KATOOM

I do realize what you guys are talking about but I have to say I dont really see why or how this product would ever be needed. I mean thinking about the fact that there is no venturi butterfly in the intake that stops air from coming in. So the theory is that any fumes from other fuels like gas could enter the air intake and cause the engine to over speed. Factoring that there is NO restriction means that the engine is operating at max CFM all the time. Diesels running on a totally different A/F ratio than gas. This would mean that a lot of alternate fuel would have to enter in the system to permit a correct air to fuel ratio for anything to happen. What is the chances of this happening anywhere you could take a breath of air, let alone at a public gas station. Has anyone ever actually seen this happen? I've never even heard of this before but I've heard of diesels that ran for miles on gas before popping. I think it is a one of those things thought up by someone paid to think up think up stuff that has no knowledge of whats being regulated. You know what I mean.

AlpineRAM

I saw and witnessed 2 destroyed VW diesels due to engine oil overfill- the oil foamed and was thrown out of the crankcase vent into the intake. Engines overreved and threw rods. (Even though inj. pump was shut off).
I also saw a Steyr truck (local brand over here) run away with the guy frenetically trying to stop it from the pump due to spillage of fuel from a barrel onto the air filter inlet. Truck engine was wrecked, driver had sheer luck that none of hte parts hit him (trying to use the manual stop on the inj. pump).
I can't imagine that a combustible mixture existing on a fueling station and nobody noticing it, but I can imagine spillage of fluids or high pressure LNG causing a runaway on a site.

Jst my 2c

AlpineRAM

Helicopter Dan

Enterprise Engine is using one in their truck you could try calling then Like DarrellB said onthe hp Twin pullers some rules require them. Doug @ EEP 740-246-6329

Lil Dog

[quote author=KATOOM link=board=4;threadid=5565;start=15#msg216750 date=1070339118]
...So the theory is that any fumes from other fuels like gas could enter the air intake and cause the engine to over speed. ...... This would mean that a lot of alternate fuel would have to enter in the system to permit a correct air to fuel ratio for anything to happen. What is the chances of this happening anywhere you could take a breath of air, let alone at a public gas station. Has anyone ever actually seen this happen? ......[/quote]


In the industry we use it for you are around "gas" all the time. Not gasoline but natural gas and a whole bunch of other ugly chemical compounds that a diesel would love to run on. This is not ment for gas-oline stations rather having your truck on site with tools, and a pipeline is flared or gas is vented and the truck runs away on the gas. I have heard of it happening and there is just cause to have these units installed. These are not for the average vehicle.

J-eh

KATOOM

I guess I could see that happening around a natural gas line or propane. How much does one cost and why wouldnt it work in decelerating like and exhaust brake (but not with such force)? Or maybe working in conjuction with a exhaust brake?

Lil Dog

The fully electronic RodaDeaco system runs about $1200 CAD installed. My buddy has one on his Dmax... You can get a manual version for about $800.

The problem with the valve as a brake is that it is not a butterfly system. Its a spring or solenoid actuated slide valve that is open or shut, no in between. The electronic versions have a solenoid that is activated at 105% of redline and then holds shut till 0 Rpm is reached.

scuzman00

Another interesting tidbit about the need for the shut-off is that they are not there just to protect the engine...they are there to protect the plant in which the engine decides to scatter. When engine goes boom.... the surrounding plant makes BIGGER BOOM,which, exponentially expands at the rate of how many other fuel sources are readily available to keep the BOOM cycle recurring.

It has happened down here many times in the petrochemical industry over the years....Hard lessons learned the hard way.

P Kennedy

Cummins Alberta has them and installs regularly on gensets and truck engines for oilfield application. For the uneducated an excess of airborn fuel can be released from several sources including un-purged fuel/crude oil tankers, pipelines and any remote metering or compression station. There are products transported in trucks, railcars or pipelines more volatile than gas or diesel such as condensate or bitumen solvent. Under the right circumstances an engine runaway could happen in less than 15 seconds as the people at Trimac Calgary witnessed one night in the shop when a un-purged and steamed tanker was placed in a warm shop. The truck sat inside for 20-30 minutes releasing residue vapors, the ceiling fans pushed the vapors down onto a truck that had been inframed and at the same time was in start up mode. The mechanics turned over the 8V92 attempting to prime/bleed air from the fuel system, the gaseous air was drawn into the intake with the diesel compressing it and igniting. The flywheel blew up at 4200 RPM blowing the cab from the frame and imbedding the 3-4 flywheel fragments in several items including the roof. The positive air shutdown if installed could have been tripped and all inflowing air/fuel movement effectively stopped. The potential of a secondary explosion of the fuel tanker and residual fumes in the shop could have been deadly as the flying pieces were striking other metal and concrete objects causing sparks. Just one example of why they are a required piece of equipment in fuel rich oilfield environments. Just think about this next time "Johnny in a Hurry" fuels his running truck on warmer days when fuel vapors come from fuel tanks being filled with liquid expelling combustable vapors which travel at air intake levels. PK