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Posted by: maddhatter Jul 5 2011, 11:20 AM

I recently picked up a 73 1.7 that had been stored inside for 20 years. The body is great as expected sitting inside, but the fuel pump does not work among other things and looking for a replacement I see that they are no longer made. Great! Can I retrofit a later model pump to fit my car? I thought the injection systems were pretty much the same all the way through the years, but the newer pumps look vastly different from my hunk of metal pump, mine having 3 hose connections and the newer ones only the typical two. Thanks in advance.

Posted by: windforfun Jul 5 2011, 11:24 AM

AA has the old style for sale.

Posted by: vsg914 Jul 5 2011, 11:58 AM

New early model pumps are available, but run about 300 bucks. You can use the late (75/76) pump. its about 175. Or, you can a get a bosch pump from napa, part #N69133 for around 30 bucks. Its the identical pump used by the late model cars.

Posted by: vsg914 Jul 5 2011, 11:59 AM

BTW, Welcome to the World.

Posted by: Cap'n Krusty Jul 5 2011, 12:07 PM

When you get the late style pump (and I would), you're gonna need some 12mm fuel hose and a late type fuel filter. Once the stuff in hand, ask for instructions and we'll help you. Wouldn't hurt to buy the special hose from the fuel line to the filter (914 356 525 00), and about 15 ft of new 7mm FI hose and the required correct hose clamps.

The Cap'n

Posted by: Crash207 Jul 5 2011, 12:17 PM

Had the same issue on mine. Whacked it a few times and the pump started working again. Im sure it will need to be replaced but its working fine now.

Posted by: maddhatter Jul 5 2011, 12:44 PM

Thanks for the great responses here as I didn't realize this board was this active. Napa has the Bosch pump you recommend and I can get the 12 mm fuel line and filter there as well. How many feet of line am I going to need? Also, I am wondering if I should pull the gas tank to empty it completely, or just pump it out and refill it a few times to get all the old gas out as its not alot of fun pulling the gas tank out.

Posted by: jcd914 Jul 5 2011, 12:59 PM

Look in the tank for rust and when you find rust pull the tank and get it cleaned and coated.

Jim

Posted by: 76-914 Jul 5 2011, 04:06 PM

GPR & Pelican Parts both have the 7mm line. IIRC, NAPA did not have the High Pressure varient that we require. You'll need the Porsche style clamps anyway so order from one of those mentioned earlier. What the Cap't didn't tell you is this: when you get those parts and come back here for info, we're also going to have you relocate your fuel pump to the front. So yank the tank and find a vatter. But wait! There's more!! Then we're gonna have you replace the fuel lines in the tunnel. At which time some smart ass (and we have several) will mention that this is easier to do when the engine is out. Well if the engine is out, isn't this just the perfect opportunity to rebuild the tranny. And what self respecting (besides me) teener would rebuild a tranny with out a changing out their clutch. And if the tranny is out of the way then you must change over to 5 lug. Which will require a new set of bearings, also. About this time, one of Eric Shea's ads is going to wink at you and here comes UPS with your new calipers and slotted rotors. Furthermore, no 1.7 is worthy of PMB's performance package so I'd like to introduce you to Mr. Raby. Jake won't even speak to you unless you have your CC in hand and plan to be alive in the next year or so because that's how long the wait is. It is now 2 yr's later and what's left of the car you drove home is either in box's, a rust heap out back or at the painters. Jake called last week to say the engine is on the way and you just met Ron (Slits) who has convinced you that you need to buy the Shalom from him, pull the 6 out, install it in your car and then burn the Shalom.
To quote Scotty, "It's the right thing to do".

Posted by: jaxdream Jul 5 2011, 04:56 PM

Pull the tank and clean it out . Don't run the old stuff through your new pump, just empty it into another container and dispose of. Clean and inspec the tank for rust and such crud.Good luck...

Jack

Posted by: Cap'n Krusty Jul 5 2011, 05:10 PM

Some folks might tell you to move the pump, but I won't be one of them. Too much plumbing and adapting, and (unless you pop for SS pipes) you'll be pressurizing lines that were designed to run at no pressure at all. Keeping the pump in the back means you'll need maybe a foot or 18" of 12mm hose, the adapter hose, the pump, and new rubber fuel lines from the pump area to the engine area.

IME, the stuff you read about vapor lock is hearsay and mostly unsupported by evidence. I live where it gets hot, and I used to live in La La Land, where it's hot AND there's a lot of slow traffic, and I've never seen a single case of it.

Drain the tank, remove the filler neck and take a good look at the inside of the tank. If there's rust and/or crap in there, pull the tank, replace the hoses under there (some 7mm, some 9mm), and have the tank cleaned and coated. Be REALLY careful not to crimp the hoses when you reinstall everything. Get a new filter sock for the inside of the tank, too. Save the paper washers for the bottom fittings, they're hard to come by.

