Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-19-2020, 12:32 PM   #1
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Fuel tank crossover line question

Hi all, I have a Jefferson 45 and have attached the photo of my fuel set up. When underway with both crossover valves port and starboard open, I lose fuel to both Mains and the generator due to starvation. After I close the starboard crossover valve and prime the engines, she fires up and everything runs great. I've read many post of folks indicating that you should run with the crossover lines open but when I seem too, I find myself down in the engine room using the manual primers to reprime. Any input would be greatly appreciated.Click image for larger version

Name:	20200919_131241.jpeg
Views:	182
Size:	52.7 KB
ID:	107998
__________________
Advertisement

Mike_M is offline   Reply With Quote
Old 09-19-2020, 12:48 PM   #2
Senior Member
 
Redhook98's Avatar
 
City: Colonial Beach, VA
Country: US
Vessel Name: Tatoosh
Vessel Model: 1979 49ft MT RPH - restored
Join Date: Jun 2019
Posts: 166
Are your fuel tank vents working correctly? Next time try it with your fuel caps off your tanks.
__________________

__________________
"Everything on your boat is broken.... You just don't know it yet."
Redhook98 is offline   Reply With Quote
Old 09-19-2020, 12:53 PM   #3
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 8,873
Mike
How difficult would it be to set up a return manifold? This way the engines and genset would return to the single tank you're drawing from. I've never liked crossovers as part or the normal operation. Mine have been shut since the boat was new.

Do the tanks have sight tubes?
sunchaser is offline   Reply With Quote
Old 09-19-2020, 12:59 PM   #4
Guru
 
Soo-Valley's Avatar
 
City: Gulf Islands
Country: canada
Vessel Name: Soo Valley
Vessel Model: Grand Banks 36
Join Date: Jul 2019
Posts: 1,325
Your drawing shows how flows should be. I would like to see a picture of the manifold? or the valve setup which shows direction of flows too.

after I close starboard valve, prime it starts
Do you then leave it closed?
__________________
SteveK
You only need one working engine.
That is why I have two.
Soo-Valley is offline   Reply With Quote
Old 09-19-2020, 01:13 PM   #5
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
I'll try it but I'm going to need to find another crew member as my wife does not like it when the boat dies out on the water... there's no statement like telling her that I swear I can get it started again, LOL
Mike_M is offline   Reply With Quote
Old 09-19-2020, 01:15 PM   #6
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
I'll try it but I'm going to need to find another crew member as my wife does not like it when the boat dies out on the water... there's no statement like telling her that I swear I can get it started again, LOL
Quote:
Originally Posted by Redhook98 View Post
Are your fuel tank vents working correctly? Next time try it with your fuel caps off your tanks.
Mike_M is offline   Reply With Quote
Old 09-19-2020, 01:16 PM   #7
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by sunchaser View Post
Mike
How difficult would it be to set up a return manifold? This way the engines and genset would return to the single tank you're drawing from. I've never liked crossovers as part or the normal operation. Mine have been shut since the boat was new.

Do the tanks have sight tubes?
Yes. The valve to the left in the picture is for the bottom vent for Sight glass and the valve to the right is the crossover valveClick image for larger version

Name:	20200919_141000.jpeg
Views:	63
Size:	58.7 KB
ID:	107999
Mike_M is offline   Reply With Quote
Old 09-19-2020, 01:18 PM   #8
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by Soo-Valley View Post
Your drawing shows how flows should be. I would like to see a picture of the manifold? or the valve setup which shows direction of flows too.

after I close starboard valve, prime it starts
Do you then leave it closed?
I can visibly Trace all the lines.Click image for larger version

Name:	20200919_140906.jpeg
Views:	54
Size:	91.3 KB
ID:	108000Click image for larger version

Name:	20200919_140811.jpeg
Views:	56
Size:	84.8 KB
ID:	108001
Mike_M is offline   Reply With Quote
Old 09-19-2020, 01:25 PM   #9
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by Mike_M View Post
I can visibly Trace all the lines.Attachment 108000Attachment 108001
Quote:
Originally Posted by sunchaser View Post
Mike
How difficult would it be to set up a return manifold? This way the engines and genset would return to the single tank you're drawing from. I've never liked crossovers as part or the normal operation. Mine have been shut since the boat was new.

