worf928

Today I found a cracked and leaking fuel line from the regulator to the fuel cooler on an '89 that's been out of commission for about two years. The motor mounts and oil pan are recent replacements. I know this because a) the motor's high and rocks back and forth, b) the pan isn't leaking, and c) it's not the OEM gasket.

This car's been waiting for me to unbolt and pull the intake for a few days. The rails have been out since Friday so any fuel from the injector/rail pull evaporated. When I went to pop the intake loose I had to tug hard enough that the motor rocked a bit on its fresh mounts. I started smelling gas. WTF?

That rear fuel line flexes a bit every time the motor rocks on good mounts. The line was cracked in the vicinity of the first bend. Every time the motor rocked on the mounts a drop of fuel would drip out of a crack in the line.

So, the moral of the story? If you do the MM/OPG dance with your decade-old (or more) mounts , make absofriggenlutely sure that the rear fuel line is in good condition.

The front fuel line also needs to flex. So check it too.

Note to self: Oh Roger....

the flyin' scotsman

Great advice Dave.............I replaced all fuel lines this year and those 2 at the back of the engine (regulator to cooler; regulator to damper) were in sad shape.

Anyone out there on the fence phone Roger for a great kit price.

blown 87

I could not believe how bad mine looked when I did them.
It is something that i tell every 928 owner that is mandatory and show them a picture of the black one on fire.

worf928

I've replaced a few sets as PM and always check them thoroughly when they are exposed. This is the first one I've found that was actually leaking. Scary $hit. The front hose has the 'oil neck divot' and its right side is turning in the fitting. The U-hose looks fine and the feed line looks fine. But,...

All four lines are going in the round file.

But, the main point of this thread is:

putting in new Motor Mounts could very well cause that rear hose to start leaking. With old dead-flat mounts it's been sitting more-or-less undisturbed for years, not flexing much, and getting nice and plastically comfortable with its shape. But, with new mounts it needs to flex a lot more.

blown 87

Amen Dave.

That rear hose is a almost perfect place to cause a fire.
What you say about it not getting flexed for years and then all of a sudden there is movement is something that I would have never thought about, but sure as hell makes sense.

worf928

I never thought about it either until about 10 seconds after smelling fuel after I pulled the intake. And sure enough once I'd cleared the area I did a little rock-a-bye-fuel-line test and ... drip.

Here's a picture. (Note how the previous 'technician' carefully placed the flywheel speed sensor connector back into its factory retaining bracket. NOT. To date: the only speed sensors I've had to replace have not had their connectors in the bracket. Coincidence? Perhaps.)

blown 87

I replaced mine because I have seen so MANY of them go bad, but they have to go back just like the factory had them on a Porsche or a Volvo or a BMW or a ford or a chevy.

If you spend a bit of time looking at TSB's on different cars you come away with the understanding that even the factory has problems with the way they place wires.
I doubt that if I try to save ten minutes by going around what they have done things are going to work out for long.