The Cap'n

Posted by: 914_teener Jul 5 2011, 05:22 PM

I am with the Cap'n on this one. I live in LA LA since I've had my teener. I retrofitted the three port pump to the two port pump ...bus part No. I believe, and installed it in the stock location. I have never had a problem with vapor lock or any other heat related problem.

I agree with not pressurizing the inlet line as they were not designed for it in your year. I have a '73 as well.

Issues will be:
The stock mounting clamp won't tighten on the smaller pump.

Other than that I would do what everyone has suggested and I really don't think it is necessary to move the pump up front. Save your energy for other things.....and there will be.

Good idea to dump the old fuel and inspect every fuel line while you are there. I ended up replacing ALL my rubber fuel lines, I have D-jet injected car. I used the CARB rated lines for the reformulated fuels now on the market. The jury is out on wether these are better or not....I am not a purist by any means but these connections are CRITCICAL to keep your car from going up in smoke.

This board is great....lots of characters and helpful folks..

Posted by: SLITS Jul 5 2011, 05:40 PM

Kent,

I don't know where you got the info on the NAPA pump, but it puts out 42 psig and I forget the GPH, but the numbers are sufficient. Bosch Number on the pump is 0 580 464 109. Actually listed for a Ford, but other than the electrical connectors being different, it is no different than the '75 - '76 style pump for $175.

And that is the Schlitzalom.

Found the info:

Part Number: BSH N69133
Product Line: Bosch

Fuel Pump Fitting Size[s] : Electric Fuel Pump
Fuel Pump Gallons Per Hour : 22.45
Fuel Pump Pressure Rating : 45 PSI

Posted by: maddhatter Jul 5 2011, 06:11 PM

More great info guys, thanks again. I will drain the tank and take a look see inside and see how bad it looks before I start yanking it out. I have had many other Porches before and thought it was time to get the complete Porsche experience and get a 914. We will see how these 914's compare to the other models for sheer fun....only wish it was a 2.0 though to make it a fair comparison!

Posted by: 76-914 Jul 5 2011, 06:22 PM

Not the Fuel pump. I was talking about the metric sized fuel hose that is rated for 50psi.IIRC they only carried carb rated metric hose. As far as that pump goes, I'm getting me one at that price.

Posted by: SLITS Jul 5 2011, 06:23 PM

Found the info and edited it above. Sorry Kent.

Part Number: BSH N69133
Product Line: Bosch

Fuel Pump Fitting Size[s] : Electric Fuel Pump
Fuel Pump Gallons Per Hour : 22.45
Fuel Pump Pressure Rating : 45 PSI

Posted by: Prospectfarms Jul 5 2011, 07:54 PM

Returning to the OP, you can place your old pump in a bucket of diesel fuel, reverse the polarity from leads attached to a 12 volt battery and watch all the crud blow out.
I did that and it worked for a couple of months. When it failed again, I meticulously checked every in-line pump from NAPA until I came across the $30 version with the correct flow and pressure:

http://www.914world.com/bbs2/index.php?s=&showtopic=131436&view=findpost&p=1494564

I installed it in its normal place in the engine compartment. Works perfectly.

Regarding the pump location: What's up with the vapor lock theory? Its conventional wisdom to relocate the pump to the front -- the stock position in the later models -- but Cap'n Krusty has some good points against it. I agree. The return flow to the tank from the engine means that the fuel pump is liquid cooled. After driving fast and slow at 93 degree ambient temp and 80 % humidity, a few days ago, the pump felt cool to the touch.

Regarding pulling the tank: I'm afraid you must unless the tank was carefully drained 20 years ago, and remains rust free today. Unlikely. If you don't pull it off and clean it out (then line it with Red-kote) it will remain a constant source of potential trouble.

Good luck.

Posted by: 76-914 Jul 5 2011, 08:40 PM

I cannot speak to the 914 vapor locking myself and I'm not going to argue with someone that does this for a living. I have experienced it in aircraft and other gasoline engines. Most notably the Chevy 327 w/ air. When you raised the hood on a Texas version it would have a bunch of wooden clothes pins on the steel fuel line to insulate it against the heat. Your kind of on track re: the cool fuel coming from the tank. Vapor lock is usually going to happen after the engine is shut down and the temps in and around the fuel pump are hot. Gas begins to boil and bubbles. When I ran auto gas in my plane I would close the fuel and run the engine till it died. When I restarted the cold gas would cool the pump and carb so vapor lock was denied. It is more prominent in April or May (I don't know when they do it here?) when the gasoline blends are altered.
So did it matter. I don't F'n know but I was changing out the plastic lines so it was a no brainer for me.

