Monday, August 31, 2009


So I've found the secret of how to remove the motor from the Maxwell Nilsson VR-700 gearbox housing. It seems these circa 1986 Maxwell-Nilsson windlasses ( and I guess other models) had a roll pin inserted into one of the gear box cover screw hole to lock the threads on the motor so it would not turn and unscrew during operation. Yep, that could ruin your day to have the motor drop into the chain locker! Once this locking roll pin was moved out of the way the motor simply unscrews from the gear box housing (with only a little grunting).

MIKE'S NOTE: When backing out the motor and worm gear there were two spacers on the end of the worm gear shaft make sure you don't lose them and put them back n the shaft when reinstalling the motor.

I did go out and buy an extra tool for this repair and I highly recommend you do too if you don't it already. That is a Roll Pin punch kit. I bought mine at SEARS. But, I expect they are available elsewhere and online.
As you can see in the above photo the Roll Punch has a little nib that helps center the punch in the roll pin. You might be able to use a flat punch. But, the right tool for the right job eh? I figured I may be repairing this windlass again in the future so might as well have the right tool.

You can see in the above photo how the roll pin that locks the motor does it. It simply squeezes up against the threads. This also explains the mysterious grease spot I found on the outside of the gear case in Part 2 when I was removing the windlass from the boat. Some of the grease inside the gear box was able to migrate down though this hole. Grease mystery solved!

When I unscrewed the motor I found some damage to some of the threads. I'm not sure how or when this happened. Maybe someones previous repair attempt or during the lightning strike or because these and similar windlasses made in the eighties used the case as an electrical ground and high currents and the associated heat may have started to melt the threads. I plan to address the last issue when I reassemble the windlass.

With the motor and worm gear removed I was finally able to remove the shaft from the gear that turns it:
You can see in the above photo the jury rigged repair that some had attempted to do by inserting a smaller roll pin inside the original damaged one. It worked ... for awhile.

I then turned my attention to inspecting the gear. On one side things looked pretty good:

But on the other side... It was not a pretty picture:
This side of the gear was pretty torn up by the broken roll pins grinding away when they broke inside. The photo below shows what the gear housing damage looked like when looking at the inside of the gear:

Since I've been told by both Maxwell and Nilsson that there are no spare parts available for this orphaned windlass it limited my options. I figured I've come this far I have nothing to lose. I might as well attempt a repair. Looking at the damaged gear I will have to fill the gap in the damaged side of the gear. Hmmmmm. looks like a job for MARINE TEX GREY. I always carry a box of this stuff on board. It is an epoxy mixture that goes smoothly and is very strong when it sets. It has a compressive strength of 13,000 PSI. Which I think should be good enough for this job. It is good stuff to have around for repairs like this. A few years ago I used it to temporarily repair an exhaust elbow that develop some holes. The repair lasted almost a year. So now I have decided on what to use for the repair. The problem was how am I going to make sure that the new roll pin will line up straight after I use the Marine Tex to fill the damaged gear. Here is what I did:

First I insert a new Roll Pin through the good hole about halfway into the gear as shown above. I coated this Roll Pin with Tef Gel which I have on board for corrosion protection on screws and other hardware. It is also good stuff to have around. In this case I am using it prevent the Marine Tex epoxy from sticking to the Roll Pin. It's a "just in case" precaution.

Below is a shot of how it looks from the the other side of the gear. It looks nicely centered for the repair.

In the next step I take a common nail that will just fit inside the Roll Pin and coat it with Tef Gel too. This will help insure that I will have a straight run though the gear to the other side after I use the Marine Tex for the repair as shown below:
The next step is mix the Marine Tex and work it into the damaged side of the gear carefully without making to much of a mess. Then I will let it cure and slid the Tef Gel coated nail out easily. Then I will drill the Marine Tex side of the gear slightly so the new Roll Pin can be punched through securing the shaft to the gear once again. Like this:
Well that worked out pretty good. Now all that's needed is to insert the shaft into the gear align the gear and shaft holes and punch in a new Roll Pin.
SUCCESS! Well, I might have used a slightly larger drill bit when I drilled the the hole for the new Roll Pin as some of the Marine Tex was snapped off of the surface of the gear when I inserted the Roll Pin but, most of it stayed in place and filled the gap nicely.
So the only thing I need to do now it to reassemble the windlass fill the gearbox with new grease and install it back on the boat.
Finding the grease looked like it might also be a problem at first. In Nilsson windlasses the "Standard lubricant is Castrol “TC” which is a flowing grade 00 grease". I spent the better part of two days making calls trying to find this grease. Nobody in the states seemed to have this Castrol TC 00 grease in anything smaller than five gallon buckets. I then did some Googling for "00" grease and found that Snapper lawnmowers use "00" grease too. So I was able to by a liter bottle of Stens "00" grease for about $11.00 from a nearby lawnmower repair shop. So all in all other than my time the total repair cost (for new Roll Pins, Grease and Marine Tex) to get my Maxwell Nilsson VR-700 windlass working again was about $14.00. Which was not a bad return on my efforts since a new windlass would be a thousand bucks or more. Armed with my new knowledge of how this windlass works and the ability to maintain it it should last another 20 years.

MIKE'S END NOTES: After I had finished making the repair to my VR-700 windlass. The James Nilsson Company began offering some limited parts for their earlier windlasses. It looks like some of these parts will fit the VR-700 and other similar windlasses. You might want to contact them and see if you will be able to fit some the parts they have to your windlass. So far my repaired windlass has worked flawlessly and hope to keep it that way.
Links to previous windlass repair posts:


AC Repair Clearwater said...

That's probably cause a leak...

Capt. Mike said...

Yep, that grese spot I noticed on the bottom was in the whole were the roll pin was inserted. But, a lot of grease does not leak out.

ben_okopnik said...

Hey, Cap'n Mike -

If that MarineTex ever lets go (and in my experience with it, it does eventually), just heat up that gear with a torch and fill it with solder, then drill a hole for the pin. Of course, you'd need another pin by then...
Love your lucid illustrations and explanations, by the way! Anyone else with this windlass will consider your page a real treasure trove of useful info.

Capt. Mike said...


Thanks for the kind words. I was hoping someone would find the information useful. So far the Marine Tex has been holding up so far for about three years. Not sure solder would hold up as well though. Since lead is a preety soft metal.

Still Waters said...

I have a 1989 circa VMC-1000 (new to me and seems similiar to your 700). It has stuck a few times when hauling. It works again after tapping the motor with a hammer. I suspect I need to grease the gearbox. How did you fill the gearbox with the "00" grease? Do I have to remove the gearbox and fill from below deck or can I fill from above?

Capt. Mike said...

Still Waters:

Yes I think you will have to remove the gear box to refill it like I did. Maybe something is getting jammed in the gears and stopping the motor. So a good clean out and new grease might be a good thing to do. Another possibility there might be some contact issue with the motor so removing the windlass and cleaning the contacts or brushes(?) might be a good thing too. Hope this helps.