I've searched but still need help fuel leak

[Rodek]

All,

My '78 SC is springing fuel leaks under the front stone guard. Most recently (after the car has sat non-running for two weeks and today outside temperatures are cooler than they were two weeks ago) a steady drip from the front passenger side of the car while the engine was running today. I had it at the dealership recently to determine the fuel leak to no avail. It simply wouldn't leak there.....even before my very eyes.... Today though, I caught it on video. At this point I believe all of the fuel lines (front/rear) are original and also believe that it's time to replace them all before my car ends up being unintentionally crispy.

I'd like to ask all of you to help me compile an inventory list of the fuel lines, fittings and whatever else you think I should replace (front/rear of car). If anyone finds the time to help me, I'd really appreciate it.

[Rodek]

I attached a photo of the leak.

[Tremelune]

Looks like the fuel pump. I believe that stone guard comes off with a few bolts. Have a look.

[steely]

+1 I have to agree, but I have to add that I don't have a 78. Certainly the FP and connections from it to the tunnel (feed and return lines) and the fuel tank are right there. There is even a "T" up there in some models.

Is it possible you are seeing slosh running over the stone guard?
(It may have blown off in the drive to the dealer)
Just wondering of the dealer removed the guard when they looked.

There's tons of SC owners, you should be able to get help from them and/or the PET catalog or even Pelican for your list of clamps, the correct diameter fuel rated line and the FP itself.
You're probably doing this, but keep her outside in the meantime, and good luck. You've got this.

[DRACO A5OG]

+2, fuel pump, most like the rubber hose to the right in the pic:

[Rodek]

Thanks for the replies folks. The dealer did have the guard off and we didn't find any leaks during two separate trips there. The temperature outside was much warmer than it is now though. If my senses are pointing toward the same direction yours are, it could be a pinhole leak in that line next to the pump (cold temps making the line shrink) or like you said, the pump itself. I'm starting a note for myself to keep tabs of the parts needed to fix this little gremlin.

Thank you again for your replies, advice and photos. They are of great help to me.

[dap930]

If those are the original fuel lines, they are long overdue for replacement. They are not compatible with ethanol in the fuel today. I would contact Len Cummings, "BoxsterGT" on the forum for replacements lines front to rear. He only answers email: len@autosportengineering.com. The new rubber hoses he makes are compatible with ethanol. Do a search for posts by "BoxsterGT" and you will find several posts with the products he offers.

[Mark Salvetti]

I've talked to Len about the fuel hoses in my 79, which should be identical to yours. The rubber hose on the right side of the fuel pump in the photo is the fuel pump suction line, so no pressure on it. If it is leaking, then that's an easy fix since it is only held on with hose clamps. You'll have to drain the fuel tank, though.

The fuel pump hose connection on the left is the high pressure feed to the engine. The other hose connected to the fuel tank at far left is the fuel return line from the engine. Both of these hoses connect to the fuel lines in the tunnel. The problem is that the connection to the tunnel lines is a crimp that can't be separated. If you have to replace these lines you'll have to cut them off, and then replace them with a set from Len that would be held on with hose clamps. Porsche doesn't make replacements.

If you don't like the idea of hose clamps and barb fittings on the pressure side, then you'll have to also buy new central tunnel lines from Len that have fittings to connect to fuel pump lines that Len also makes with fittings. That's probably the best way to go, but definitely the most work.

You can get new tunnel lines from Pelican, but not the front fuel pump lines. I also don't think Porsche makes all the engine compartment fuel lines between the tunnel, the fuel filter, and the engine. There again, Len is the source.

Mark

[Rodek]

Thank you dap930. I will e-mail BoxsterGT as well as try to contact him on the forum. I also noticed you mentioned ethanol. Yeah, the car was ran with ethanol fuel for a while until I found a reliable place that carries non-ethanol fuel. Unfortunately I won't have that luxury if I travel away from my area.

BTW, are the tunnel lines rubber as well?

[Rodek]

Mark,

Thanks for breaking down the lines, connections and describing the lines in the picture. This is the exact kind of information I'm looking for. Did you end up replacing everything on your '79 and if so, how big of a job is this? I'm not the most mechanically inclined when it comes to my car yet. Its been reliable up until this point. I can change oil, due some electrical and clean the heck out of it though.

[Dodge Man]

IMHO Age dictates replacing the fuel lines. I lost the tank outlet line on my 911 and I was fortunate that I had my water heater & gas dryer 24 inches off the floor(to CODE). A CAR-B-QUE is not what you want to happen. Get OEM replacements or make up new hoses with FI hose & salvaged old fittings. Dremel cut off the sleeves(carefully) and have a local hose shop crimp new hydraulic sleeves over your new FI hose. A lot of farm equipment is now metric so most hose shops will be able to get the sleeves. Best of luck.

[Rodek]

Dodge Man,

You offer great words of wisdom. Thank you for sharing! I'm planning on replacing the lines front and rear and just for good measure, the fuel pump as well. I'd hate to have a situation like you described. Thankfully my car resides in a stand alone garage far away from the house.

[Mark Salvetti]

Originally Posted by Rodek

Mark,

Thanks for breaking down the lines, connections and describing the lines in the picture. This is the exact kind of information I'm looking for. Did you end up replacing everything on your '79 and if so, how big of a job is this? I'm not the most mechanically inclined when it comes to my car yet. Its been reliable up until this point. I can change oil, due some electrical and clean the heck out of it though.

The fuel lines in the tunnel are plastic, know as polyamid. Same as the lines to your fuel injectors. They supposedly rarely go bad. The problem is where those tunnel lines transition to the rubber lines at the fuel pump.

I haven't gotten around to ordering a set of lines from Len. I just have too much going on right now to work on the car. My engine and fuel tank are out, and replacing the tunnel lines should be pretty easy. Much harder with the engine installed. Someone that's actually done it will probably chime in as to how feasible this is for you to tackle yourself.

Check out these threads: Okay- so I am going to replace my main tunnel fuel lines tomorrow. Any suggestions?

How hard is it to change the fuel lines?

You'll find a lot of relevant threads if you enter "polyamid" in the search field for this forum.

Mark

[Rodek]

Thank you again Mark. I was curious about those tunnel lines. Also, thank you for the links. I'll read them.

[Rodek]

Ok. Here's an update. I'm going to a local air cooled specialist to see about getting new fuel lines installed on the car along with a few other minor things.

[Rodek]

Update again. The car is scheduled for a an evaluation of the leak and remaining fuel system components next week. Hope to report back with some good news.