Posted by: SLITS Jul 5 2011, 09:41 PM

The factory moved the pump to the front for the vapor lock reason in '75 - '76. In very hot weather, or extremely hot climates a Porsche will vapor lock when running.

My /4 did it in Vegas & Laughlin, Nevada. Temps ranged from 98 - 105. It was pulling the long hill out of the Colorado River Valley.

My /6 did it climbing out of Laughlin to Kingman, AZ.

If you look at the location of the fuel pump from '69 - '74, you might notice that the exhaust of hot air from the HEs is directed at or very close to the fuel pump. It is my belief, unfounded, that this hot air, under extreme loads or heat, overheats the pump, boils n(ok Nerds, volatilizes) the gas in the pump and the pump doesn't really pump air (fumes) very well.

Moving it to the front is a bit of work but is not brain surgery. It eliminates a potential or real problem combined with proper center tunnel lines and fuel hose.

Your choice ... mine is from experience.

Posted by: Prospectfarms Jul 5 2011, 09:45 PM

That's good writing BTW, and interesting. I agree heat soak VL exists, experienced it with VW's. What I saw was gas boiling out of a carburetor, or probably more correct to say the fuel line to the carburetor. Would a pressurized FI system do that? I don't know. Just in case, when I installed the "non-stock" FP, I made a new bracket that dropped the pump a little bit. Not too much, maybe and inch, so it is separated from the (sometimes very hot) engine tin by that much.

"When I ran auto gas in my plane"

That sounds a little scary.

One thing I forgot to say to Madhatter that I'm surprised no one else mentioned is that a 914's have one of the easiest to remove gas tanks in history. It's one screw and two hose clamps.

Posted by: timofly Jul 6 2011, 07:55 PM

I wouldn't even think about arguing with people on here who have forgotten more than I know about 914s, but I moved my fuel pump up front because I had two pumps fail by leaking fuel all over the place. I just couldn't get comfortable with the idea of a leaky pump 6" from the HE.

I also went with the SS lines all the way down the tunnel and into the engine compartment. I've heard some say that the 35 year old plastic fish tank lines in the engine compartment are just fine, but I am not a born optimist, so those got replaced with real fuel lines too.

Just one man's opinion.

Posted by: SteveL Sep 30 2014, 12:15 PM

[/quote]

I am with the Cap'n on this one. I live in LA LA since I've had my teener. I retrofitted the three port pump to the two port pump ...bus part No. I believe, and installed it in the stock location. I have never had a problem with vapor lock or any other heat related problem.

I agree with not pressurizing the inlet line as they were not designed for it in your year. I have a '73 as well.

Issues will be:
The stock mounting clamp won't tighten on the smaller pump.

Other than that I would do what everyone has suggested and I really don't think it is necessary to move the pump up front. Save your energy for other things.....and there will be.

Good idea to dump the old fuel and inspect every fuel line while you are there. I ended up replacing ALL my rubber fuel lines, I have D-jet injected car. I used the CARB rated lines for the reformulated fuels now on the market. The jury is out on wether these are better or not....I am not a purist by any means but these connections are CRITCICAL to keep your car from going up in smoke.

This board is great....lots of characters and helpful folks..


[/quote]



I realize this is from a post about 3 years ago, but you said that you put a new 2 port fuel pump in the stock location. I am trying to do the exact same thing.
I used the clamp bracket from the 3 port with a wrap of cork gasket material around the new pump to make it tight. I put the bracket as close to the inlet end of the pump as possible. When I try to put the pump up on the studs, the 12mm inlet fuel line kinks because that end of the pump is too close to the firewall.
How did you get around this?

Posted by: Cap'n Krusty Sep 30 2014, 12:25 PM

I use enough hose to form a loop.

The Cap'n

Posted by: JawjaPorsche Sep 30 2014, 12:29 PM

I used the bracket that came with a Bosch coil.


Attached image(s)

Posted by: SteveL Sep 30 2014, 12:51 PM

In the picture above, the pump has been moved to the lower firewall. Can it be left in the stock location on the existing rubber mounts?
If you move it to the firewall, is it loud inside the cabin? Just drill a couple of holes in the firewall for a bracket?

Thanks

Posted by: RobW Sep 30 2014, 12:57 PM

You can try anything you want. The stock pump comes and goes the same side where the new pump passes from one side to the other. You also have the fuel filter. Plus the fuel pump isn't the easiest thing in the world to attach.

I did mine a few months ago just as pictured with excellent results.

Posted by: 914_teener Sep 30 2014, 02:11 PM

I did mine also as pictured above a while ago

Easy.....I've driven in 110 ambient temps in So Cal.

It was an easy install with no problems.