Mike Frye

I did my fuel lines this weekend. I had been waiting, thinking it would be so involved that it should wait until my top-end refresh, but after seeing what was required with Adam G.s car, I decided there was no reason to wait.

The whole thing took only a few hours and didn't even require me to pull the intake side boxes. Here is the minimum amount of work that is required in order to do this job (I think):

1. Order kit from Roger
2. Run car and pull FP fuse (# 42) or relay so it runs out of gas and depressurizes the fuel system
3. Disconnect battery (no smoking during this job either!)
4. Remove air tubes, airbox and MAF (You can already see all of the lines that need to be replaced. Mine has 5) I also pulled the crossmember, but I don't think even that is required.
5. Bleed the front of the passenger (US) fuel rail by removing the nut and ball bearing. If you have a FP gauge there, remove that instead. Catch a little bit of fuel.
6. Begin removing the fuel lines:
There are two combination lines on mine: They are the first and last in the fuel flow. The first is the one coming from the fuel tank, it's got a rubber section where it makes the bend at the front of the passenger side cam cover, then it changes to a hard line to cross to the DS fuel rail. This one that crosses the front has got a clamp or strap holding it to the bracket that holds the idle adjuster test port. We had to unbolt this bracket and remove it to get the line to feed out and back. We also discovered that if you use a counter-clockwise twisting motion it's easy to unsnake this line through all the plug wires and clockwise gets it right back where it belongs over the cam cover and through all the wires.
The second combination line is the fuel cooler return line. It's got a hard line bend and a rubber section.

In addition there are two lines that need to be completely replaced with new hoses (one has just clamps on both ends, the other has swage fittings, you need to keep the ends from this one, but cut the fittings off and replace them with the new clamps. These are also in the back, the U-shaped one is the one with the fittings, the longer one is just a section of hose with clamps.

The remaining hose is supplied with Roger's kit, it is the replacement hose section already equipped with the fittings and it connects the front of the fuel rails at the front of the engine.
NOTE: Adam G. found a 17mm flat wrench at a bike shop to counter hold the passenger fuel rail because a standard wrench won't fit. It worked perfectly for this job.



Once you replace all of these, double check that all the clamps are tight, replace the fuse or relay, plug in the battery, standby with fire extinguisher and crank it up!

What we did was replace the MAF, but we didn't put the airbox or tubes back in so we could see all of the fuel lines when we cranked it up. After we could tell there were no leaks, we put the rest in and started it again.

Thanks Roger, I'm good for another 20 years. And thanks for helping me out Adam.

I'm still planning the intake refurb, but I don't tense up quite so much when I crank it over each time, knowing that at least the fuel lines are brand new.

I know there are other write-ups on this, but I know I felt like it was a much more involved job, especially for the lines at the back of the engine, but they're all easily accessible by just pulling the airbox and MAF. I just wanted to let everyone know that it doesn't require a lot of tear-down and rebuilding. It can easily be done on a weekend before lunch from start to finish.

As a side note, now that I think about it, before I replaced my motor mounts my engine was sitting more than an inch below the crossmember, this probably caused some serious stress on these old fuel lines (the feed line on the PS and the return line at the firewall). Just another reason to replace them!

Sorry for the long post and thanks for reading!

ROG100

Mike,
Thanks for taking the time to write this and I am sure many are going to benefit from it.
Roger

Jim bailey - 928 International

We do see a lot of fire cars and it is NOT PRETTY .

Jim R.

I would bet that after taking a set for 15-20 years these old lines will not take well to being moved or stressed. Mine are replaced (thanks Roger!), and anyone doing a pan gasket and/or motor mounts should really take the extra couple of hours to replace these lines. Crispy Sharks suck!

Jim

marton

Does this fuel line replacement go all the way back to the fuel tank or just around the motor?

