apparently power steering fluid is flammable....

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Last year we built a 408 stroker for our 1970 Cougar; replaced the entire fuel system and almost everything under the hood. Unfortunately we got excited to drive it and delayed some steering work and a trans build. Fast forward to now: sent the car to a respected transmission shop. My own fault for driving it with 2nd gear slipping - apparently took out the forward drum, some bushings, and the pump.

anyway, after the trans build, the shop owner took the car on a few test runs. after numerous adjustments, he was happy with the results - and was just pulling the car back into the shop when he heard a power steering line blow. then saw flames dancing up from the gap between the hood and the cowl.

That was a very unique phone call that I received:
The transmission is back together; shifting very well; I replaced the shift bushings like you asked and adjusted the exhaust - it was rubbing on the transmission. (I could tell from the tone of his voice that there was some bad news coming....) There was a fire.... lucky I was back at the shop and not driving it or you wouldn't have a car. the car isn't too bad....

anyway, other than extinguisher powder everywhere and PS fluid everywhere - there is no damage to the car. We have all 5 of the old lines out and the bottom of the car cleaned up. just need to get the rest of the powder off the engine and install the new lines.

There are more than a few lessons learned here.

Don't get excited and drive the car before it's completely finished. Carry a fire extinguisher when driving a highly modified car. (actually, I already had one in the car)
 
Oh big time, a lot of car fires are due to the high pressure line blowing and PS fluid hitting the exhaust manifold.
 
I'm really glad to hear kt wasn't any worse! Good on you for having an extinguisher in the car! I have a small Halon fire extinguisher in my 1987 4Runner as well as my 1976 Chevy K10 for just such an incident.
 
Originally Posted By: dishdude
Oh big time, a lot of car fires are due to the high pressure line blowing and PS fluid hitting the exhaust manifold.


My Taurus had a rusty low pressure line and it would get air in it and in parking lots it would pop the cap off and spray PS fluid all over the exhaust manifold. I was expecting it to go up in flames one of these days.
 
I usually have a couple of large cans of beer in the car that could be used as extinguishers at a pinch.

Must get some big red labels for them.
 
I'm all for fire extinguishers. Who wouldn't be?

But I have one question relevant to car fire facts.

After a fire breaks out under the hood how often is it unwise to open the hood?

I know, I know, if it's my car I want the fire out PERIOD. The question is how often do the flames follow right up the hood's inside and burn the person opening it?
 
Originally Posted By: Kira
I'm all for fire extinguishers. Who wouldn't be?

But I have one question relevant to car fire facts.

After a fire breaks out under the hood how often is it unwise to open the hood?

I know, I know, if it's my car I want the fire out PERIOD. The question is how often do the flames follow right up the hood's inside and burn the person opening it?


Hood liners are also usually designed to detach from the hood and smother the flames.
 
And being a 1970 he might have had a genuine asbestos hood liner.
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They say you can spray the extinguisher through the grille, which would work, but you'd want to hose the caustic powder out really really good.
 
Yeah, common misconception. Every fluid in a car is flammable at some point. Ford Escape with the turbo engine did some car-b-cues when the coolant would get onto the turbine housing and catch fire.

Reminds me of a test I was in charge of on the old L31 350s at GM. It was to validate the connecting rod bearings, so there was a full throttle run-up to redline followed by snapping the throttle shut and getting back to idle quickly, repeat. The exhaust manifolds were glowing hot, and the piping was cherry red all the way to the floor. At THAT point, the high pressure side of the power steering line ruptured and sprayed the glowing hot exhaust manifold with nearly all of the fluid in the system. The dyno cell tech and I both hit the big red OH [expletive]! button to shut the dyno off, and then pulled the CO2 fire supression. The flames still got all the way to the top of a 10 foot tall dyno room in the 15 second delay that they system had to let you get out of the cell before the CO2 was dumped. The speed at which the fire got out of control was the most shocking thing. It went from a regular test to an inferno in 10 seconds.

By the way, you could never open the door unless the engine was at idle, for reasons like that.
 
PS fluid is a hydrocarbon so what do you think? If you are going to have fluid spraying on hot parts, you better be using Fyrquel or some other fluid that won't ignite. The vapor/smoke produced by those hydraulic oils will make you sneeze and choke you but they won't ignite.
 
I recall when I was going to school working on the "A" part of my A&P, we watched films on aircraft brake systems. One of the films showed a large aircraft brake assembly being brought up to high speed and then a hard brake application. The brake assembly finally turned white hot and disintegrated with brake fluid spraying everywhere. Lot of smoke but no fire. I believe the brake fluid was Skydrol. For power generation, we used Fyrquel in the hydraulic control units (EHC) for actuating main steam stop valves and turbine inlet steam control valves. I believe Fyrquel and Skydrol are both phosphate ester based fluids which required special o-rings and seals. No matter how precise a planner made the work instructions, we never completely stopped the use of wrong seals. EHC fluid at 3000 PSIG makes a huge mess, including attacking
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almost all painted surfaces. The stuff was an excellent paint remover.
 
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