was on a freighter trip several years ago one of the other passengers was an engineer at the Los Alamos laboratories who was also had a hobby of building and repairing small engines known as "hit and miss" engines. He mentioned a supplier of small brass and metal parts by the same name. I looked at their website and yes the could sell me some square brass rod the same size as the key used in the windlass. But, I would have to cut it to the length I wanted. So it looked like the problem with the malfunctioning VR-700 would be quickly solved. Of course this is silly notion when working on mechanical systems on a boat. But, it often gives one the false hope that the repair will simpler than one first thought. But, the lesson learned is that even though equipment on board is working and looks pretty robust it still needs some routine maintenance. If I had looked at the above deck components earlier I could have prevented this failure from occurring in the first place.


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