Marton

AO

I'm sure this kit only addresses the "soft" lines, but not sure if it also addresses the lines back at the pump/filter. The hard lines shouldn't need replacement.

marton

Andrew posted
"The hard lines shouldn't need replacement."

I am sure I heard of people who had rust problems with the pipes at the rear; for example the nice GTS that Jeremy Clarkson drove that burnt out after a petrol (gas for you guys) leak under the rear wheel arch.
I checked mine out last weekend & from what I could see the pipes look like new; I did not take any covers off.

Marton

Mike Frye

Marton,

Andrew is correct.

The kit only includes the rubber portions of hose inside the engine compartment. The hard lines would be a different project entirely.

One of Adam's cars has some corrosion issues toward the rear end. He contacted someone and they said they can lay out replacements than wrap them around a 5 gallon bucket to coil them up and ship them out. He said as long as the radius is that large or larger, they can be shipped and unbent without any weakening. I'm a little skeptical, but he said they do it all the time.

marton

Thanks Mike

Marton
also sceptical about shipping coiled up pipe
I know people in England who used small bore copper central heating pipe but you always have a potential problem when you connect two dissimilar metals together.

Sailmed

I'm in the stbd aft wheel well right now. The $300 '78 Euro car starts, but won't run - (posting different thread) - fuel pours out from behind the cover. The same problem occured with the $1000 car. The steel lines are rusted and the rubber is all dried out and rotten too. Seems that WYAI you might consider that all the rubber needs replacing from age. Realizing things are a bit hotter in the engine compartment - but a little trapped H2O in the wheel well = rust, and rubber still rots with age.
I'd take the little extra time and refresh them ALL - Just my 2c worth.

Dwayne

Very nice, Mike! THANKS for the writeup - I need to plan to do this on the 88 since the lines there are 20 years old. Now I know it can be done without too much complication or time. THANKS!

Hilton

There's a few soft lines at the rear that age badly too.. whilst none of these are high-pressure lines, they can all still result in fuel or vapour leaks, which is a problem if you're being measured by an advanced emissions testing center. I failed on Hydrocarbons in two successive tests in the chamber. Fixing my very broken Y-connector and replacing the lines around the tank cured the leak.

Granted that the pressurised ones up front are more of a fire risk, its still good to make sure your fuel and vapour are properly contained

• The tank to external pump line - $15 and may reduce the chances of pump death (a few reports of bits of lining from this hose getting into pumps).
• A return line that attaches to the top of the tank on the level sender - a short section of 3/8 hose will replace it - the original is crimped onto a hard line, but that can be dremelled off and replaced with a clamp. My old one was very crusty - it crackled when squeezed.
• There are also two ventilation hoses (they attach to either end of a T just behind the fuel filler neck). These don't carry fuel directly, but I had a significant vapour leak from one of them that caused my Hydrocarbon levels to fail me in an emissions test. One hose loops from the tank body back to the neck, and the other goes from the tank to the expansion tank under the rear-right fender. One of these was leaking for me.
• There's also 2 soft lines off the front side of the expansion tank. One from the tank to a check valve, and another from the check valve to a hard line. I left these alone for my emissions test, but will get to them when I'm doing my intake job in the next couple of weeks.

Adam Geist

The fuel lines (hard lines) that Mike mentioned previously I had purchased from a well-known Porsche dismantler. Since the fuel lines were 8'+ long, they bent the fuel line around a 5 gallon pail at the midpoint to shorten the shipping length to 4'.

The 5 gallon pail provides a gentle bend (without kinking) that straighens out very well. A major supplier of remanufactured fuel/brake lines for muscle cars does the same thing for easy of shipping.

Adam

Mike Frye

Thanks for the additional comments Mike, Dwayne and Hilton (Thanks for more things for my list ).

Adam, I misunderstood, I thought he was coiling up those hard lines. Instead they just bend them in the middle so they don't have to send the full length. Thanks for the clarification.

Bill Ball

WYAIT, don't overlook the fuel accumulator. I've seen them leak.