Raymarine Linear Drive - Repair or Replace?

[Capt.Don]

Hi, I have a 12 year old Raymarine Linear Drive, Type 1, that was part of ST5000+ package. The clutch has an intermittent problem of not engaging. I've spoken with Raymarine and their standard response is to send in for repair, at $575. I've taken this apart and cleaned all the surfaces, tried different lubricants/oil on the clutch slider/rails. There seems to be a fair amount of wear on the clutch assembly - it wiggles more than I'd expect. I can get it to work about 80% of the time. When stuck, if I tap (kick) the drive, it will engage. I've checked wiring, voltages,.... I'm convinced this is a mechanical wear issue on the clutch assembly.

A new linear drive can easily be had locally for $1600 (~$1450 on Internet) and includes manufacturer warranty. I'm debating whether to send in to repair vs. purchasing a new replacement linear drive unit.

Is it worth repairing or am I beginning the constant cycle of repair?

I have a 35' sailboat, displacement of 11,400lbs. The Raymarine documentation says add 20%, which would be 13,680. This is easily within their Type 1 12V, 22,000lb limit. Would there be any reason to go to the Type 2, which handles 33,000lbs? I think I'm well within the limits of Type 1.

Are the new units (part number M81130) compatible with my ST5000+? It looks like these are identical, with 2 small wires for clutch and 2 wires for motor. Has this unit changed much/at all over 12 years? Are the new units built better/worse, e.g., plastic gears, etc.?

The new units talk about corepack S1/S1G, X-10,.... I don't really know what I have. I do know that the ST5000+ included the compass, rudder reference and has the SeaTalk interface. I'm assuming the ST5000+ puts out the same plus/minus volts to drive the motor/clutch.

What do you think - spend $575 (plus shipping) to have Raymarine repair a 12 year old linear drive or spend $1400 and have new unit under warranty. Will the new on work? My wife thinks to buy the new one!

As usual, thank you very much,
Don

[Viking Sailor]

Don,

If you can determine which part(s) are worn it might be possible to find a clever way to do a repair, have a shop (or you) fabricate replacement part(s), or salvage the part(s) from a broken unit. It is sometimes amazing what can be done with a bit of epoxy and a file. For $575 I would surely give it a try.

Paul



P.S. - I have a bunch of old linear drives in storage. What is the part number of your unit?

[Capt.Don]

Paul,
I'm with you - to get to this point, I've experimented with different springs, polishing the rails with file/emery cloth.... It is working pretty good using McLube on the clutch rails, but still sticks once in a while. What bothers me is the amount of play/wiggle in the clutch unit against the side rails and/or center bushing. This doesn't seem right. I thought I could live with taking apart every few months and lubing with McLube. It is becoming annoying that it won't reliably engage.

Raymarine won't sell the center bushing and spring. Instead, they sell the entire clutch assembly at $275. Also I don't know if the rails, which are part of the outer shell, have worn and contribute to the problem. Before sending in for repair/buying new one, it might be worth another look. With the amount of play on the clutch, is this just the center bushing -or- outside rails?

I have a Type 1 Linear Drive circa 2000. The current part number is M81130. Per the service manual, part numbers are Z029, Z032, Z039, Z058 or Z059. I haven't seen any part numbers on the unit. Pictures are on my blog at Tartan 3500 - Intuition: Autohelm Woes

If you are offering, I would be interested in replacing parts from other units.
Don

[NahanniV]

Don't know about the mechanical side, but I would suggest you put it back together with the original springs and check the clutch circuit.

I suspect you may have an electrical problem: you say it usually works the first time or after it has been off for a while. What I suspect is that it works when your battery is at a high state of charge, but is marginal when your battery is somewhat discharged. 10v at the clutch terminals seems low to me.

What I would do is connect the clutch directly to a 12V source with a simple switch. Remove the clutch wires from the back of the control head and make up a cable to connect them to a breaker or fuse and a good ground.

Cheers,
John.

[Matt Johnson]

Originally Posted by Capt.Don

I have a 35' sailboat, displacement of 11,400lbs. The Raymarine documentation says add 20%, which would be 13,680. This is easily within their Type 1 12V, 22,000lb limit. Would there be any reason to go to the Type 2, which handles 33,000lbs? I think I'm well within the limits of Type 1.

Can't answer your other questions about the clutch, but I did debate the same issue of the Type 1 or 2 drive. We will be going offshore with a boat of about the same displacement as yours. I talked with a rep from Raymarine and also an ex Raymarine specialist that now works for the competition.... they both confirmed that the type 1 was more than adequate for our size boat. I didn’t hear from them about the gears, but I read somewhere that the newer linear drives are no longer using plastic gears, but have switched to metal. If mine was at home, I would take it apart and find out for sure.

