ST7002 Autopilot
While we were in the Amazon Delta last month our ST7002 autopilot quit working. The unit made a loud grating noise - it sounded like spinning gears which were not fully engaged. The fly in the ointment is that the unit started out life as an Autohelm 7000. We have replaced the control head, but the computer and the type 2 long linear drive unit are the original Autohelm components. We think that the unit was manufactured around 1991 - this is based on the motor label which indicates DATE 2/90.

I dismounted and opened up the linear drive unit. The inside of the linear drive unit had a large amount of black dust - it appeared to be brush carbon, but could have come from the black plastic gears. The drive belt (300 3M 12 469D) had some wear, but it appeared to be in serviceable condition. I disassembled and inspected the components. I connected a source of 12VDC to the motor - it ran fast and smooth. The resistance between the leads of the motor is .6 ohms (measured with a Fluke Model 23 Series II digital multimeterI). I connected the 12VDC source to the clutch coil and it had a strong magnetic field. The resistance of the clutch coil is 27.3 ohms. The clutch coil seems free to slide axially on its mounting pin. Both the small motor drive gear, and the large belt driven gear on the drive shaft seem to be serviceable. When I pull the tiller arm in and out, the planetary gear unit rotates freely. However, there is quite a radial wobble in the 4 planetary gears, which allows the clutch top / planetary gear housing to have a radial wobble.

I removed the circlip on the shaft end and pulled the steel clutch plate / plastic drive gear assembly. Both the shaft bushing and the plastic ring gear teeth on the clutch appear to be serviceable. I removed the roll pin securing the brass planetary gear base to the output shaft. The wobble in the planetary gears is as a result of excessive wear of the small drive gear which engages the 4 pinion gears. The planetary gears do not seem to be excessively worn.

I called the Raymarine Technical Department and spoke with Mark - he was quite helpful. He told me that the problem was that parts are not available for units built before 1989. The motor-side of the baseplate has a three box label with the following numbers: (upper two boxes) 2029 and 12V, (the lower box) 400004. There is a label on the FRACMO motor (serial 3666/366) with "DATE 2/90" - which indicates that if the motor was manufactured in February 1990, then this unit was built sometime after that date. Attached are 10 photos for ID purposes.

Mark told me to set up an account on this forum and post the information I had so that the folks in England can try to establish the date of manufacture for this unit. Then we can order the correct replacement parts. It is my understanding that there is a bronze gear replacement kit to upgrade the plastic gears. I would like to not only replace the broken components, but anything else you think we need to do. We are headed for the Panama Canal, and it is a long way across the South Pacific. I started out my career in the US Navy as an electronics technician, so with some guidance and the needed repair parts, we ought to be able to repair the unit.
Warm regards,
Tom Service
S/V Tiger Lilly
Spanish Waters, Curacao

Views: 1386

Attachments:

Reply to This

Replies to This Discussion

I apologize for the delay, wanted to speak with our linear drive technician about your issue.

He explained that you will need planetary gear kit N021, this will come with the brass gears. He also suggested due to the age of the motor, he would recommend a new motor, and keep as a spare in case you get into any issues in the future, motor part number N002.

Are the part numbers the same for a type 1 linear drive?

Rodney,
I am the wrong guy to answer your question. I am just another boat owner who needed information from Raymarine.
You need to open a separate topic, and wait for the Raymarine technical wizzard (Underway - Raymarine, US) to answer you. It took them a couple of days to get back to me.
If you do take the same brass gear kit (N021), and you are in the Caribbean, Budget Marine carries these parts.
Tom Service
S/V Tiger Lilly
Spanish Waters, Curacao, N.A.



Rodney Kidd said:

Are the part numbers the same for a type 1 linear drive?

The brass gear kit is the same, N021.  The motor part number is different, for the Type 1 the part number is N001.

Reply to Discussion

RSS

Events

Videos

  • Add Videos
  • View All

Photos

Loading…
  • Add Photos
  • View All

Latest Activity

Andrew Mylander updated their profile
Jan 14
Randy Martin updated their profile
Jan 9
Marc Macot updated their profile
Jan 9
Humberto Ferman replied to gerald stapp's discussion Connecting Raymarine c127 to Airmar B60 transponder
"Hello., I have more or les same situation. I have a B60 transducer from Raymarine (E66085) and I want to use it with my c127 MFD. Should I just only get the adapter E66066 and plug it.?"
Jan 6
John T. Cox replied to Andre Chenier's discussion ST6002 vs ST6000+
"I have the inverse situation.  I have a ST6002 with an S2G course computer,  and I found an ST5000+ head unit in the back room that I'd like to use for a second station by connecting via seatalk.   Is that possible?   Thanks…"
Jan 6
Richard H Wheeler liked jeff hesse's discussion S1000 autopilot
Dec 3, 2016
Josh Pekar replied to Kevin Linder's discussion Cameras for e125
"I am also able to access other non-raymarine hardware through the MFD's WiFi by also assigning them within the same static IP range i.e. I can access my NVR.   Now you have a WiFi access point whenever your MFD is running.  Neat!"
Nov 17, 2016
Josh Pekar replied to Kevin Linder's discussion Cameras for e125
"Update on how to get 3rd party IP cameras to work with Raymarine settings that worked for me. 1. Must set static IP for camera in the range of 10.0.1.X** 2. Set Subnet of camera as 255.0.0.0, Gateway and DNS as 10.0.1.1 3. Disable ONVIF…"
Nov 16, 2016
Steve Battel updated their profile
Nov 16, 2016
John updated their profile
Nov 9, 2016
skipbern updated their profile
Nov 3, 2016
No Name updated their profile
Oct 27, 2016
Joe Shabbott liked Moderator - Raymarine, US's discussion Interfacing a Raystar 130 GPS Sensor to an E-Series Widescreen MFD (E90W, E120W, E140W)
Oct 23, 2016
Richard Anderson updated their profile
Oct 3, 2016
Mark noe updated their profile
Sep 12, 2016
Phil Niles updated their profile
Sep 12, 2016

© 2017   Created by Moderator - Raymarine, US.   Powered by

Badges  |  Report an Issue  |  Terms of Service