Autohelm 4000

Sailartist · #1 01-14-2010

I have a broken lever on my Autohelm 4000. Bought a new belt thinking it would tighten up on the gear better than the old worn out belt and keep the lever engaged but it didn't work. There is no other mechanical reason why it does not engage, or stay in the 'up' position keeping the belt tight against the gear. Does anyone know what i am talking about?
thanks
Sailartist

CaptainDan99 · #2 01-14-2010

The lever rotates a metal shaft that rotates a cam, tightening the belt. The lever is attached to the metal shaft by a drift pin. A common problem is that the pin shears off. Make sure that when you engage the lever, the metal shaft is also moving with the lever. If not, you will need to remove what is left of the old pin and replace it.

Dan
Tartan33R

JSL3 · #3 01-15-2010

I'm betting Dan has it right and your pin is broken.

Here's and older post that has a schematic of the drive mechanism, in case you haven't seen it. Link

FishSticks · #4 01-15-2010

Had that exact problem and replaced the pin many miles ago with a piece of drill bit of similar diameter.

Sailartist · #5 01-15-2010

Thanks for your reply. I believe the metal shaft and drift pin are still there. The metal shaft does move with the lever and it moves the rubber wheel closer to the gear as in tightening it, but the lever and wheel still just flops open and does not stay tight. So, maybe i am identifying the parts wrongly, but I will try to see what you are saying tomorrow. A very experienced boat friend is coming to take a look and i will give him your input.
thanks
Sailartist

Sailartist · #6 01-15-2010

I just looked at the schematic closely. I think i see what you are talking about and maybe the pin is broken between the lever and the drive wheel assembly where it does not show. This helps a lot! And we could try using a small drill bit as suggested to go all the way through whole assembly.
thanks for the help!
Sailartist

CaptainDan99 · #7 01-15-2010

If you look at the schematic in the link posted by Jim, the pin is part #6, the shaft that it fits into is part #11.

Check the movement closely, maybe by holding on to the shaft or cam and then trying to move the lever. It may grip sometimes but not move the cam fully. Mine finally broke free when the autopilot was engaged and I could not get it to turn the wheel loose!

Dan

piccadeli · #8 02-02-2010

I too had the same problem, it is actually the nylon gear that tightens the belt on the leaver. After much searching, I had one made out of aluminum. I had a couple of extras made if you are interested, they are 75.00 each.

Gary

Sailartist · #9 02-02-2010

Hi Piccadeli,
Upon close examination, we discovered that the pin that goes through the 'drive eccentric assembly' # 11 on the schematic, is definitely sheared/broken where the weld should be. The pin should be welded to the eccentric gear so it tightens and stays in place. Instead, the pin is spinning free and therefore not keeping tension on the belt. So, not sure if your part you are offering is the same. Can you look at the schematic and let me know.
thanks for your help
Sailartist.

piccadeli · #10 02-02-2010

The part I have had made is #7 the Pinion Sprocket on the schematic. The steel "t"shaped pins sits in this sprocket, and the sprocket tensions the belt.
so unfortunately the pin is not what i have.

Good Luck

Gary