Mathers 2006 34 Mainship Trawler runaway engine

[Michaelmcp1]

Iexperienced this last Sunday my Port stalled and starboard excelerated full speed ahead.I was lucky enough to miss all the boats in the marina,

 

[Mainship Pilot]

Whoa! Glad you had control! I saw an express boat in Avalon Harbor at Catalina Island have a runaway, he ran it into the rocks vs taking out the boats in the harbor. It was pretty scary, and fast thinking!

 

[Blissboat]

Several threads on Trawler Forum discuss MMC (Mathers MicroCommander) control issues. Enter "Mathers" or "MMC" as a search term and you'll read about similar experiences.

MMCs are sensitive to voltage, so that's a likely place to start troubleshooting. But it can be frustrating and, as you realize, even dangerous. I know of boaters who, after losing confidence in the controls that came installed on their boat, have torn out their MMCs and replaced them with alternative electronic controls or even old school cable shifters and throttles.

 

[Choices]

Diesel engines can run on combustible fumes. WD40, solvents, gasoline vapors.

Only way to stop it is suffocation

Iexperienced this last Sunday my Port stalled and starboard nlyexcelerated full speed ahead.I was lucky enough to miss all the boats in the marina,

 

[SIBERNUT]

Diesels can runaway on their own lube oil if rings are bad.
CO2 fire extinguisher or cut off air..

 

[Blissboat]

The OP's choice of Forum and subject line led me to read this post as relating to MMC controls.

 

[salish]

Iexperienced this last Sunday my Port stalled and starboard excelerated full speed ahead.I was lucky enough to miss all the boats in the marina,

Curious about which model actuator miss behaved, 314. 580. 585CE, etc. I was involved with the product when it was first introduced by the Mathers family (they sold to ZF). Last I heard a dedicated battery was strongly advised.

 

[DavidM]

I used to own a 34T and had some problems with the ZF Mathers unit. Mainship issued a bulletin saying that the problem was low voltage in the DC supply to the unit. They recommended replacing the relay with a heavier one.

I never did that but Mainship’s recommendation makes sense.

David

 

[Raffy]

I have been installing the Mathers MicroCommanders for over the last 30 years and most of the failures I have seen have been associated with poor installations or bad power supply. The 2006 Mainship should have the new 9110 units installed on them along with a APS (auto power selector). There were some wiring issues with the Mainship and some bad relays. When I go to the Mainships I rewire the power supply so we feed two 10 amp breakers from the APS. We eliminate the relays and use the breakers to turn the units on and off (the KISS method, Keep It Simple). Now with your issues first of all the ZF controls can never turn off an engine, we can keep it from starting via the neutral safety switch. But once the engine is running we only control the shift and throttle functions. As far as your second issue with throttle up again it could be a power issue or a worn control head pot. Normally if the pot is worn you will get some early warnings such as having a hard time to take control of the unit, fluctuating rpm, or even and alarm coming from the control head and error messages on the LED screen on the MicroCommander itself. If you would like to contact me I will be glad to help you do some troubleshooting of the system. My number is 904-260-9756.