Reply
 
Thread Tools Display Modes
 
Old 12-19-2015, 10:07 PM   #21
Guru
 
City: kemah
Country: USA
Join Date: May 2015
Posts: 997
Quote:
Originally Posted by Capt.Bill11 View Post
You don't have to have one or the other. You keep the mechanical pump as your main pump and plumb the electric (it doesn't have to be a Walbro) so you can valve it in and out of the fuel line system as needed.
When (if) the diaphram cracks on the mechanical it can flood the crankcase with fuel. That is impossible to do with the walbro or any external pump.
__________________
Advertisement

what_barnacles is offline   Reply With Quote
Old 12-19-2015, 10:37 PM   #22
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Country: USA
Vessel Name: Carquinez Coot
Vessel Model: 2011 Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 10,262
A small pump for now-disconnected fuel polisher is plumbed to prime the engine (as well as to transfer fuel among tanks), assisting the engine-housed thumb pump.

__________________

__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 12-20-2015, 12:33 AM   #23
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,422
Quote:
Originally Posted by what_barnacles View Post
When (if) the diaphram cracks on the mechanical it can flood the crankcase with fuel. That is impossible to do with the walbro or any external pump.
That doesn't change the fact that you can have both pumps if you wish.

Besides, failure of the mechanical fuel pump on a Lehman is fairly uncommon. At least that is what I've found in my 30+ years of dealing with them.
Capt.Bill11 is offline   Reply With Quote
Old 12-20-2015, 03:16 AM   #24
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Replacing the FL120's engine-mounted, multi-piece CAV canister filter setup with the spin-on adapters and spin-on filters makes it much faster to blleed the fuel system after a filter change because the spin-ons can be filled with fuel before installing them.

I hated the original CAV setup and when Bob Smith told me one day about the spin-on adapters jumped at the chance to ditch the CAVs once and for all. According to Bob it's one of the four best improvements that can be made to an FL120.
Attached Thumbnails
Click image for larger version

Name:	image.jpg
Views:	72
Size:	115.3 KB
ID:	47492  
Marin is offline   Reply With Quote
Old 12-20-2015, 04:13 AM   #25
Dauntless Award
 
Wxx3's Avatar
 
City: New York, NY
Country: USA
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,312
Quote:
Originally Posted by Bay Pelican View Post
Several Lehman owners, including myself, have put a 40gph Walbro pump into the fuel supply system for the Lehman. Thus when I have to bleed the Lehman I turn on the electric pump and the fuel flows.

My set up allows me to bypass the electric pump or have it on line depending on what I am doing. Thus it can serve as a replacement for the on engine fuel pump if necessary.

A third virtue of the electric pump is that it allowed me to temporarily overcome an air leak in the system by virtue of the pressure from the pump.
Yep, I also have done exactly that.

To clarify, it is plumbed as an extra loop in the line, so under normal conditions, it's still gravity feed, but when changing filters, I close the one valve and open the two in the loop so the pump, pressures the system.

Even with all my fuel shenanigans, I've never had to prime injection pump.
__________________
M/Y Dauntless, New York
a Kadey Krogen 42 Currently https://share.delorme.com/dauntless
Blog: https://dauntlessatsea.com
Find us: https://share.delorme.com/dauntless
Wxx3 is offline   Reply With Quote
Old 12-20-2015, 08:26 AM   #26
Senior Member
 
catalinajack's Avatar
 
City: Edgewater, MD
Country: USA
Vessel Name: Catalina Jack
Vessel Model: Defever 44
Join Date: Nov 2011
Posts: 354
Quote:
Originally Posted by what_barnacles View Post

I would buy a spare walbro.

When it fails you just stop. When the mechanical fails it can flood your crankcase with fuel.
Which is another reason I bypassed the mechanical pump. I think I even have a spare one aboard which I should sell to be replaced with a spare Walbro.
catalinajack is offline   Reply With Quote
Old 12-20-2015, 08:29 AM   #27
Senior Member
 
catalinajack's Avatar
 
City: Edgewater, MD
Country: USA
Vessel Name: Catalina Jack
Vessel Model: Defever 44
Join Date: Nov 2011
Posts: 354
Quote:
Originally Posted by Marin View Post
Replacing the FL120's engine-mounted, multi-piece CAV canister filter setup with the spin-on adapters and spin-on filters makes it much faster to blleed the fuel system after a filter change because the spin-ons can be filled with fuel before installing them.