Do the tanks have sight tubes?
I don't really care for the crossover option when running dual props. The fuel manifold allows me to switch tanks to keep balanced but it's never been a concern.
Mike_M is offline   Reply With Quote
Old 09-19-2020, 01:29 PM   #10
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
And yes, I leave it closed.
Quote:
Originally Posted by Soo-Valley View Post
Your drawing shows how flows should be. I would like to see a picture of the manifold? or the valve setup which shows direction of flows too.

after I close starboard valve, prime it starts
Do you then leave it closed?
Mike_M is offline   Reply With Quote
Old 09-19-2020, 01:46 PM   #11
Guru
 
Comodave's Avatar
 
City: Au Gres, MI
Country: US
Vessel Name: Never Say Never
Vessel Model: President 41 DC
Join Date: Jul 2015
Posts: 9,361
I have never opened the crossover valve on my boat. Port engine and genset run on port tank and starboard engine runs on starboard tank only. Returns go to tank supplying the engine.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you arenít one, there is no explanation possible.
Comodave is offline   Reply With Quote
Old 09-19-2020, 02:17 PM   #12
Guru
 
Soo-Valley's Avatar
 
City: Gulf Islands
Country: canada
Vessel Name: Soo Valley
Vessel Model: Grand Banks 36
Join Date: Jul 2019
Posts: 1,325
Quote:
Originally Posted by Mike_M View Post
And yes, I leave it closed.
Then I suggest that the starboard tank feed line is drawing air.

BTW is the crossover direct from tank bottom to tank bottom or is run through the top two inlets of manifold.
__________________
SteveK
You only need one working engine.
That is why I have two.
Soo-Valley is offline   Reply With Quote
Old 09-19-2020, 03:43 PM   #13
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by Soo-Valley View Post
Then I suggest that the starboard tank feed line is drawing air.

BTW is the crossover direct from tank bottom to tank bottom or is run through the top two inlets of manifold.
Thanks so much for all of the responses .

What's interesting is, I can have the boat idle for 30 minutes plus with the Genny running and then put a load and she starves out. Would you suspect that my vents may be clogged? at idle, it's not drawing as much fuel but if the vents are clogged maybe it's too much for my system when under load.

Also, would there be any harm in closing both crossover valves as I have the port open and the starboard shut and she runs fine. I left it this way as I loss both engines in 12 foot seas. At that time, I just closed the starboard cross-over valve and re-primed the mains as it was quite the Panic moment. My initial thought was, I could not have all three systems pulling from the tanks and also transferring fuel as it was too much for the system. Then, I started thinking maybe my vents would be clogged.

The crossover is direct from tank to tank.
Mike_M is offline   Reply With Quote
Old 09-19-2020, 03:47 PM   #14
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by Comodave View Post
I have never opened the crossover valve on my boat. Port engine and genset run on port tank and starboard engine runs on starboard tank only. Returns go to tank supplying the engine.
I'm not a fan either but I'm thinking that I may be able to fill both tanks from one side if the fuel dock doesn't have dual pumps available. I guess these were plumbed when the boat was built in the event somebody were to be on the hook and using a lot of fuel for the Jenny and the stability issue
Mike_M is offline   Reply With Quote
Old 09-19-2020, 04:01 PM   #15
Guru
 
Giggitoni's Avatar
 
City: Vallejo, California
Country: United States
Vessel Name: Mahalo Moi
Vessel Model: 1986 Grand Banks 42 Classic
Join Date: Jun 2008
Posts: 1,943
Quote:
Originally Posted by Redhook98 View Post
Are your fuel tank vents working correctly? Next time try it with your fuel caps off your tanks.
I think this ^ should be the next thing to investigate. Look for mud wasps within an inch or two from your tank vent openings on the side of your hull. Next time youíre out, as Redhook suggests, leave your fuel caps off (maximum tank venting) and run the rpm up to cruise setting.
__________________
Ray
"Mahalo Moi"
1986 GB-42 Classic
ΜΟΛΩΝ ΛΑβΕ
Giggitoni is offline   Reply With Quote
Old 09-19-2020, 04:28 PM   #16
Guru
 
Soo-Valley's Avatar
 
City: Gulf Islands
Country: canada
Vessel Name: Soo Valley
Vessel Model: Grand Banks 36
Join Date: Jul 2019
Posts: 1,325
Quote:
Originally Posted by Mike_M View Post
Thanks so much for all of the responses .

