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
> Front fuel filter, Couldn’t we do better than burying the filter under the tank?
worn
post Nov 25 2024, 06:33 PM
Post #1


can't remember
****

Group: Members
Posts: 3,355
Joined: 3-June 11
From: Madison, WI
Member No.: 13,152
Region Association: Upper MidWest



Getting closer and closer to the all new for 1976 2056 starting extravaganza. No fuel pressure cause I kinked a hose. Sure, I may not need 75’ of hose slack under the tank. Remedied that only to find fuel weeping from a new fuel filter. I am getting used to pulling the tank but it seems like a supposedly serviceable filter might be placed in a more prominent spot. Like above the tank, seen from the frunk. Or like maybe at the beginning of the fuel delivery loop in the engine bay. Or even where it used to be under the car. Why is stock the best possible world? Don’t get me wrong, I love stock.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
jim_hoyland
post Nov 25 2024, 06:40 PM
Post #2


Get that VIN ?
*****

Group: Members
Posts: 9,532
Joined: 1-May 03
From: Sunset Beach, CA
Member No.: 643
Region Association: Southern California



I moved the filter and pump into the front trunk . Added a ball valve to shut off fuel during filter changes. Also added a fuel pressure gauge and covered the entire assembly with a removable lexan cover.


Attached thumbnail(s)
Attached Image
User is online!Profile CardPM
Go to the top of the page
+Quote Post
Ishley
post Nov 25 2024, 07:07 PM
Post #3


Member
**

Group: Members
Posts: 167
Joined: 4-October 21
From: Clarendon Hills Il
Member No.: 25,957
Region Association: Upper MidWest



I moved my fuel pump to the 76 location. I left the fuel filter in the rear in the original 72 location below the battery. Many will say that the filter should be ahead of the fuel pump…but every BMW I’ve ever owned has the fuel pump in the tank and a filter down stream. I think most modern cars have it that way.

I thought on the late cars, you pull the pump out (in the frunk) and the filter is behind it in a fitting. You could reach it without disturbing the tank.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
hndyhrr
post Nov 25 2024, 08:19 PM
Post #4


Senior Member
***

Group: Members
Posts: 586
Joined: 1-September 13
From: central point,oregon
Member No.: 16,332
Region Association: Pacific Northwest



I moved the fuel pump to under the tank and the filter is up under by the steering rack so I don't have to pull tank to change the filter. Pumpkin is a 70 1.7
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bkrantz
post Nov 25 2024, 09:02 PM
Post #5


914 Guru
*****

Group: Members
Posts: 8,154
Joined: 3-August 19
From: SW Colorado
Member No.: 23,343
Region Association: Rocky Mountains



In theory, lots of excess line (hose) below the tank lets you extract and replace the filter via the 4" access hole, and then return the filter to a more protected environment. That's what I did when I moved my pump to the front. I suppose the filter could live by the steering rack, especially if carefully located and anchored in place. I don't like the idea of putting the filter (and pump) in the frunk, where leaking gas could pond and cause a REAL BIG disaster.

BTW, as most of us know, modern vehicles with pumps and "lifetime" filters that live in gas tanks are a b*tch to replace, sometimes requiring dropping the tank, so a 914 set up that way would not be that different.

(When I changed the pump in my Suburban I decided to cut an access hole in the cabin floor under the middle row seat instead of dropping the tank.)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
technicalninja
post Nov 25 2024, 09:16 PM
Post #6


Advanced Member
****

Group: Members
Posts: 2,014
Joined: 31-January 23
From: Granbury Texas
Member No.: 27,135
Region Association: Southwest Region



The placement of the filter decides the level of filtration in my book.

Pre-pump the filter is lower filtration level VS post pump.

Modern stuff has an in-tank "sock" that is ten times finer than the in-tank screen of a 914 and it replaces both the screen and the pre-pump filter.

Post pump for fuel injection is either a very fine filter (1960s-2005ish) or in modern stuff COMPLETELY left off...

More than 70% of cars built today have no secondary filter at all!

These cars all have plastic gas tanks that don't corrode, and the fuels today are many times cleaner than the fuels of the past.

Depending on tank condition I'd use both a pre and post filter on FI and a pre pump filter on carbs.
The pre-pump filter should be changed twice as often as the post.

Edit: On many late model trucks, it is possible to remove the bed mounting bolts on one side, loosen the other side up bigtime, and tilt the bed up to gain access.
A bit like a Grand Piano!
You can easily change a pump on a full tank of gas this way.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Jamie
post Nov 25 2024, 09:24 PM
Post #7


Senior Member
***

Group: Members
Posts: 1,074
Joined: 13-October 04
From: Georgetown,KY
Member No.: 2,939
Region Association: South East States



QUOTE(hndyhrr @ Nov 25 2024, 06:19 PM) *

I moved the fuel pump to under the tank and the filter is up under by the steering rack so I don't have to pull tank to change the filter. Pumpkin is a 70 1.7

I moved the pump and filter to the front above the steering rack cover, easy access. The sock in the tank is a useless extra maintenance item easily damaged, so external filters under tank placed before and after the pump is a much better alternative for access. (IMG:style_emoticons/default/aktion035.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
JamesM
post Nov 25 2024, 11:46 PM
Post #8


Senior Member
***

Group: Members
Posts: 1,997
Joined: 6-April 06
From: Kearns, UT
Member No.: 5,834
Region Association: Intermountain Region



QUOTE(Ishley @ Nov 25 2024, 06:07 PM) *

I moved my fuel pump to the 76 location. I left the fuel filter in the rear in the original 72 location below the battery. Many will say that the filter should be ahead of the fuel pump…but every BMW I’ve ever owned has the fuel pump in the tank and a filter down stream. I think most modern cars have it that way.

