Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
 Reply to this topicStart new topic
> Fuel flow Question from a rookie, What should I expect?
jack20
post Apr 19 2015, 03:50 PM
Post #1


Member
**

Group: Members
Posts: 406
Joined: 7-November 14
From: Granite Bay, CA
Member No.: 18,099
Region Association: Northern California
If I disconnect the fuel line forward of the fuel pump, what kind of flow should I be seeing from the tank. The tank has about 3 gal of fuel.
Thanks,
Jack
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Mike Bellis
post Apr 19 2015, 03:57 PM
Post #2


Resident Electrician
*****

Group: Members
Posts: 8,345
Joined: 22-June 09
From: Midlothian TX
Member No.: 10,496
Region Association: None
steady until empty... (IMG:style_emoticons/default/biggrin.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
pilothyer
post Apr 19 2015, 04:01 PM
Post #3


Member
***

Group: Members
Posts: 838
Joined: 21-May 08
From: N. Alabama
Member No.: 9,080
Region Association: South East States
If you mean disconnect the line from the pump on it's outlet port, you probably wouldn't see much flow, very little if any. On the other hand if you disconnect the line from the inlet port you will gravity flow the tank until empty.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
TheCabinetmaker
post Apr 19 2015, 04:07 PM
Post #4


I drive my car everyday
*****

Group: Members
Posts: 8,300
Joined: 8-May 03
From: Tulsa, Ok.
Member No.: 666
I'd guess you'll lose about three gallons.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
jack20
post Apr 19 2015, 06:40 PM
Post #5


Member
**

Group: Members
Posts: 406
Joined: 7-November 14
From: Granite Bay, CA
Member No.: 18,099
Region Association: Northern California
Thanks guys. I meant fuel filter not fuel pump. If I disconnect the line from the inlet side what should I expect in the way of flow. Sorry.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
somd914
post Apr 19 2015, 07:28 PM
Post #6


Member
***

Group: Members
Posts: 1,171
Joined: 21-February 11
From: Southern Maryland
Member No.: 12,741
Region Association: MidAtlantic Region
Carbs or FI?

With D-Jet (can't speak for L-Jet) pump will come on for a few seconds when the ignition is switched on but then shut off until you start the engine. Pressure should be around 30 PSI if I recall correctly.

As for carbs, mine is wired such that the fuel pump comes on with the ignition and remains on, pressure is 3 PSI.

I'm not sure if I'm on the right track for what you are asking, but it appears that you don't have flow out of the pump before the filter, is that correct? If that is the case, do you ever hear the pump come on?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
worn
post Apr 19 2015, 07:50 PM
Post #7


can't remember
****

Group: Members
Posts: 3,156
Joined: 3-June 11
From: Madison, WI
Member No.: 13,152
Region Association: Upper MidWest
QUOTE(jack20 @ Apr 19 2015, 04:40 PM) *

Thanks guys. I meant fuel filter not fuel pump. If I disconnect the line from the inlet side what should I expect in the way of flow. Sorry.

You are trying to measure pump output eh? I would have to look it up, but it would be as described already. The stock FI would turn the pump on briefly. If you trick the pump relay, then you should be seeing a pretty steady stream. Tell us more. Even if I am an idiot the others in the bunch will have the answers.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
pilothyer
post Apr 19 2015, 08:58 PM
Post #8


Member
***

Group: Members
Posts: 838
Joined: 21-May 08
From: N. Alabama
Member No.: 9,080
Region Association: South East States
QUOTE(jack20 @ Apr 19 2015, 07:40 PM) *

Thanks guys. I meant fuel filter not fuel pump. If I disconnect the line from the inlet side what should I expect in the way of flow. Sorry.


If the sock in the tank isn't clogged you could expect free flow from the tank to the ground (IMG:style_emoticons/default/biggrin.gif) If you are trying to change the filter just squeeze off the line before you disconnect.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
jack20
post Apr 20 2015, 12:34 AM
Post #9


Member
**

Group: Members
Posts: 406
Joined: 7-November 14
From: Granite Bay, CA
Member No.: 18,099
Region Association: Northern California
My car is a project that is very close to drivable. A week or so ago I changed the fuel hoses under the tank because I was in there anyway. Today I tried to start the car for the first time in weeks. Started OK before. Today it would chug a bit but not run. I checked fuel flo at the filter inlet. Very weak. I pulled up the tank an the hoses I installed fely very flimsy and prone to kinking. I bought these at bird thinking they were what I needed. That's why I'm asking about flow to the filter.
1974 2.0 FI
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
euro911
post Apr 20 2015, 12:53 AM
Post #10


Retired & living the dream. God help me if I wake up!
*****

Group: Members
Posts: 8,849
Joined: 2-December 06
From: So.Cal. & No.AZ (USA)
Member No.: 7,300
Region Association: Southern California
I'd pull the tank again and check the internal filter (sock). It's quite possible that it's clogged with varnish.

Carefully remove and clean it or replace it if it's not in good shape.

Be careful with the fiber washers too.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
TheCabinetmaker
post Apr 20 2015, 04:28 AM
Post #11


I drive my car everyday
*****

Group: Members
Posts: 8,300
Joined: 8-May 03
From: Tulsa, Ok.
Member No.: 666
Sounds like you switched the lines at the tank.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bdstone914
post Apr 20 2015, 04:35 AM
Post #12


bdstone914
****

Group: Members
Posts: 4,522
Joined: 8-November 03
From: Riverside CA
Member No.: 1,319
QUOTE(The Cabinetmaker @ Apr 20 2015, 03:28 AM) *

Sounds like you switched the lines at the tank.



Hard to switch with them being different sizes. Making the hoses too long under the tank makes them prone to kinking. Look at them through the inspection hole under the tank and see if they are kinked.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
jack20
post Apr 21 2015, 12:01 AM
Post #13


Member
**

Group: Members
Posts: 406
Joined: 7-November 14
From: Granite Bay, CA
Member No.: 18,099
Region Association: Northern California
Thanks for all the help. Turns out that the fuel lines I ordered were too flexible and cut off the fuel flow, which I what I suspected. I went to the FLAPS and got some overkill hoses and that solved the flow problem. Back on the road after six months of work. Feels great!
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
« Next Oldest · 914World Garage · Next Newest »
 

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 

Display Mode: Standard · Switch to: Linear+ · Switch to: Outline

Track this topic · Email this topic · Print this topic · Subscribe to this forum

- Lo-Fi Version Time is now: 17th May 2024 - 09:31 PM
Invision Power Board v9.1.4 © 2024  IPS, Inc.
All rights reserved 914World.com © since 2002
914World.com is the fastest growing online 914 community!
We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ...