Home 
Home Search search Menu menu Not logged in - Login | Register
> Jensen Healey & Jensen GT Tech > Fuel Stuff > pressure relieve valve

 Moderated by: Greg Fletcher
New Topic Reply Printer Friendly
pressure relieve valve  Rating:  Rating
AuthorPost
 Posted: 03-31-2013 06:49 pm
  PM Quote Reply
1st Post
jdodds56
Member
 

Joined: 12-31-2012
Location: Escondido, California USA
Posts: 4
Status: 
Offline
I have read several topics on the fuel system/gas tanks and just get more confused. I hope somewhere out there is help.

I have a 1974 J-H. Manufactured in Dec 1973. Everything I have looked at shows the pressure relieve valve on top of the tank, and under it there are two connectors. My old tank, which was out of the car when I got it, only has one. Any J-H historians out there that can explain to me what was added to later J-H's that required two? I am having a tank made and want to know if I should have it made with two. If there is something I should be concerned about adding later to the fuel system.

Back To Top PM Quote Reply  

 Posted: 04-02-2013 03:19 pm
  PM Quote Reply
2nd Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
There is a return line from the fuel pump that prevents siphoning when the car is parked with the nose downhill. The other is the vent tube that connects to the carbon canister.
http://deltamotorsports.com/cgi-bin/bigimage.pl?site+DMSCAT+img+/products/Images/FuelSystemPlate.gif

Back To Top PM Quote Reply

 Posted: 04-02-2013 03:58 pm
  PM Quote Reply
3rd Post
jdodds56
Member
 

Joined: 12-31-2012
Location: Escondido, California USA
Posts: 4
Status: 
Offline
Then I assume it would be wise of me to add the return line to prevent the siphoning. Thanks

Back To Top PM Quote Reply  

 Posted: 04-02-2013 06:47 pm
  PM Quote Reply
4th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
Please read Jody Kerr's excellent article on installing a fuel tank.
http://www.theymightberacing.com/Projects/FrameOff/JH74G/FuelSystem.aspx
There is a check valve in the return line that makes the seemingly impossible system work.

Back To Top PM Quote Reply

 Posted: 04-02-2013 10:28 pm
  PM Quote Reply
5th Post
Jim Ketcham
Member
 

Joined: 03-13-2005
Location: Salt Point, New York USA
Posts: 208
Status: 
Offline
Do not forget that there is a check valve in the anti-syphon line. Jensen placed it completely inside the hose so most got thrown out with the old hoses.

Back To Top PM Quote Reply  

 Posted: 04-03-2013 03:41 am
  PM Quote Reply
6th Post
jdodds56
Member
 

Joined: 12-31-2012
Location: Escondido, California USA
Posts: 4
Status: 
Offline
Seeing how I am manufacturing the anti-siphon connection as an after market part for my car, how does one go about finding the right size check valve?

Back To Top PM Quote Reply

 Posted: 04-03-2013 07:42 pm
  PM Quote Reply
7th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
The info is in the article at Jody Kerr's site. Basically it's a metal plug with a .046 hole drilled through it.

Back To Top PM Quote Reply  

 Posted: 04-03-2013 10:19 pm
  PM Quote Reply
8th Post
jdodds56
Member
 

Joined: 12-31-2012
Location: Escondido, California USA
Posts: 4
Status: 
Offline
Thank you the info. It makes sense to me now after all the reading. Can't wait to get the tank done and in. I'm sure I'll have more questions in the near future.

Back To Top PM Quote Reply

 Posted: 04-04-2013 01:02 am
  PM Quote Reply
9th Post
Jim Ketcham
Member
 

Joined: 03-13-2005
Location: Salt Point, New York USA
Posts: 208
Status: 
Offline
You can buy fuel check valves 1/4 or 5/16" on eBay or Amazon. The lines on both my cars had tiny check valves installed in the return lines. These are actual One way valves, not just an orifice as described in Jody Kerr's article. These were fairly common in many cars and are still available.

Back To Top PM Quote Reply  

Current time is 08:30 am  
> Jensen Healey & Jensen GT Tech > Fuel Stuff > pressure relieve valve Top




UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems