Fire..

[ian]

Yesterday evening after 2 or 3 months standing I decided it would be a good idea to start up the car. After turning over several times I got it going but noticed it was running very rough, as if the choke was out, which it wasn't. I reved it several times to try to clear it and there was a bang, smoke came from under the bonnet and there was burning petrol on the floor and in the engine bay!! Luckily I had a hosepipe to hand and managed to put out the fire within a couple of minutes, apart from a couple of scorched cables I can't see and major damage. What could have caused it? Thanks in advance

 

[ian]

Any thoughts anyone?

 

[mojobaby]

Hi Ian, when you say "the floor", do you mean the inside of the car? I don't have any idea how that could happen. All apertures from the engine bay for steering column, handbrake, gear lever, pedals, cables etc should be sealed.

Is it possible that you have neighbours with a grudge?

As for the engine bay, trace the fuel line from the petrol pump, through the carb to see if any fuel lines are pierced or loose. Also check that the carb is firmly bolted down and all your manifold bolts are tight.

Is your fuse box inside or in the engine compartment?

Hope you discover the reason so that others may be warned and take precautions

 

[chudson]

The floater in the carb could stuck after not having fuel for two months causing flooding but this would probably do more harm than dammaged fuel line or fuel pump membrane.

 

[ian]

Hi Ian, when you say "the floor", do you mean the inside of the car? I don't have any idea how that could happen. All apertures from the engine bay for steering column, handbrake, gear lever, pedals, cables etc should be sealed.

Is it possible that you have neighbours with a grudge?

As for the engine bay, trace the fuel line from the petrol pump, through the carb to see if any fuel lines are pierced or loose. Also check that the carb is firmly bolted down and all your manifold bolts are tight.

Is your fuse box inside or in the engine compartment?

Hope you discover the reason so that others may be warned and take precautions

Hi. The burning petrol was outside, on the floor under the car, it had spilled down from around the carb I think, the fusebox is inside the car

 

[ian]

The floater in the carb could stuck after not having fuel for two months causing flooding but this would probably do more harm than dammaged fuel line or fuel pump membrane.

I think that was probably it, doe you think it will have damaged the carb? if the floater was stuck would this cause a lot of flooding and with me reving the engine cause the explosion of petrol and subsequent fire?

 

[Piet]

This was the bane of old rear engine renaults using the ventoux engine. The carb is directly above the starter, as in the R4. A fuel leak in the line to the carb causes fuel to pour over the starter, or a stuck float or needle valve does the same. Then, when car won't start, or stalls, hapless owner tries again. Sparks from starter cause it to catch fire. I had this in a 4CV and a friend lost her beautiful Floride from this. In your case I'm a little surprised because it appears there was no ignition source unless possibly petrol was getting everywhere (blown around by the fan?) and set off by a sparky dynamo or alternator?

It is less likely to happen in later 4s because the starter and its cables are more encapsulated

 

[reidalpine]

could it be Ethanol-mixed fuel has eaten away at your rubber-hoses? Yes I know-I'm at That again! -R.

 

[ian]

This was the bane of old rear engine renaults using the ventoux engine. The carb is directly above the starter, as in the R4. A fuel leak in the line to the carb causes fuel to pour over the starter, or a stuck float or needle valve does the same. Then, when car won't start, or stalls, hapless owner tries again. Sparks from starter cause it to catch fire. I had this in a 4CV and a friend lost her beautiful Floride from this. In your case I'm a little surprised because it appears there was no ignition source unless possibly petrol was getting everywhere (blown around by the fan?) and set off by a sparky dynamo or alternator?

It is less likely to happen in later 4s because the starter and its cables are more encapsulated

Mine is a 1985 model with the engine in the front, petrol must have poured out from somewhere for there to be burning petrol on the concrete floor below.

 

[ian]

could it be Ethanol-mixed fuel has eaten away at your rubber-hoses? Yes I know-I'm at That again! -R.

It runs on normal unleaded petrol, I'm begining to think it was a stuck float in the carb, thats why maybe the engine felt like the choke was choke was pulled out