Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-06-2017, 07:39 AM   #1
Member
 
City: Newport News, VA
Vessel Name: Vitamin Sea
Vessel Model: Mainship 34 Trawler
Join Date: Jun 2017
Posts: 5
Angry Mainship 34 wiring

On my Yanmar 370 engin there is a small box, about the size of a pack of cigarettes, with 7 wires all entering on the same end of the box. It is hanging by these wires near the raw water pump and the heat exchanger. These wires have gotten wet and are corroded. Can anyone tell me what this box is or does? This may be preventing me from starting the engin.
__________________
Advertisement

Vitamain Sea is offline   Reply With Quote
Old 06-06-2017, 07:41 AM   #2
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Join Date: Oct 2007
Posts: 14,621
Greetings,
Welcome aboard. Sounds like a PFM box to me.
__________________

__________________
RTF
RT Firefly is offline   Reply With Quote
Old 06-06-2017, 09:01 AM   #3
Member
 
City: Newport News, VA
Vessel Name: Vitamin Sea
Vessel Model: Mainship 34 Trawler
Join Date: Jun 2017
Posts: 5
Quote:
Originally Posted by RT Firefly View Post
Greetings,
Welcome aboard. Sounds like a PFM box to me.
I'm a Newbe so what is a PFM?

Lloyd
Vitamain Sea is offline   Reply With Quote
Old 06-06-2017, 09:42 AM   #4
Valued Technical Contributor
 
DavidM's Avatar
 
City: Litchfield, Ct
Join Date: Aug 2012
Posts: 5,600
Which model Mainship 34, the 34T or the Pilot 34? Which year? Is your Yanmar maybe one of the new electronically controlled engines?

I owned a 2006 34T years ago and currently own a 2003 P34, both with Yanmar 370s and I am quite sure that neither have/had the box you describe. I sounds like something added on for the newer electronic engine but i can't believe that Yanmar would just let a box dangle by its wires. So maybe it is a boat builder added device but I can't imagine what.

On further thought, since it is right below the alternator could the PO have added a high output alternator and this box is an external regulator like a Balmar? Do the wires run up to the alternator?

Finally, why did the wires get wet? Your raw water pump seal may be leaking or maybe a hose clamp needs tightening.

David
DavidM is offline   Reply With Quote
Old 06-06-2017, 09:54 AM   #5
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Join Date: Oct 2007
Posts: 14,621
Greetings,
Mr. VS. My humblest apologies. Yes, you are a Newbe and I should have been more sensitive. PFM box? The wires go in and the wires come out. What happens inside is Pure "Freakin'" Magic. In other words, I have no idea. Again, apologies...

__________________
RTF
RT Firefly is offline   Reply With Quote
Old 06-06-2017, 11:29 AM   #6
Guru
 
Lou_tribal's Avatar
 
City: Quebec
Vessel Name: Bleuvet
Vessel Model: Custom Built
Join Date: Jan 2016
Posts: 4,036
Did you try to follow the wires to find out from where them come and where they are going?

L.
Lou_tribal is online now   Reply With Quote
Old 06-18-2017, 10:08 AM   #7
Member
 
City: Newport News, VA
Vessel Name: Vitamin Sea
Vessel Model: Mainship 34 Trawler
Join Date: Jun 2017
Posts: 5
The small box turns out to be a glow plug controller. Found a new one on eBay but could not find a matching connector so I ordered the entire harness. In the meantime I crimped spade connectors on the wires and plugged them in. Still no luck in getting power to the starter system. With help we found that there were two splices down in the bilge that were corroded. Replaced them and everything is now working. Thanks for the feedback.
Vitamain Sea is offline   Reply With Quote
Old 06-18-2017, 11:08 AM   #8
Valued Technical Contributor
 
DavidM's Avatar
 
City: Litchfield, Ct
Join Date: Aug 2012
Posts: 5,600
Glow plug controller??? The Yanmar 370 hp 6LY-STP doesn't have glow plugs. Maybe you mean the air preheater. But Yanmar certainly didn't build that engine with the controller hanging free by its wires.

Maybe some boat builder or previous owner?

David
DavidM is offline   Reply With Quote
Old 06-22-2017, 04:31 PM   #9
TF Site Team
 
Bacchus's Avatar
 
City: Seneca Lake NY
Vessel Name: Bacchus
Vessel Model: MS 34 HT Trawler
Join Date: Nov 2014
Posts: 4,258
Now you have me wondering...will have to look at my 6LYA-STP.
Seems odd the pre heat controller would be port side near water pump when heaters are on Stbd????
__________________

__________________
Don
2008 MS 34 HT Trawler
"Bacchus"
Bacchus is online now   Reply With Quote
Reply

Tags
mainship 34, yanmar 370 wiring

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 08:48 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×