What's interesting is, I can have the boat idle for 30 minutes plus with the Genny running and then put a load and she starves out. Would you suspect that my vents may be clogged? at idle, it's not drawing as much fuel but if the vents are clogged maybe it's too much for my system when under load.

Also, would there be any harm in closing both crossover valves as I have the port open and the starboard shut and she runs fine. I left it this way as I loss both engines in 12 foot seas. At that time, I just closed the starboard cross-over valve and re-primed the mains as it was quite the Panic moment. My initial thought was, I could not have all three systems pulling from the tanks and also transferring fuel as it was too much for the system. Then, I started thinking maybe my vents would be clogged.

The crossover is direct from tank to tank.
Then the cross over is not causing your problems, IMO. Edit: You have the starboard cross over shut and port open should only affect the the crossover, not fuel to engines! I thought you closed the fuel in to manifold from starboard.

Original problem was you had to close the starboard feed and prime to restart and then both engines ran with only port feed.

You now say both engines and genny idle for 30 minutes and then starve when put under load. Is this with only the port open?

Or is from the original post with both starboard and port open?
__________________
SteveK
You only need one working engine.
That is why I have two.
Soo-Valley is offline   Reply With Quote
Old 09-19-2020, 04:31 PM   #17
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by Giggitoni View Post
I think this ^ should be the next thing to investigate. Look for mud wasps within an inch or two from your tank vent openings on the side of your hull. Next time youíre out, as Redhook suggests, leave your fuel caps off (maximum tank venting) and run the rpm up to cruise setting.
Agree, that is at the top of the checklist. What's weird is when I close the starboard cross-over valve, the boat runs great. I guess the additional transfer of fuel is the hinging point for the lack of ventilation
Mike_M is offline   Reply With Quote
Old 09-19-2020, 04:33 PM   #18
Veteran Member
 
Mike_M's Avatar
 
City: Suttons Bay, MI
Country: USA
Vessel Name: Sand Dollar
Vessel Model: Jefferson 45
Join Date: Mar 2017
Posts: 38
Quote:
Originally Posted by Soo-Valley View Post
Then the cross over is not causing your problems, IMO.

Original problem was you had to close the starboard feed and prime to restart and then both engines ran with only port feed.

You now say both engines and genny idle for 30 minutes and then starve when put under load. Is this with only the port open?

Or is from the original post with both starboard and port open?
Sorry for the confusion... the port crossover is open and with the starboard crossover closed, the boat runs fine. If I open both crossover valves so that the tanks balance out, it starves under load.
Mike_M is offline   Reply With Quote
Old 09-19-2020, 04:37 PM   #19
Guru
 
Soo-Valley's Avatar
 
City: Gulf Islands
Country: canada
Vessel Name: Soo Valley
Vessel Model: Grand Banks 36
Join Date: Jul 2019
Posts: 1,325
Quote:
Originally Posted by Mike_M View Post
Sorry for the confusion... the port crossover is open and with the starboard crossover closed, the boat runs fine. If I open both crossover valves so that the tanks balance out, it starves under load.
No worries. More confused now. A direct line crossover from tank to tank should not be causing the problems you have described whether one or both taps are open or closed. All the crossover does is level the fuel.
__________________
SteveK
You only need one working engine.
That is why I have two.
Soo-Valley is offline   Reply With Quote
Old 09-19-2020, 05:16 PM   #20
Guru
 
City: Boston
Country: US
Vessel Name: Adelante
Vessel Model: IG 30
Join Date: Nov 2016
Posts: 991
Crossovers are not essential. Mine is closed.
In addition to a vent check, I would inspect all of the copper fuel tubing. If one line has a kink, it could restrict fuel flow. (Although that doesn't explain all engine scenario)
__________________

SoWhat 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





All times are GMT -5. The time now is 05:04 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
×