I thought on the late cars, you pull the pump out (in the frunk) and the filter is behind it in a fitting. You could reach it without disturbing the tank.



(IMG:style_emoticons/default/agree.gif) This

In my opinion the best pump/filter arrangement for 914s. Front mounted late style Bosch 2 port pump with NO fuel filter between the tank and the pump, just an adaptor in place of the stock filter to adapt the line size from the tank outlet to the pump inlet. Then post pump use a 5/16(8mm) in 5/16(8mm) out high pressure, decent sized (lager than stock), small micron filter.

Ideally do this using the late style front trunk fuel pump blister so you can have more or less a straight shot of fuel line from the tank outlet to the pump inlet, and then 180 the pressure side of the pump back to the tunnel line. No bends in the suction side of the line help keep it from collapsing.

Fun fact, this is what the VW factory eventually wound up doing as well in the mid 80s on the Vanagons that started out using the exact same pump and filter as the 75/76 914s to help with cavitation and noisy pump issues. The type 4 and early WBX Vanagons through about 84 used the same setup as the late 914s. Around 85 they replaced the pre pump filter with a barbed adaptor and used a larger post pump filter. then in the final years they just made the outlet on the tank larger to eliminate the adaptor.

Given the Vanagon tanks had no screen or pre filter I don't have any concerns that design of pump can handle it. I look at it as the way the factory would have evolved the 914 had it stayed in production.

I do like keeping the filter out of the engine bay though just to have less fuel volume to potentially boil back there.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Craigers17
post Nov 26 2024, 04:21 AM
Post #9


Senior Member
***

Group: Members
Posts: 806
Joined: 5-August 17
From: Rome, GA
Member No.: 21,317
Region Association: South East States



Many folks will hate this setup for various reasons, but I moved my setup to the frunk mainly for ease of changing the filter/pump. I realize it's not pretty / hidden, but it is very easy to access and now I can change the filter in just a few minutes with virtually zero fuel spillage. I know......paint job is in need of love.


Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
slivel
post Nov 26 2024, 11:23 AM
Post #10


Old car....... older driver
***

Group: Members
Posts: 515
Joined: 10-July 04
From: San Diego
Member No.: 2,332
Region Association: Southern California



QUOTE(jim_hoyland @ Nov 25 2024, 04:40 PM) *

I moved the filter and pump into the front trunk . Added a ball valve to shut off fuel during filter changes. Also added a fuel pressure gauge and covered the entire assembly with a removable lexan cover.


I recommend replacing those worm drive hose clamps with FI rated clamps. Not so critical on the input side but it looks like a worm drive clamp on the output side.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Geezer914
post Nov 26 2024, 03:51 PM
Post #11


Geezer914
***

Group: Members
Posts: 1,771
Joined: 18-March 09
From: Salem, NJ
Member No.: 10,179
Region Association: North East States



Munted my pump and filter under the steering rack. All I have to do is drop the steering rack pan to change the filter or service the pump.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rjames
post Nov 26 2024, 03:58 PM
Post #12


I'm made of metal
****

Group: Members
Posts: 4,145
Joined: 24-July 05
From: Shoreline, WA
Member No.: 4,467
Region Association: Pacific Northwest



QUOTE(jim_hoyland @ Nov 25 2024, 04:40 PM) *

I moved the filter and pump into the front trunk . Added a ball valve to shut off fuel during filter changes. Also added a fuel pressure gauge and covered the entire assembly with a removable lexan cover.


@jim_hoyland , I can't tell from the picture. Is your pump mounted to the sheet metal, or just lying 'loose'? If loose, I'd recommend fastening it to the sheet metal using the late style clamp and rubber dampeners.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rfinegan
post Nov 26 2024, 05:03 PM
Post #13


Senior Member
***

Group: Members
Posts: 1,027
Joined: 8-February 13
From: NC
Member No.: 15,499
Region Association: MidAtlantic Region



I have been thinking of using a 81 Lincoln 5.0 spin on fuel filter where the 73 fuel pump would go and keep the 75 pump and pre- filter under the tank. It has got a cover and all too. Would make nice transition from the tangerine lines to the engine bay lines. Looks like a smaller spin on oil filter.Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Justinp71
post Nov 26 2024, 05:33 PM
Post #14


Senior Member
***

Group: Members
Posts: 1,605
Joined: 11-October 04
From: Sacramento, CA
Member No.: 2,922
Region Association: None



QUOTE(slivel @ Nov 26 2024, 09:23 AM) *

QUOTE(jim_hoyland @ Nov 25 2024, 04:40 PM) *

I moved the filter and pump into the front trunk . Added a ball valve to shut off fuel during filter changes. Also added a fuel pressure gauge and covered the entire assembly with a removable lexan cover.


I recommend replacing those worm drive hose clamps with FI rated clamps. Not so critical on the input side but it looks like a worm drive clamp on the output side.



Good call, I was going to say the same thing. The wormdrive clamps get distorted and do not clamp evenly, only rated for lower pressure systems. Even more important in the engine bay, there was a member here that burned down his car from a ruptured fuel line in the engine bay.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Justinp71
post Nov 26 2024, 05:39 PM
Post #15


Senior Member
***

Group: Members
Posts: 1,605
Joined: 11-October 04
From: Sacramento, CA
Member No.: 2,922
Region Association: None



Could you move the filter to the engine bay? In a diagram I got from Clewett for an EFI system they had the filter after the pump. The clearances are large in the pump I believe they can most likely handle small particles.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
3 User(s) are reading this topic (3 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 30th November 2024 - 09:53 PM