XJ6 & XJ12 Series I, II & III 1968-1992
Sponsored by:
Sponsored by:

Su fuel pump replacements?

  #1  
Old 02-25-2017, 09:20 AM
jjd's Avatar
jjd
jjd is offline
Senior Member
Thread Starter
Join Date: Oct 2010
Location: ireland
Posts: 290
Received 33 Likes on 28 Posts
Default Su fuel pump replacements?

Basically I'm fed up messing with points and fiddly wiring so can anyone recommend a modern replacement Electric fuel pump for the twins in the boot/ trunk?
 
  #2  
Old 02-25-2017, 03:56 PM
Jose's Avatar
Veteran Member
Join Date: Mar 2007
Location: Florida
Posts: 8,600
Received 2,425 Likes on 1,826 Posts
Default

for what car ?
 
  #3  
Old 02-26-2017, 09:47 AM
JagCad's Avatar
Veteran Member
Join Date: Jul 2012
Location: Walnut Creek, California
Posts: 6,796
Received 2,399 Likes on 1,880 Posts
Default

I think it is a carb car with one pump in each tank?


I'll withhold any thoughts pending confirmation or other.


Carl
 
  #4  
Old 02-26-2017, 12:21 PM
Doug's Avatar
Veteran Member
Join Date: Mar 2008
Location: Pacific Northwest USA
Posts: 24,736
Received 10,741 Likes on 7,097 Posts
Default

An SU pump with points definitely sounds like we're talking about an older car with carbs. Not fuel injection.

SU now makes replacement pumps with solid state circuits....no points at all! Yay! Not cheap, though. $200 each, I think?

However, I would think that any number of universal-type electric pumps would fill the bill, perhaps with some minor fiddling with connectors, nipples, etc to make a sanitary installation. You'd probably want a pump that maxes out at 5 psi pressure or so....typical pressure for carburetors. Probably $40 each or so?

Cheers
DD
 
  #5  
Old 02-26-2017, 01:19 PM
Jose's Avatar
Veteran Member
Join Date: Mar 2007
Location: Florida
Posts: 8,600
Received 2,425 Likes on 1,826 Posts
Default

by the way, I found a new Bosch 4FP pump for my XJ-6 in eBay UK, they are still making them. $63.00 delivered.

I also learned that the o.e.m. Lucas 4FP used in Series 3 XJ is a re-labeled Bosch 4FP pump.

The seller I ordered from has other types of fuel pumps, I'm thinking of replacing the annoying SU pumps in my S type with solid state pumps too, getting tired of them too.

if 5 psi is about what's needed, then I know what to look for. Redoing the hose connections / eliminating the banjo fittings is no big deal.
 
The following users liked this post:
Doug (02-26-2017)
  #6  
Old 02-26-2017, 02:07 PM
Doug's Avatar
Veteran Member
Join Date: Mar 2008
Location: Pacific Northwest USA
Posts: 24,736
Received 10,741 Likes on 7,097 Posts
Default

Originally Posted by Jose

if 5 psi is about what's needed, then I know what to look for. Redoing the hose connections / eliminating the banjo fittings is no big deal.

You can and probably should clarify the pressure needs and limitations with SU carbs....but 5 psi is a rule of thumb with carbureted cars in general

Cheers
DD
 
The following users liked this post:
Jose (02-27-2017)
  #7  
Old 02-26-2017, 02:40 PM
yarpos's Avatar
Veteran Member
Join Date: Jun 2014
Location: Alexandra, VIC, AU
Posts: 5,416
Received 2,086 Likes on 1,261 Posts
Default

Lower the better with SUs, the float bowl needle and seat isnt very strong. Maybe thats the wrong words, perhaps designed with lower pressures in mind.

Nominally the SU pumps are usually below 5psi, but that seems a good guideline. I am currently running one of those generic Facet electric fuel pumps on an old Morris with an SU. Its rated 3-5psi and works fine. I plan to replace it with a Pierburg pump like I have on my Jag but that is just due to my doubts about the longevity of the very cheap Facet pump.
 
The following 2 users liked this post by yarpos:
Doug (02-26-2017), Jose (02-27-2017)
  #8  
Old 02-27-2017, 09:08 AM
Jose's Avatar
Veteran Member
Join Date: Mar 2007
Location: Florida
Posts: 8,600
Received 2,425 Likes on 1,826 Posts
Default

ok ok, 3 to 5 psi. Are there pumps with ADJUSTABLE PSI ??
 
  #9  
Old 02-27-2017, 09:33 AM
JagCad's Avatar
Veteran Member
Join Date: Jul 2012
Location: Walnut Creek, California
Posts: 6,796
Received 2,399 Likes on 1,880 Posts
Default

Not that I am aware of. But, at least at one time, inline adjustment devices existed.


Older flat head Ford V8 carbs would flood easily. The original mechanical pump was well matched as to PSI's. But, after market electric pumps usually too much.


I used an electric pump and an adjustable valve on my "Hot Rod of the Forties" project. worked fine. Three 94's too much carb. Two didn't look as impressive but ran
better. My initial linkage opened all barrels at once. My progressive linkage under development, never got on the car.


Carl
 
The following users liked this post:
Jose (02-27-2017)
  #10  
Old 02-27-2017, 10:20 AM
Jose's Avatar
Veteran Member
Join Date: Mar 2007
Location: Florida
Posts: 8,600
Received 2,425 Likes on 1,826 Posts
Default

look what I got in the mail from UK today

replacement for Lucas 4FP fuel pump, the original was starting to sing the blues, the whinning became annoying. Why do they start whinning and humming?

looks identical to the old Lucas pump, first time I have to replace it since I bought the car, can't complain, I'll let you know if it works.
 
Attached Thumbnails Su fuel pump replacements?-new-fuel-pump-xj6.jpg   Su fuel pump replacements?-old-new-fuel-pumps-xj6.jpg  

Last edited by Jose; 02-27-2017 at 10:22 AM.
  #11  
Old 02-27-2017, 11:20 AM
Jose's Avatar
Veteran Member
Join Date: Mar 2007
Location: Florida
Posts: 8,600
Received 2,425 Likes on 1,826 Posts
Default

well darn it, I just installed the new pump, started the engine and it is making a horrible and intermittent noise, as if the insides were rubbing against something.

what could it be?
 
  #12  
Old 03-02-2017, 04:07 PM
jjd's Avatar
jjd
jjd is offline
Senior Member
Thread Starter
Join Date: Oct 2010
Location: ireland
Posts: 290
Received 33 Likes on 28 Posts
Default

Thanks for the info everybody....armed with this I'll search around for a replacement pump and report progress when I get sorted. Cheers again...
 

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread

All times are GMT -5. The time now is 02:03 AM.