Engine compartment fire

[Zef]

We rarely see the cars on the highway with a burning engine. It's seem more frequent for Porsche cars..at least on the board...I wonder what can cause this high frequency...apart the age of the cars...My 911 is 25 years old now and I don't want this to happen...so what to check and improve beside the fuel lines...Thanks...Syl

[72 four door]

Look for frayed wires, but fuel lines are the main culprit make sure your spark plug boots are not cracked

[eR1c]

I had a car catch fire on me (about 16 years ago). It was a early model 1974 Ford/Mecury Capri that my father and I put a mustang 5.0 V8 into. The culprit was the edelbrock air filter/housing. The carburetor backfired and lit the foam element air filter on fire. That was a sweet car, -anyway, I always carry a fire extinguisher in all cars I own.

the air filter:
http://www.rjays.com/Engine%20Parts/air_cleaners_imgs/ede1002-lg.jpg

not the one that caught fire, but similar model:
http://www.capriclub.com/grm/gr9.jpg

[Superman]

Isn't there a fuel line or fuel rail that sometimes fails on the Carrera models? A part that's spendy and hard to get to, but a good idea to replace?

[Bobboloo]

The culprit is the drying out and cracking of the rubber in the fuel lines. Rubber is usually past it's healthy life in 10 years.

Most 25 year old cars have already gone to the crusher but our 911s are usually the exception to that rule. If there were more 25 year old cars out on the road you'd see them burning as well.

The insulation of the wires in the engine compartment also get brittle and crack from age and the heat of the engine. Combine the two and voila.

[RWebb]

Agreed - it is mainly age.

BUT, notice how the idiot designers ran the electrical wires and panel right next to the fuel lines -- what genius thought of that?

They should have put put them on opposite sides of the engine compartment.

[the]

What Bobby said.

Also, your carrera does have a somewhat complex "rear fuel line," which is a one-piece combination hard line/soft lines. It has at least 6 separate crimped on points, so there are a lot of points on it where it can leak. Plus it is almost completely hidden between the engine and the firewall, so it isn't easy to inspect. And it costs $350-$500 or so for the factory part (although others have successfully had hydraulic hose shops rebuild theirs).

Add all of it up, and it is not a part that is routinely replaced. In other words, it goes until it fails. If the failure is a slow leak, it is usually discovered and replaced, but if it is more of a catastrophic failure, the result can be catastrophic.

[Porsche-O-Phile]

I bought this:

http://www.*****************.com/product_p/essfire-5.0-liter-kit.htm

As well as a battery master switch cut-off in the cockpit. No B.S. I learned the hard way with my 951. Trust me. Get it. Now if there's a fire I flip one switch and pull one T-handle. 99% problem solved and car saved.

Don't f*ck around with fire protection. Trust me on this.

[KTL]

Zef,

Do a search and look for what "the" and Superman make mention of. The original Carrera 3.2 fuel supply line which goes from the fuel filter to the fuel rails on the intak manifold is prone to leaking.

I've seen a number of these leak at the crimp joints and also at the original swivel fittings. The replacement Porsche OEM line is a double crimp with non-swivel fittings. By the looks of the new line, the old line was definitely a challenged design.

There are also MANY people on this board who have rebuilt their old fuel lines in many ways. Some rebuild the old line by cutting off the crimp collars and replacing them with crimp clamps and new hose. Others bring their fuel line to a specialty hydraulic hose shop to have it duplicated with new fittings and braided stainless shielded hose.

You'll also want to replace the hose the is at the back of the engine near the wall of the cockpit. There's a short hose there which connects the fuel pressure regulator and the fuel system damper. This hose is also of the same original design. And there's one last hose that many people overlook. It's a tiny hose that connects the bottom of the fuel pressure regulator to the fuel tank return line.

The suspect hoses are #'s 9, 11 and 19 in the following parts diagram

http://www.pelicanparts.com/PartsLookup/HTML/911_USA_84_86_KATALOG/107-05-Frame3.htm

[dad911]

I had a braided line split this summer. Lucky no fire, but the engine was doused with fuel.

I happened to see 3 car fires this summer, along the Jersey highways. No Porsches. It wouldn't surprise me if the new fuel formulas/additives are deteriorating the lines.

[patkeefe]

At the risk of sounding like a moron. I have set my SC on fire four times this year. Three while welding on it (last night was the latest event), and once from puking out oil which dripped onto the heat exchangers. The Porsche undercoating material will burn pretty easily, I can tell you that. You don't even have to burn through the metal, just get it hot enough, and the undercoat on the other side of the weld will combust.