I hated the original CAV setup and when Bob Smith told me one day about the spin-on adapters jumped at the chance to ditch the CAVs once and for all. According to Bob it's one of the four best improvements that can be made to an FL120.
Did this too. It is a tremendous improvement. Between the Walbro pumps and the spin-ons, the process is now quite simple. Plus, you don't have to mess with the top and bottom square o-rings.
catalinajack is offline   Reply With Quote
Old 12-20-2015, 09:26 AM   #28
TF Site Team
 
Bay Pelican's Avatar
 
City: Chicago, IL
Country: USA
Vessel Name: Bay Pelican
Vessel Model: Krogen 42
Join Date: Oct 2007
Posts: 2,787
Quote:
Originally Posted by Marin View Post
Replacing the FL120's engine-mounted, multi-piece CAV canister filter setup with the spin-on adapters and spin-on filters makes it much faster to blleed the fuel system after a filter change because the spin-ons can be filled with fuel before installing them.

I hated the original CAV setup and when Bob Smith told me one day about the spin-on adapters jumped at the chance to ditch the CAVs once and for all. According to Bob it's one of the four best improvements that can be made to an FL120.
Replaced the multi-piece CAV canister filter setup with a Racor 500 filter assembly, thus using the same filters cartridges for both secondary and primary fuel filters. Also very easy to change and monitor.
__________________
Marty
Bay Pelican is offline   Reply With Quote
Old 12-20-2015, 09:40 AM   #29
TF Site Team
 
Larry M's Avatar
 
City: JAX, FL
Country: USA
Vessel Name: Hobo
Vessel Model: Krogen 42-120
Join Date: Nov 2008
Posts: 5,734
Quote:
Originally Posted by Capt.Bill11 View Post
You don't have to have one or the other. You keep the mechanical pump as your main pump and plumb the electric (it doesn't have to be a Walbro) so you can valve it in and out of the fuel line system as needed.
Very easy. Use one 3 way valve or two ball valves on either side of the electric pump.
Larry M is online now   Reply With Quote
Old 12-20-2015, 09:50 AM   #30
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,422
Changing to spin ons is a great improvement. You can also make the engine mounted filters self bleeding like on the 135 Lemans.
Capt.Bill11 is offline   Reply With Quote
Old 12-20-2015, 10:03 AM   #31
Guru
 
City: kemah
Country: USA
Join Date: May 2015
Posts: 997
Quote:
Originally Posted by Capt.Bill11 View Post
That doesn't change the fact that you can have both pumps if you wish.

Besides, failure of the mechanical fuel pump on a Lehman is fairly uncommon. At least that is what I've found in my 30+ years of dealing with them.
fairly uncommon is a wonderful statistic unless you're the one with the failed pump.

what_barnacles is offline   Reply With Quote
Old 12-20-2015, 10:03 AM   #32
Guru
 
City: kemah
Country: USA
Join Date: May 2015
Posts: 997
But back to the original task, priming the filters. This guy did it like this and it appears to be a very simple way. (look for the funnel pic)
The Trawler Beach House: Ford Lehman Diesel Oil And Filter Change
what_barnacles is offline   Reply With Quote
Old 12-20-2015, 10:49 AM   #33
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,422
Quote:
Originally Posted by what_barnacles View Post
fairly uncommon is a wonderful statistic unless you're the one with the failed pump.
True.

But then I don't bother wearing a helmet when I'm walking under coconut palms either. I just play the odds and look up once in a while.
Capt.Bill11 is offline   Reply With Quote
Old 12-20-2015, 11:04 AM   #34
Veteran Member
 
City: Channel islands ca
Country: Usa
Vessel Name: Lillie Ruth
Vessel Model: 78 Grand banks 36 classic
Join Date: Apr 2012
Posts: 31
spin on filters

marin:
Bob seems to be a bit wobbly with his advice. When I took his class the conversion to spin on filters came up and he discounted the whole idea. He said the original filters were easy enough and 1/5 the price of spin on filters.

On my boat the PO installed an electric pump for priming / bleeding. Works perfectly. I would not fill spin on filters to speed up bleeding. You could introduce dirt directly to the injection pump. Nigel Caulder slams this idea pretty hard.

Dan
Dan Cahn is offline   Reply With Quote
Old 12-20-2015, 01:08 PM   #35
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Quote:
Originally Posted by Dan Cahn View Post
I would not fill spin on filters to speed up bleeding. You could introduce dirt directly to the injection pump. Nigel Caulder slams this idea pretty hard.

Dan
There's ton of armchair theory out there about boating, engines, anchors, you nene it. I pay zero attention to any it, only to things that have been proven to be valid. While Nigel Calder's theory is certainly plausible I know scads of people who prefill fuel filters before installing them and never heard of a problem. We've had ours for about 16 years now and never had a problem. In addition to Bob's suggestion about the spin-on conversion it was also advised by the highly experienced snd reputable diesel shop in our harbor.

If one uses clean fuel from a clean container Calder's theory is no more than that. An astroid could land on our boat and sink it, too. I give equal consideration to both theories.
__________________

Marin is offline   Reply With Quote
Reply

Thread Tools
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





All times are GMT -5. The time now is 09:16 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012