3.2 Carrera Main Fuel Line Replacement

[RKC]

Just wanted to say thanks to Pelican for this thread and one other I can't seem to find right now:

Notorious Carrera 3.2L rear fuel line leak revisited (long)

I replaced my nasty, expensive pressurized fuel lines this weekend, and couldn't have done it without this site, 101 Projects and Bentley.

One thing to add though. I couldn't get the main line out until I realized that if I took the right/passenger side intake manifold off, I could just slide it out to the right and install the new one in reverse. That made it much easier to maneuver and reminded me to tighten the intake manifold bolts (18ft lb) as long as I was in there (they're always coming loose on 3.2's and leading to idle problems/misses).

Thanks again to the posters for their info - and Wayne for his parts!

[RKC]

Here's the other post from Pelican - posted from someone who found it on another site. As I said, I DID need to remove the right intake manifold, but was careful to cover it from any dropped loose bolts.....


Here's the other post:

Below is a post to Rennlist by Wayne Michelsen which he wrote shortly after doing this repair without removing the intake or engine. I used it as a guide when I did the same and I remember it being pretty accurate. Again, I'm not saying this is the best way, especially if you are experienced at engine removal. If I were to do it again, I might remove the engine but would not consider removing the intake.

Original Post Wayne Michelsen wrote: ---------------------------------------
I recently reported a near disasterous failure of my pressurized fuel line in
the engine compartment. What follows is a little background, and my best
post-mor tem recollection of the repair.

This document is written with the following perspective:
Front - refers to the firewall/cabin/cylinder-3,6 end of the engine
Back - refers to the bumper/tail/cylinder-1,4 end of the engine
Left - refers to the driver/cylinder-1,2,3 side of the engine
Right - refers to the passenger/cylinder-4,5,6 side of the engine

Background:
The pressurized fuel line assembly of the '84-'89 Carerras is a manufactured
assembly of brass/alloy tubing and flexible rubber/compound hose. The assembly
extends from the fuel filter (mounted on the drivers side of the engine
compartment across to the middle front of the engine, then turns 90 degrees
toward the back (bumper) end of the engine where it branches in a 'T' to
connect to the back end of the fuel rails.

There is a second pressurized 'bypass' fuel line that goes across the front
end of the fuel rails from the fuel pressure regulator on the left to the
fuel press ure damper on the right. This is also a rubber/compound hose with\
end fittings. This fuel line is Porsche Part #:

It appears that the heat of the engine dries and degrades the rubber hosing.
The problem is (arguably) accelerated by the new oxygenated fuel. Eventually,
the rubber hose begins to crack, leak, and in my case, spray fuel. Needless
to say, this is VERY bad!

I have written this with the assumption that you are replacing both fuel lines,
the main fuel line assembly, and the 'bypass' fuel line. The main fuel line
assembly is $478.35 (now), and the 'bypass' fuel line is $30.00. Also, the
'bypass' line is a trivial added effort. So, Alayit. ["As long as your in
there" do it.]

1. Remove the heater blower and ducting.
- First, remove the black heated air elbow duct. (8mm socket where it
connects to the blower, and flat screwdriver for the ring clamp where it
connects to the heat exchangers)
- Move the distributor cap out of the way. Don't disconnect the plug wires,
just loosen it so you can get at the mounting screws for the main heater air
intake. (screwdriver) 10mm socket and wrench on the air duct bolts.
- Remove the big black heater air intake duct that goes from the engine block
cover to the squirrel cage fan. There's one bolt at the bottom behind the
distributor, one bolt on the side of the fan shroud, and two bolts on the
backside of the duct. (10mm socket and open end wrench for the screws, and
a flat screwdriver for the ring clamp)
- Remove the heater blower fan/motor. (10mm socket for the three lock nuts)

2. Unbolt the sensor plug holder mounted on the side of the left intake
manifold. You don't have to remove nor disconnect the three sensor plugs, just
unbold
the holder from the intake manifold. It makes life easier, later on, if this
can be moved around. (10mm socket for the two mounting screws)