Needless to say, I have a fire extinguisher on the roll bar, and at least five other FE's in the garage. I can usually just pat the fire out with my gloves (except for when I welded the bracket into the smugglers box for the battery relocate, and the flames were lapping at the fuel tank...got the FE out on that one).

I think the combo of very warm engine compartment, electric wires and fuel lines mixed together, etc, makes the 911 a fire trap. And, the nylon fuel lines are a nice touch.

[imcarthur]

Original 1987 fuel line:



Ian

[DRACO A5OG]

+1 on Age, I am very cautious when working in the engine as not to break or cause the rubber/plactic to fall apart.

I recently checked my plugs and #6 plug cover is torn, Thank GOd I have new wires on it's way.

I can always remember that 911/930 maybe on fire off of Sunset on the grass near UCLA.

It was not only on fire but shooting blue flames out it. The devistated owner was bout 30 yards dumb founded. Only if he had a fire extinguisher. He could only watch, how sad.

That will never happen to me, if I can't help it.

I just purchased a Max Out (ABC rated) for about $50. Lays right behind the Passenger Side Seat, velcroed down. I'm also taking her to the track for the first time in December. Besides the Helmet, I thought that was the next important thing.

[jonbot]

This has been something that's been on my mind since I picked up my 28 year old car a couple of weeks ago. Inspecting these hoses is one of my next high-priority projects. What about the hoses that go from the fuel distributor to the injectors, what are they made out of, and are they something to be concerned about as well?

[sjf911]

Originally Posted by RWebb

Agreed - it is mainly age.

BUT, notice how the idiot designers ran the electrical wires and panel right next to the fuel lines -- what genius thought of that?

They should have put put them on opposite sides of the engine compartment.

How about placing them right above the exhaust manifold when your autoignition temp is 500F.

[Bobboloo]

Originally Posted by RWebb

Agreed - it is mainly age.

BUT, notice how the idiot designers ran the electrical wires and panel right next to the fuel lines -- what genius thought of that?

They should have put put them on opposite sides of the engine compartment.

Ain't that the truth.

I smelled raw gas once driving my old 72' MFI Coupe up on Mullholland so I pulled over. A fuel line had ruptured and was spraying my CDI. Boy that was a close call.

I cut the end of the line off and reattached it to get me home. The next day I replaced all the lines.

[rusnak]

omg I'm going to check my fuel lines.

I noticed a few weeks ago that 911SCs use about 80psi, while the 3.2 uses about 40psi of fuel pressure. That's still high.

My 914-6 once had a fuel line blow apart at the crimped brass fitting that fitted onto the rubber fuel line between the carb throats. The fuel pooled between the left and right side carburetors, and then gushed all over the hot engine. Lots and lots of boiling gas! It was scary but lucky for me, no fire.

What kind of fire extinguisher would be good to carry, just in case?

[euro911sc]

Originally Posted by DRACO A5OG

I just purchased a Max Out (ABC rated) for about $50. Lays right behind the Passenger Side Seat, velcroed down. I'm also taking her to the track for the first time in December. Besides the Helmet, I thought that was the next important thing.

Velcro is not good for heavy objects that are prone to fly around under heavy braking. Bolt it to the car somewhere Or, I guess, you could wear your helmet around town

Can we modify the fuel lines to use some other fitting/hose combo that is used today? doesn't every fuel line end at a threaded body? What's the thread size?

Best regards,

Michael

[RWebb]

I like the Halon extinguishers - they don't destroy the motor.

[DRACO A5OG]

Originally Posted by rusnak

What kind of fire extinguisher would be good to carry, just in case?

From my brief research, you want a minimum of electrical and fuel fires (B and C respectively) A is other combustable fires

I chose the smaller MAX Out because it will not spray the white stuff all over the place and create a more of a mess. If you are on a Budget the white stuff will do, at least the fire would be out. Also, It fits better under the passenger side seat in the rear.

Originally Posted by euro911sc

Velcro is not good for heavy objects that are prone to fly around under heavy braking. Bolt it to the car somewhere Or, I guess, you could wear your helmet around town

Actually, the tank fits snug on it's own the VELCRO is for extra measure so it won't slip out when I accelerate or slide side to side. When I brake the seat itself keeps the heavy tank in place. The quick release is facing up towards the rear seats. I tested and it was within immediate reach. I put it there because I did not want to put holes in the frame to mount it and it's also hidden away so IDIOTS won't try to steal it on the street. I live downtown and there are some reall DEE DEE DEE's who like steal the most retarded things out of people's car. I don't need to advertise