Moderated Discussion Areas
  ContinuousWave: Small Boat Electrical
  NAVMAN 3100 Repair

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   NAVMAN 3100 Repair
jimh posted 03-30-2011 09:16 PM ET (US)   Profile for jimh   Send Email to jimh  
I came across this interesting home-movie video that describes how to make repairs to the NAVMAN 3100-series instruments, which are somewhat infamous for having trouble with their displays:

This repair is not for the faint of heart.

Also, there is more information about repairs in this thread:

One suggestion is to dry out the display in a warm, hot, dry place, which seems to help remove moisture.

6992WHALER posted 04-02-2011 10:16 AM ET (US)     Profile for 6992WHALER  Send Email to 6992WHALER     
Jim, I found this video last fall, I have the part and I am going to try the repair this spring.


Peter posted 04-04-2011 08:37 PM ET (US)     Profile for Peter  Send Email to Peter     
Interesting. A few years ago the display on my F3100 failed. Northstar sent me a new F310 for a minimal amount so I took my F3100 apart to see if I could figure out what failed. Wasn't obvious to me so I threw it away.
6992WHALER posted 08-08-2011 02:45 PM ET (US)     Profile for 6992WHALER  Send Email to 6992WHALER     
I am happy to report that the repair procedure in the video worked.
I actually did a combination of the above video and this one

I followed Terry's video except;

I cut the elastomer to 11 mm not 9mm - to get more pressure from the front cover of the unit.

I trimmed off the rubber part on the elastomer were it contacts the plastic cover so it would mate better with the circuit board. (I modified this idea from the Larry video)

I had to cut the elastomer longer than Terry because the fuel flow meter has more contacts between the LCD and the circuit board then the depth unit he was repairing.

The repair took less then one hour (not counting removal and installation of the unit)

Tools required:
-T7 torx screw driver to open the unit,
-Sharp blade to trim the elastomer, and beveled edge of plastic cover.
-Flat head screw driver or something similar to push the tabs in that hold the LCD cover to the unit.
-Small phillips head to open up the donor LCD.

Ordered the donor unit from
Part number pm-1028A Jumbo LCD DPM/9v

I just used the unit for a 350 mile cruise. I topped the tanks off twice, both times the unit and the fuel dock pump agreed on the amount of fuel used. (both times the total difference was less then 0.6 of a gallon)

The display worked perfectly.

Cost was $22.25 for the donor unit.

Northstar told me they would fix the Navman 3100 unit for $346.00. Currently you can purchase a new Northstar F310 fuel flow meter for $340.00.
The f310 was recently discontinued again.

jimh posted 08-08-2011 03:16 PM ET (US)     Profile for jimh  Send Email to jimh     
John--Many thanks for the detailed first-hand account of the repair of your NAVMAN F3100 fuel instrument. This sort of information is much appreciated.

I am sad to hear that the F3100 or F310 variant are no longer being made. This device was one of the best designed, most user-friendly, and most useful devices I have ever had on my boat. I regret removing mine, which I did only because I switched over to using my modern direct-injection outboard engine as the source of fuel flow information.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.