I’m installing a new type one drive with all Simrad electronics.

[Capt.Don]

Originally Posted by funjohnson

....but I read somewhere that the newer linear drives are no longer using plastic gears, but have switched to metal. If mine was at home, I would take it apart and find out for sure.

Thanks for this - I will open up and check the gears - as I recall, they are plastic.

I spoke with Raymarine again to verify if the new drives are compatible with my old ST5000+ control unit. The rep said these drives have not changed "much" in 19 years and will work. Confirmed that my displacement, even fully loaded, is well within specs of the Type 1 drive. The rep also confirmed my belief that it is mechanical clutch issue - the key point is if I tap/kick the unit the clutch engages. While I agree that low voltage could be a cause, this would be repeatable as opposed to intermittent. There's no difference in voltage at control head and linear drive. One other interesting point - I mentioned that the boat had been to Hawaii - the rep came back with this is a "high-mileage" unit. That surprises me, 14 days to Hawaii plus whatever local cruising was done by previous owner doesn't strike me as high usage.

I'm still undecided whether to live with it, purchase clutch assembly, send to Raymarine for rebuild, or purchase new. Right now I'm thinking back to purchasing the clutch unit and take my chances. Metal gears might push the argument to purchasing a new one.

Don

[NahanniV]

Perhaps it is a mechanical issue, but I would still check the electrical, bypassing the control unit, before you start replacing expensive components.

Remember the clutch is an electro-mechanical device. The force it can exert is proportional to the voltage supplied to it. I don't think that the fact you can "help" it to engage with your boot rules out an electrical problem.

If I am making a 14 day passage I would hope to only engage the autopilot once. Once engaged, the clutch should not be wearing.

If you have plastic gears, you can replace them.

Cheers,
John.

[bazzer]

Whilst you are very good at taking it apart, you might be barking up the wrong tree, how do you know it's not the 5001? Why don't you bite the bullet and get a pro out to the boat and tell you what it needs? Yes, it's likely to be the mechanical part, but not necessarily,
Do you really want a failure out in the middle of a major cruise? I'd buy the new drive unit if that's the problem.
Best of luck...

[Matt Johnson]

Originally Posted by Capt.Don

Thanks for this - I will open up and check the gears - as I recall, they are plastic.


Don

If you talk to Raymarine again, I would ask them about the gears. I searched google for this info and came-up with a few websites forums saying that the plastic gears are no longer used in the linear drives. Here is a quote from sailboatowners.com:


"The plastic gears are no longer available. They only lasted me 6-10,000 miles each. You can use synthetic grease on those and extend their life. The new(er) metal gears are about $200 U.S. and should last the life to the drive." -Brian Woloshine

Of course this is talking about replacement gears, but I also read that is what is being used by the factory.

[Matt Johnson]

Originally Posted by bazzer

Whilst you are very good at taking it apart, you might be barking up the wrong tree, how do you know it's not the 5001? Why don't you bite the bullet and get a pro out to the boat and tell you what it needs? Yes, it's likely to be the mechanical part, but not necessarily,
Do you really want a failure out in the middle of a major cruise? I'd buy the new drive unit if that's the problem.
Best of luck...

Why just buy a new unit if this one can be fixed to work as well as new?

[DeepFrz]

I second (or is it third) the suggestion to check all of your electrical connections. One of the crimps in your picture looks suspect to me. It could be a matter of corrosion in an electrical connection reducing the voltage to the clutch. Critically inspecting and checking all electrical connections is a good thing to do periodically anyway.

[Capt.Don]

The key difference between rebuilding vs. new is a 6 month vs. 3 year warranty.

[Capt.Don]

Based on several suggestions that it might be electrical, before servicing or buying a new unit, I will replace the clutch wiring. In rethinking about this, there is an unknown splice from the blue/brown clutch wires (with small connectors) to red/yellow pair running to the clutch's small gauge red/black This would be 3 different wire sizes and 2 splices possibly 5-10 years old. I do have small push-on spade connectors so I should be good to replace the wire. That would rule out wiring and unknown splice in the circuit.

Thanks for helping refocus on other possible causes.
Don

[NahanniV]

When you are replacing the clutch wiring it would be very easy to try temporarily operating the clutch from a 12v source, bypassing the control head.

Cheers,
John.

[Viking Sailor]

Don,

Sorry for taking so long to get back to you - it has been a busy day. I wasn't able to find the raymarine type 1 or 2 linear drive. I must have gotten rid of it somewhere along the way. I did find three other units. Unfortunately none seems likely to be usable by you.

Best of luck,

Paul