Take a look at my fuel pump

[Jameel]

While my engine is out I'm evaluating my fuel lines. Out back they look great, up front they look pretty good too. Soft, no cracks, no signs of leaks. However, my fuel pump is another story. It looks like someone pulled it from the bottom of a river. I've never had a problem with it in the last 7000 miles, and the PO didn't touch it either in 20,XXX miles.

The odd thing is, the terminals under the boots look like new. I wasn't expecting that.

So I'm leaning towards putting a new fuel pump in as a matter of course. It's not a huge expense, and seems like really good insurance. Of course I'm also leaning heavily towards redoing my tunnel lines too, since I think the short lines to the pump and tank should be replaced.

So couple questions. I've seen folks cut off the ferrule between the tunnel lines and replace just the short lines, using hose clamps to join up. Some people cry foul, but the short pickup section between the pump and the tank is held on by hose clamps. So what gives? Hose clamps are a no no to join to the tunnel lines, but okay for the pickup? Doesn't make sense.

Also, can someone identify the dark spot on the bottom of my tank? It looks wet, but its just really glossy. It's never leaked here while I've owned the car, and there's no evidence of a leak at the pickup tube. Any idea what this could be? Options?

[Walt Fricke]

I wouldn't use hose clamps on the pressure side lines from the fuel pump. the hose clamped section is only under gravity pressure, not the 5 or 6 bar (75-90 psi) you might see on the pressure side).

[DRACO A5OG]

Originally Posted by walt fricke

i wouldn't use hose clamps on the pressure side lines from the fuel pump. The hose clamped section is only under gravity pressure, not the 5 or 6 bar (75-90 psi) you might see on the pressure side).

+1

[juanbenae]

I might consider replacing the mounting clamp as well per the photos... you don't mention the year of the year of the car?? the SC CIS systems has the fuel pump at the tank like you show so the tunnel line(s) handle heavy pressures. the middies, 74-77 had the CIS pump in the motor compartment therefor the tunnel lines do not handle the high CIS fuel pressures. that being the case the middie cars fuel lines can be made to sample w/o the factory higher pressure 3.oL lines of the later SC models.

[Jameel]

Oh yeah, its a 1983 SC.

[Jameel]

Actually, I think someone messed with the fuel pump at some point, what with that one adjustable-style hose clamp there. I definitely will be replacing that too.

[Mark Salvetti]

My SC fuel pump looks much nicer, when I removed it I found 11/88 scratched into it. I parked the car in 1996, so this is after 8 years and I don't know how many miles.


It still works, but I decided to have it rebuilt by Fuel Injection Corporation rather than roll the dice on a new pump that is made in China now. They quoted $195 with a 1 or 2 year warranty, can't remember which.

BoxsterGT offers new front hoses that would be connected to the tunnel lines with clamps, since you can't undo the crimps that are there now. But I've decided to replace all the lines (front, tunnel, engine compartment) with his hoses. Costs about $500.

Mark

[Walt Fricke]

Juan - if your '75 came with the rear mounted fuel pump, then it was '76 that Porsche came to its senses and moved the pump back up front, where it had been in the 2.4s and at least some earlier models.

Or your car was an early production model, and didn't get switched over - I always thought it was only the '74 which had the fuel pump heating/vapor lock issues, at least when tracked.

[juanbenae]

Originally Posted by Walt Fricke

Juan - if your '75 came with the rear mounted fuel pump, then it was '76 that Porsche came to its senses and moved the pump back up front, where it had been in the 2.4s and at least some earlier models.

Or your car was an early production model, and didn't get switched over - I always thought it was only the '74 which had the fuel pump heating/vapor lock issues, at least when tracked.

correct as usual walt. per the docs I hold built in sept of 74 as a 75 model with fuel pump defiantly in the rear. motor compartment driver's side. maybe they moved them up later in the production of the 75 model?


my very early production 78SC had some oddities too having been built in sept of 77. passenger side mirror delete and chrome window trim & polished sunroof trim were a couple things I found after researching some of the 77-78 transition details.

[Jameel]

Originally Posted by Mark Salvetti

My SC fuel pump looks much nicer, when I removed it I found 11/88 scratched into it. I parked the car in 1996, so this is after 8 years and I don't know how many miles.


It still works, but I decided to have it rebuilt by Fuel Injection Corporation rather than roll the dice on a new pump that is made in China now. They quoted $195 with a 1 or 2 year warranty, can't remember which.

BoxsterGT offers new front hoses that would be connected to the tunnel lines with clamps, since you can't undo the crimps that are there now. But I've decided to replace all the lines (front, tunnel, engine compartment) with his hoses. Costs about $500.

