Old Autohelm 3000

[GrahamAD]

Hi
I followed a thread about 2 years ago about adding a remote to an "old" Autohelm 3000. I picked up on it because of the "old" thinking I would find something usful about my 3000. However, my 3000 is even older than the model referred to in that thread! The control box on mine is sort of cylindrical shaped and is operated by turning a knob on the top. It must be about 35 or more years old and is still going strong, but has recently developed a fault in the power cable causing the unit to work intermittently. I need to replace the power cable, but to do this I need to get into the control box. I am hopeless with electronics and am wondering if there is any electronic expert out there who is familiar with the model I have and can tell me how to access the inside of the box so I can change the cable.
Thanks

[Boatguy30]

I believe it's also a 4 conductor cable on these to a special motor not used in the somewhat newer square box controller. The round ones are much more fussy to work on.

[GrahamAD]

Hi Boatguy30
Thanks for your post.
I think the cable you may be referring to is the cable from the control box to the motor which must have at least 3 or possibly more cores. There is no problem with that cable as far as I am aware. The power cable is the 2 core cable carrying the 12v power to the box and it is this cable that's giving me trouble. It should be entirely straightforward to replace if I could get inside the box to access the terminals, but what I don't know is how to open the box. There is a hexagonal nut underneath the box and I suspect unscrewing this may be what I need to do, but I am wary of doing this in case I might do something wrong. I wonder if you can put me right on that?

[mikecambrai]

Hi, Does anyone know where I can get perhaps a pdf copy of the manual for these very old autopilots? Happy to pay for the scanning.
This pilot with the rotating compass decal is not the same as the subsequent Raymarine ST3000 on with a separate control box with buttons etc.
thanks in anticipation,
Mike

[Wotname]

@ GrahamAD, if you post a few photos of your control box, we might be able to point you in the right direction regarding disassembly.

Usually the wires break at either end i.e. at the entry to the box or at the plug. If you are lucky, your's might have failed at the plug and if so, you only need to cut off a few inches and re-terminate the plug.

[Franziska]

Here is a huge amount of manuals from Raymarine and Autohelm:

https://m.box.com/shared_item/https%...k5tsqwv2ica3j6

Maybe you find something helpful in there?

[mikecambrai]

Thanks for your comments. This autopilot precedes Raymarine and is some 25 years old.
Unfortunately Raymarine does not publish anything about them and they were prior to Raymarine taking over the company.
I need to find someone who has one of these units and try to get a pdf copy from them.
Mike

[sailorchic34]

It might be that the darlington power transistors have partly failed. There will be four of them inside, located 2x2 close to each other. two are TIP120 and two are TIP125. If it's not the wiring replacing the 4 transistors should fix that issue


Sadly, I've never touched one of the old round analog units so can't tell you how to take it apart. I would imagine that the nut on the bottom does remove the lower case. It should not damage anything by removing it.


BTW the power transistors tend to burn out if you turn the helm while the drive is engaged. It's very common in pretty much all autohelms using an H bridge (the 4 transistors).


Edit: deleted broken link. The bottom nut does remove the whole unit.

[Franziska]

Not quite true.

Actually, if you look in the link I provided there is a section called retired manuals and in there you find also some from Autohelm.

Some of them are strangely only available in German, but as they have electronic formats Google translate should help to fix that, and, drawings and diagrams are usually understandable for to most of us.

Originally Posted by mikecambrai

Thanks for your comments. This autopilot precedes Raymarine and is some 25 years old.
Unfortunately Raymarine does not publish anything about them and they were prior to Raymarine taking over the company.
I need to find someone who has one of these units and try to get a pdf copy from them.
Mike

[capt jgw]

I have one of those and I had it apart several years ago.
Remove the label from the knob, there's a screw under it. Remove the screw and knob, then lift off the compass disc. As I recall there's a couple screws under that which should allow you to split the housing halves. Have a helper feed the cables in as you pull the guts out the top so you don't pull them loose from the board. Should be straight forward from there to check and resolder the power connections.
I did find an owners manual online but it did not cover disassembly or repair.

[GrahamAD]

Hi capt jgw
Just to initially acknowledge your potentially very helpful post. Away from boat at the moment, but will try your directions as soon as possible and report result.
Hi Wotname
Thanks to you also. Will post again when I've tried capt jgw's suggested solution. The break is as you suggest where the cable enters the box, which is why I need to access the inside of the box to fit a new (or shortened) cable.
By the way, I did undo the hexagonal nut at the base, but this revealed only an aperture which I suspect is a socket for attaching the wind vane cable. I have one of these but have never tried to use it.
Thanks to all others posting to this thread. Hope the suggestions result in Mike getting a copy of the manual. I could do with one myself!
What a great resource this is!

[mikecambrai]

I have uploaded the manual for the Analogue version of the Autohelm 3000 in pdf format. To read it clearly you will need to expand the text when you get to the print stage.
i hope that this is attached as I am not good at this technical stuff with computers. If you cannot read it let me know and we can try something else,
Mike

[Jim Cate]

From a very old memory: The screw under the label on the compass knob is the critical and hidden element just as described upthread. Do be wary of disassembling the multi position switch on the bottom. It contains detent balls and springs which are very difficult to reassemble (especially at sea... don't ask!).

Inside you will find three levels of circuit boards, held together by a kinda mickey mouse set of posts and with very m/m long thin connectors. Those connections are sometimes the source of intermittents, and contact cleaner is your friend.

It has been nearly thirty years since I had to repair one at sea, and the memory is a bit hazy, but I wish you luck with it.

Jim