3. Remove the air filter and air filter box.
- Unclip the four latches at each corner of the air filter cover and remove.
- Unbolt the air filter box from the air flow meter and remove. (10mm socket
for the four mounting screws inside the box and the lock nuts inside bottom and
on the side of the box. Philips screwdriver for the two screws holding the oil
breather lines mount/support to the side of the air filter box)

** Now life gets harder **
4. Unbolt the fuel line end mounting tongue. It is on the left side, back at
the far end of the left fuel rail. It's held in place by a 10mm screw and is
a b*tch to get at. (10mm short open/closed end wrench and small hands)

5. Unscrew the fuel line middle mounting bracket. It is located at the far
side (front) of the engine behind, and slightly left, of the throttle housing.
It holds the brass fuel line, near the elbow where it turns to head up toward
the alternator. It also holds the bypass fuel line, and part of the wiring
harness. The mounting bracket is held to the support by a long (3") screw with
a 4mm allen head. Warning: This is a total PITA to get at, and harder to put
back. (4mm allen wrench and long contortionist arms with small hands)

6. Remove the middle mounting bracket's support. In step 5, you removed the
bracket, now remove the support to which it was attached. This is done by
removing the 10mm nut holding it onto the engine case. (10mm socket and
extension.... don't drop it)

7. Unbolt the fuel line center mounting tongue. It is located just above and
behind the alternator where the fuel line brass tubing branches to the two
sides. (10mm socket)

** At this point, the fuel line assembly should be moveable. It's still
connected to the fuel rails and fuel filter by rubber hoses, but the brass
tubing section should be free now.

8. Disconnect the fuel return line and bypass fuel line from the fuel pressure
regulator. The fuel pressure regulator is located at the far end of the left
fuel rail. The fuel return line goes from the left side of the fuel pressure
regulator to the firewall under the engine lid hinge. The bypass fuel line
goes from the right side of the fuel pressure regulator to the fuel pressure
damper at the far end of the right fuel rail. (15mm and 17mm open end wrenches)

9. Remove the fuel pressure regulator. In step 8, you removed both fuel lines.
Now, pull off the vacuum line from the top. The whole assembly is mounted to
left side of the intake manifold. Remove the mounting bracket screws from the
left side of the assembly. (10mm socket for the two mounting screws)

** Note: removing the assembly (bracket and regulator) is easier than removing
each individually.

10. Disconnect the bypass fuel line from the fuel pressure damper and remove it.
(far end of right fuel rail). (15mm or 17mm open end wrenchs, and a pair of
snips to cut the plastic cable ties)

11. Disconnect the main fuel line assembly from the fuel filter (top), and from
the near ends of the left and right fuel rails. (17mm open end wrenches)

** At this point, the entire fuel line assembly should be free. It's still
trapped under the intake manifold, but it should be free to move around.

12. Optional: Remove the lower throttle mechanism spring. This is the one
located under the intake manifold. I removed it to give me just that little
bit of extra room.

13: Optional: Disconnect the TDC sensor plug and move aside. This is the
sensor plug connector located right in front of you as you look at the engine
above the alternator. I removed it to give me just that little bit of extra
freedom.

14. Remove the fuel line assembly. Take your time and try to navigate it
through the the maze and out the far side (front/passenger/firewall end) of
the engine. I don't know what else to suggest. It just takes perseverence
and determination. All I can tell you is not to worry. For me, the new one
went in much easier than the old one came out (YMMV).

** Everything goes back together in reverse order of the way it came apart.
No tricks, not magic. Just perseverence and determination.

Good Luck.

[rusnak]

Did you replace with ss braided lines, or go with the oem one? If you went the ss route, how did you find a source, or where did you have the new rig fabbed up? Thanks, thinking about doing this myself soon.

[RKC]

Actually used the OEM ones - there was a price drop from $500+ to $300+ last year and I jumped on them. Was avoiding the job all winter.

There was just a thread on a place to get them made up in the past few days. I'll try to find it.

[RKC]

Here's the link to the braided ones.
Carerra Fuel Line