tfarmer96

http://cgi.ebay.com/ebaymotors/5-9-C...00788232QQrdZ1

2500CTD

Just an idea, On our trucks if it gonna be problem, whaat about one of those exhaust cutouts? Just plumb/weld it into the airhorn and throw a switch and it should kill the airflow?

Dieseldude4x4

Some of the old two strokes supposedly would draw the oil vapor out of the crank case and continue to runaway even after you gagged the air to them.. Never saw one do it and don't ever want to.

Lil Dog

Thats basically an PAS, or Positive Air Shutoff. I have one installed on my truck as I am in the Oil and Gas industry. I can't get within 6 meters of a wellsite without one.

Mine is not electronic, just a spring loaded switch to trip the valve closed. My partner has the electronic version that monitors RPM, as soon as it goes 10% over red line it shuts down.

www.rodadeaco.com

roadranger

I witnessed an old Mack Thermodyne run away and blow up with ether.
They were trying to start it on a COLD -20* morning, and just kept spraying ether in the air filter for several minutes while it cranked over. When it finally started, there was so much ether accumulated in the cleaner/intake it roared up WAY past redline and stopped itself by throwing a rod and shattering the crankshaft.

The old GM busses with Detroit Diesels used an ether egg. You put this plastic egg shaped capsule full of ether, slightly smaller than a golf ball, in a container on the blower intake. Slamming the lid down pierced the egg, and a measured amount of ether went into the engine. We were warned NOT to use more than 3 eggs if the diesel didn't start.

I had a runaway with a Caterpillar 3406B when it lunched the turbo bearings.
The crankcase oil pouring out the bearings down the intake caused it to take off like a rocket. I left it in 5th or 6th gear, stood on the brake pedal with both feet, pulled down hard on the trolley, and it took a good 1 1/2 miles to grind down to a stop. When I called it in, the company mechanic told me to 'limp it in'. Told him NO WAY! He was going to be the Hero, and came out in his service truck to drive it back himself. Got the engine fired up in 1st gear, (loaded dump trailer) and smoked the brakes off and still couldn't get it stopped, nor slowed down. It blew itself up when he kicked the clutch in to avoid running right over the top of a car sitting at a stoplight.
He literally loaded up his shorts, too!

Had a similiar incident with a Mack Maxidyne. The mechanic came out and changed the turbo on the side of the road. Unfortunately, he didn't drain the intercooler, so when he fired it up it ran away on all the accumulated oil in the intercooler and blew up. He had the air filter cannister disconnected, and when it took off he tried to stuff a rag down the intake. That rag ended up getting sucked thru the turbo, accomplishing nothing.

By the way, both of those companies had ZERO idling policies, and would not even allow idling for turbo cooldown. What little they saved in fuel, they more than lost in turbos and engines...

Ahhh the good old days of trucking!

Hoss

Wow...here I am driving a diesel powered truck and I've never even HEARD of this before.

So, basically, if some form of fuel gets sucked into the air intake then the engine will begin to burn that fuel and it will do so until either the fuel source is gone or the engine blows up?? Interesting. I suppose just turning the key off wouldn't do anything since the fuel is coming from an outside source??

- NomoreidlingwhileIfillupwithdieselHoss

phox_mulder

You are correct.

If you're idleing at a Diesel only pump, you don't have anything to worry about,
it's the gas pumps next to the Diesel pump that could turn into a problem.


phox

joefarmer

I need one to compete in the DHRA. How much is a mechanically activated one? Who distributes the Roda Deaco line? Where does it mount, right before the intake horn?

Thanks!
brandon.

Smkndzl

LOL remind me of a runaway I had in the shop once with a 6-71 inline detroit. tech just did the overhead on it and I had told him to leave the valve cover off and put a lock pliers on the rack for the first fire, that thing just ran away and there he was grabing for the intake shut off and it kept going and I am watching from the other side of the shop, he jumps on the tire and sat his behind on the air intake to the filter and it kept running away, I finally got there with a hammer and knock the fuel filter off..... whew, there was oil everywhere with the valve cover off , but he forgot the locking pliers. I fire it up again with the rack lock and it was fine after that. LOL next day he came in with the biggest behind hicky I had ever seen

Gear Poet

I had a runaway a few months ago with my engine. Paint fumes.

Calmly but quickly I took off the AFE PG-7 air filter and replaced it with the factory stock air filter that came with the truck. That shut the engine down immediately.







....

2500CTD

Ok now I understand runaways what what about valve float? wouldn't the loss in compression prevent further rpm increases? or?? Its interesting to hear about runaways.

jrs_dodge_diesel

I don't know to much about valve float but its not an issue as far as a runaway is concerned apparently. The lower end (crankshaft, connecting rods) let go before the top end does.

TreeFarm

It doesn't even have to come in the air intake. It just needs to get into the cylinder(s) somehow. Oil getting past the rings caused it on a WWII tanker loaded down with av gas, according to my old high school chemistry teacher. He was in the Merchant Marine at the time, and worked in the tanker's engine room. He said they dumped every CO2 bottle and all the rags they could find into the intake before they got it stopped.

He quit the Merchant Marine the first chance he got.

Lil Dog

Firstly I am surprised you would need one to drag race, but thats the rules I guess.

Mine is a spring loaded butterfly valve and it mounts just before the intake horn. They just cut about 3-4" out of the intercooler pipe and place it in the line. I will shoot some photos today if I can an put them in my gallery.

Depending on your mods, they have different diameter units for all intake systems, so if you have fabbed up an aftermarket intake horn with a larger diameter line, they should be able to have one.

Cost...they aren't peanuts. My electric solenoid actuated one was around $1000 CAD (~$840 US). The cable pull type ones are around $700 CAD(~$585 US).

Distribution... I am not sure as this company is only about 1 hour north of me. I would crack the yellow pages and find a truck outfitter (flat decks, pickers, winches, tow trucks etc.) as they should carry that sort of thing. If not, just call the boys at Roda and they should be able to help you.

PM me if you need more info...

walexa

Several years ago a guy working for the local trucking company......can't think of the name right now.......was working on a big rig and it started running away with him.......quickly he hopped his butt onto the air intake and the suction was so strong that it did severe colon/intestinal damage. It really messed him up. I believe he still works there, but he walks hunched over from whatever damage was done to him. Moral of the story, be careful what you try to do to stop a runaway.

Waylan