Mark

Huh, so tell me more about rebuilding. I just ordered a new Bosch from our host, but if its made in China, maybe I should consider rebuilding mine? It does work after all, might not be much to look at, but inside it might be just fine.

[juanbenae]

you can't rebuild a fuel pump with regular arms, or even specifically t-rex arms. buy a new fuel pump & THE mount/clamp grasshopper... the clamp will not come with the pump, but if the rust is that prevalent on what we see the mount likely needs replacement too.

that appears to be a rusty mess... if you considered a rebuild spraying it with WD-40 & keep driving? id rebuild it, and see if I could get a spare to keep in the trunk..

[porsche930dude]

I bet the tank would leak if you peeled off the undercoating there. Water sinks in gas. If it sat undriven for a long time it can rust at the bottom. Pin holes could be brazed up. But I wouldnt touch it until it gets worse

[sugarwood]

Originally Posted by Mark Salvetti

It still works, but I decided to have it rebuilt by Fuel Injection Corporation rather than roll the dice on a new pump that is made in China now. They quoted $195 with a 1 or 2 year warranty, can't remember which.

Mark

Is there any merit to this?
Making a fuel pump is not rocket science.
You can get a new Bosch for about $100 at FCP, half the cost of your rebuild.
Millions of cars use Bosch fuel pumps with no issues.

[sugarwood]

You can replace a fuel pump without lifting the gas tank, right?
You just remove that skid plate thing (...which is a total nightmare to reinstall)

Does the entire gas tank drain when you remove the pump?
Do you just plug up the holes while swapping as fast as you can?

[Bill Douglas]

Fuel pump failures cause quite a large percentage of breakdowns on the road. And that is one of the ugliest I've seen. Just swap out the fuel pump and the fuel filter and your life will be a happier place.

My fuel pump failed along a motorway without a breakdown lane. Man, that was scary waiting for a tow truck. I won't go through that again for the sake of a fuel pump.

[Mark Salvetti]

Originally Posted by sugarwood

Is there any merit to this?
Making a fuel pump is not rocket science.
You can get a new Bosch for about $100 at FCP, half the cost of your rebuild.
Millions of cars use Bosch fuel pumps with no issues.

Can you find a new Bosch that cheap? Pelican's price is $185 for my SC, FCP on sale for $140. It just seems like the new Bosch pumps don't have the greatest reputations. Not as bad as the coils, but reading threads here it does seem like they have issues. They may not be made in China, maybe the Czech Republic.

Fuel Injection Corp told me they do get a fair number of returns on the new pumps. I'd rather spend a bit more and have higher confidence in the pump. Having one fail is such a hassle, between getting towed and probably having to drain the tank, I would rather the piece of mind.

Mark

[sugarwood]

That honestly sounds like internet hype cycle.

One guy with a bad pump posts a thread, thousands of people read it,
it gets replicated dozens of times across lots of car forums,
and next thing you know, people are rebuilding fuel pumps, instead of buying new ones.

[Mark Salvetti]

Yeah, I know. I considered that. Still not sure which way to go, the pricing is pretty close. Maybe I'm putting too much stock on what Fuel Injection Corp told me, they probably make more money on the rebuilds, but at some point you have to trust somebody.

I wonder if John Walker or Steve Weiner have seen problems with new pumps?

Mark

[sugarwood]

I could not pay $200 to rebuild a part that costs $100 new.
There have to be tens of thousands of Bosch pumps that work fine, and never make it to the forum hype cycle.

It's weird that the SC pump costs more than the 3.2 pump.
SC = 0580254967
3.2 = 94460810204

[tirwin]

There is truth to the old saying "they don't make 'em like they used to." There are many reasons for it.

Replacements built in places with lower costs and lower quality control.

Environmental regulations. Have you ever seen the difference lead makes in paint? There is a reason it was used back in the day. It was fantastic for durability. The effects of lead poisoning -- not so good.

The fact that manufacturers have figured out they can make more money when things are cheap but have higher failure rates.

Our 'disposable' society where it is cheaper to replace things and to repair them.

Lots of people have bought brand new relays that were defective right out of the box.

It's not urban legend.

Here's a list of things that suck off the top of my head.

- URO relays
- Bosch coils made in Brazil
- green oil cooler seals (the ones under pressure)
- generic rear main seals
- oil pressure switch (have to put JB Weld on it to prevent leaks)
- non-Porsche window gaskets

I'm sure there are others.

There almost isn't any part for the 911 that I won't research to see if there are brands that are better than others (or should be avoided). Seemingly brain-dead simple components can have big differences in quality.

One of the worst mistakes I ever made was using a non-Porsche rear window seal.