Pete

Hi Y'all,
I've been a rennlist member for 15 or so years since I purchased my first Carrera which, alas, caused me to neglect my beloved '86 944. After sitting in my shed for 5 or 10 years and my driveway for 5 before that, I now want to bring her back to life. Last winter I went into the shed and noticed a puddle under the rear of the car. Yes, it was gas and the leakage turned out to be a couple of gallons before the tank was empty or at least until it stopped leaking. I know replacing the tank is a fairly major effort (including dropping or removing the trans-axle to remove the old tank) and what I'm wondering is if any of you that are more experienced than I am with 944s might be able to relate your experiences with fuel leakage. I know the tank is plastic and I wondered if there were any fittings low on the tank that may be common sources of leaks and that might be repaired without replacing the tank? I haven't been under her yet for a real inspection but just preparing myself for a possible fix.

Thanks and I'm sure I'll be back!
Pete

Gage

Most likely the cause is the supply hose from tank to the pump has failed. Plan to replace that hose, the strainer in the tank and gasket (read about how to not strip the insert for the strainer), the pump, the filter and the high pressure hoses either side of the filter. The tank is likely to need cleaning also.
Important to replace all the hoses on the engine side as well. Fuel injectors will likely be stuck too.

Pete

Hey thanks for the quick reply, Gage. I figured the injectors would probably need attention. Can all the hose replacements you mentioned be done with the tank in the car?
Thanks again,
Pete

Gage

Yes, tank stays in. Once the tank end components are complete and with fresh gas in the tank you can bypass the DME relay to run the fuel pump and circulate fuel through the system. This is a chance to check for leaks prior to introducing spark and will sometimes clear injectors too.

ElRicardo

Gage is right about reading about how not top strip the strainer. I think, but I am not sure, that he may actually be referring to the threaded insert that the strainer screws into. This threaded insert was molded into the tank when it was roto-molded many years ago, and can be literally rotated out if you over muscle the strainer. And that, my friend, is where the real trouble starts. You can read many posts on how to epoxy it back it (with gory little details like "tempering the plastic", "roughing it", etc) but just like the dreaded hatch re-seal, there really is no permanent fix, only replacement with a good tank. So be very cautious about how much force you use. And if I sound parochial, ask me how I learned this...

But fortunately, the leak is most likely the short U-hose that connects the tank strainer to the pump. All 3 cars I have resurrected have had this tube completely rotten! Of course,.that many years of bad gas - ooof. Plan on pulling injectors and having those cleaned and flow balanced,. New pump, probably. Certainly aforementioned strainer and fuel filter. Also the fuel level sender may be "frozen" in the bottom (empty) position and this may need to be cleaned and put back into commission. After all those and you will have a functional fuel system! Then you can start on everything else!

Pete

Hey thanks Ricardo. Yes, Gage clued me in on the strainer thank God and described how the sleeve was installed just like you did. His approach is to drill out the old one. I may do that but more than likely I'll just leave it alone as I know it isn't plugged because I leaked out a few gallons of fuel! I'm getting her back on the road to sell it to a long-time buddy who has bugged me for years to buy it. If he decides to replace the strainer I'll pass along your and Gage's advice.

Gage hit the nail right on the head with the tank to pump hose being the culprit, The outer rubber portion was melted to where it looked like a heat gun had been used on it, melted down to the braided inner part.

We're almost neighbors, I live in Urbana, IL. Haven't heard much if anything about Iowa re COVID-19. You must have a more reasonable governor than we do.

Pete

ElRicardo

yes We are practically neighbors. “Reasonable” is just a point of view. Envious of the Carrera, but I have my 944 to keep me warm (and my driveway spotty!)

Pete

Good-looking pair!