Reply
 
Thread Tools Search this Thread Display Modes
 
Old 07-14-2021, 02:37 PM   #1
Veteran Member
 
City: Puyallup, WA
Join Date: Jan 2018
Posts: 93
Connecting a auto excited alternator to Lehman 120

Hey guys ..
I had to replace my alternator and went with a Leece Neville MR8 90 amp alternator. It does not have a connection to connect to my oil pressure switch on my Ford Lehman 120. Can someone explain how I should connect the pressure switch?
Mgtgrafix is offline   Reply With Quote
Old 07-14-2021, 05:28 PM   #2
Moderator Emeritus
 
Comodave's Avatar
 
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,185
What regulator do you have? Some of the smart regulators have a time delay before they start putting out a charge in order to let the engine get running.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you aren’t one, there is no explanation possible.
Comodave is offline   Reply With Quote
Old 07-14-2021, 05:33 PM   #3
Veteran Member
 
City: Puyallup, WA
Join Date: Jan 2018
Posts: 93
I do not have a regulator
Mgtgrafix is offline   Reply With Quote
Old 07-15-2021, 05:47 AM   #4
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
The wire to power the field terminal is usually used as an off/on switch.
FF is offline   Reply With Quote
Old 07-15-2021, 07:10 AM   #5
Guru
 
psneeld's Avatar
 
City: Ft Pierce
Vessel Name: Sold
Vessel Model: Was an Albin/PSN 40
Join Date: Oct 2011
Posts: 28,143
Pretty sure you no longer connect it to the Oil switch.


I dont.


Just battery, negative and tachometer to one of the small AC posts if you have that kind of tach.


Now you can use the oil pressure switch for an electric fuel pump possibly.


Note: I since replaced the too small black DC neg wire as it showed signs of heat stress after a couple hundred hours.
Attached Thumbnails
20170612_135301.jpg   20170612_135345.jpg  
psneeld is offline   Reply With Quote
Old 07-15-2021, 10:26 AM   #6
Veteran Member
 
City: Puyallup, WA
Join Date: Jan 2018
Posts: 93
Quote:
Originally Posted by psneeld View Post
Pretty sure you no longer connect it to the Oil switch.


I dont.


Just battery, negative and tachometer to one of the small AC posts if you have that kind of tach.


Now you can use the oil pressure switch for an electric fuel pump possibly.


Note: I since replaced the too small black DC neg wire as it showed signs of heat stress after a couple hundred hours.
Could you show a pic of your oil pressure switch and what it is connected to? I still have the connection to the buzzer but do I just not connect the other wires?
Mgtgrafix is offline   Reply With Quote
Old 07-15-2021, 10:49 AM   #7
Guru
 
psneeld's Avatar
 
City: Ft Pierce
Vessel Name: Sold
Vessel Model: Was an Albin/PSN 40
Join Date: Oct 2011
Posts: 28,143
My oil pressure switch that connected to the alternator was not connected to anything else. So now it just sits there with nothing connected to the terminals.


So I have no idea how your setup is wired and without seeing it I cannot suggest anything.
psneeld is offline   Reply With Quote
Old 07-15-2021, 11:54 AM   #8
Moderator Emeritus
 
Comodave's Avatar
 
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,185
The oil pressure switch that is connected to the alternator isn’t for the oil pressure alarm. It is there so the alternator doesn’t load the engine while it is starting. It stops the alternator from putting out current until the engine gets running and has oil pressure.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you aren’t one, there is no explanation possible.
Comodave is offline   Reply With Quote
Old 07-15-2021, 01:24 PM   #9
Veteran Member
 
City: Puyallup, WA
Join Date: Jan 2018
Posts: 93
Quote:
Originally Posted by Comodave View Post
The oil pressure switch that is connected to the alternator isn’t for the oil pressure alarm. It is there so the alternator doesn’t load the engine while it is starting. It stops the alternator from putting out current until the engine gets running and has oil pressure.
Oh ok. I will be down at the boat tomorrow so I will snap a pic. But it sounds like I can just keep it disconnected. Should I disconnect the buzzer wire?
Mgtgrafix is offline   Reply With Quote
Old 07-15-2021, 03:47 PM   #10
Guru
 
psneeld's Avatar
 
City: Ft Pierce
Vessel Name: Sold
Vessel Model: Was an Albin/PSN 40
Join Date: Oct 2011
Posts: 28,143
Why don't you take a picture for us to see what you have. Without it everyone is just guessing. Make sure we can see all sensors from alternator to starter.

My oil pressure switch was right behind the alternator. The pressure switch and alarm sensor for the instrument guage panel are further aft under where the air intake is.
psneeld is offline   Reply With Quote
Old 07-15-2021, 03:54 PM   #11
Veteran Member
 
City: Puyallup, WA
Join Date: Jan 2018
Posts: 93
Will do. I will take a pic tomorrow
Mgtgrafix is offline   Reply With Quote
Reply

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 03:29 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012