924Board.org

[RexS]

1980 NA 924.

Sat about 6 years so I expected some fuel system problems. I replaced the external high pressure pump and I can hear it run briefly but the internal one wasn't delivering anything so I decided to replace that one. I ordered one from an on line specialist and it looks right. Even made in Hungary (that is near Germany, right?). I pulled off the fuel lines and drained the fuel tank. Fortunately, it looks pretty clean but the old low pressure pump was in tough shape. The screen had fallen off and the short length of hose between the pump and the tank fitting was toast. I could tear it with my bare hands.

No problem, I have my shiney new low pressure pump that looks exactly like the old one...except it is about 2MM larger in diameter and the pump section does not fit through the big threaded opening!

Has anybody had this problem before? Any great ideas?

I've got the pump in my freezer right now to see if I can buy a millimeter with -40 degree temps. If I manage to get it in, I'll never be able to get it out.
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80 924 n/a
98 Sebring Conv
95 Mustang
97 Honda ST1100

[peterld]

Exact same thing happened to me!

Old pump was exactly as you described...old fuel had consumed the screen and the rubber hose. It all came out easily enough and I left it open while awaiting new pump from the States. Eventually new pump arrived, and just like yours, made in Hungary with correct 928 part number and in Porsche box. Tried to fit it and lo and behold it was 1.0 to 1.5mm thicker than the original. Biggest obstacle was the rivets near the innermost section of the pump......gave them a light file and sand and still didn't fit. Bugger! More sanding...still doesn't fit. Shit!

Thought I'd try the old pump (or what was left of it) and guess what? It won't fit either! It doesn't seem feasible that the opening has shrunk as there is the substantial threaded neck welded into the tank, but something has changed.

Like you I then decided I would try and freeze the new pump and hopefully gain a millimetre or two, but before I do that I now better clean up the markings on the pump body from trying to force it into the tank. I give it a good going over on the wire wheel attached to the bench grinder and it comes up nice and shiny, but is very hot to the touch. Something made me go and try it in the tank again, fortunately with new seal in place, and would you believe it goes in (with a little twisting action).

So now the new pump is in, but probably will never come out again without destoying! Heating expands....yet it fitted???

Haven't tried it yet, but it sure better work.
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80/81 932/8 ROW

[Harm]

wow
Amazing story!

[Joes924Racer]

Yes that was some story. Theres a solutiion here forget the freezer and start grinding and sanding for a bit then when your ready slip it in the hole.
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

[!tom]

I'm guessing neither the pump nor the hole are perfectly round, but close enough that they both look round.
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78 924 NA
5-lug

[RexS]

Thanks, Gentlemen,

I guess I'll start working it over. The threaded boss on the tank seems pretty well machined so I doubt it is out of round.

Any seems wrong that this expensive part has to be modified to fit.

thanks again!
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80 924 n/a
98 Sebring Conv
95 Mustang
97 Honda ST1100

[RexS]

I took a strip of emory cloth that plumbers use for cleaning the surface of copper pipes (it comes in rolls about an 1" wide) and sort of "buffed" the aluminum body of the pump for 20 minutes or so then washed he surface with brake cleaner. It slipped right in the first trial fit!

Note to those who buy a new tank pump: it does not come with the sealing gasket so order a new one at the same time. I did not and thought I'd drop buy the Porsche dealer and buy one....how bad can they be?... Just under $10. At least he had one in stock.
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80 924 n/a
98 Sebring Conv
95 Mustang
97 Honda ST1100