There is a lot of discussion about deterioration of the fuel lines and fires in late model 944's. In those cars the fuel lines run from the fuel rail down alongside the exhaust manifold on the passenger side. Due to heat from the manifold, the rubber deteriorates, leaks and fuel on the hot manifold starts a fire. On early cars, 1983-1985 (?), the fuel lines run from the fuel rail over the top of the engine away from the exhaust manifold and down in back of the brake vacuum booster on the driver side. Thus they are not exposed to high temperatures and I would not expect the same level of deterioration. On my 1983, the hoses and connections look like new, and I debating on whether or not to replace them. I know, why not be safe and just do it? Probably what I will do, but still, does anyone knows of a case of fuel line failure/fire in the engine compartment on an early car?
Wayne

 

Its not just late model 944s, its all model 944s because the fuel lines run above the exhaust manifold, and the heat from the exhaust causes the rubber to deteriorate/crack, especially after 3 decades.

Probably a good idea to replace, unless the PO has done this already. A couple hundred dollars is good for peace of mind, imo.

 

Good question. I'll give you some observations-
I have been following the Rennlist 944 forum since 2010. I don't really remember any fuel hose failure threads, much less any for the early cars. But that is my memory, take it with a grain of salt. I'm just saying it's not a routine occurance, on this forum.
I do know that when I got my first 944, around 2010, the common wisdom was as you describe. Fuel hose failures, over the exhaust pipe, causing fires. As you say, on the early cars, the failure, if it occurs, won't be right over the exhuast pipe but I suspect there are no guarantees as to where the spray will go.
I have been following the 928 forum since 2015. I absolutely remember several cases of fuel hose failure that resulted in fires and total loss of the car. Common wisdom is on the 928, replace all the fuel hoses. The 928 hoses are in the valley of the V8 and exposed to normal heat but not exhaust heat. The ones on my 928 were indeed very brittle. I replaced them all.
One standard kit to replace the fuel hoses on an early 944 uses a compression tube fitting at the hard pipe on the firewall. That is probably a weak point but my track car uses that setup. Now sold, but the new owner has not called me to tell me it burned to the ground! To really do the job right, you would pull the hard line and get new hoses professionally crimped onto the hard line by a hydraulics shop.
You didn't ask but fuel pressure regulator failures do seem to be common and new regulators are getting hard to find.

 

My recollection is that the short "jumper" damper line with the bend is of particular concern for cracking.

 

No fuel lines on exhaust side, nor is there the short jumper on my early '85. I agree it is best to replace them, even if I haven't done mine yet. (It's on the list.)

 

Frankly, for the 2 944s and 1 928 that I have gone through, all the rubber hoses in the engine compartment are in general no longer flexible and suspect, in my mind. I had the luxury of replacing most of these hoses with new OEM ones. Not cheap but good for my peace of mind.

 

the hoses are 40 years old. rubber hoses have a useful life of maybe 10 years. they need to be changed otherwise they will just dryrot and leak and still cause a fire.

 

I spent a lot of time keeping tabs on the number of early vs. late car burn down horror stories. It was overwhelmingly biased towards late cars. I still replaced them on my 83, but before and then after removal I couldn't get the hoses to show any signs of cracking no matter how hard I twisted them.
The peace of mind is worth it though.

 

Thanks for the input everyone! I have fuel hose replacement kit ready to install, and it will be done at some point soon. My 83 (purchased by me new) has 80,000 easy miles, always garaged in Southern California and the hoses are still very flexible with no sign of cracking. My thinking is that it is heat from the exhaust on the late cars that causes premature aging of the hoses and subsequent failure. This should be less of a problem on the 83 since the hose does not run near the exhaust manifold. Still, I am about where Ton5 was before changing, and I guess I will too. The hoses on the replacement kit I bought (Rennbay) look a lot cheesier with smaller id than the originals!
Wayne