471 Detroit Diesel

[Tenwheeler]

Make sure you have 3 ways to shut that engine down in case of a runaway.

Three ways? 1: Intake plate or flap. 2: Vise grips in rack. 3: Cut fuel line?

 

[Vetech63]

Three ways? 1: Intake plate or flap. 2: Vise grips in rack. 3: Cut fuel line?

YES! …..except I will just clamp off the fuel line and starve it.

 

[DMiller]

Unless is pulling engine oil!!! AIN'T Nothing to stop it then!

 

[Vetech63]

Unless is pulling engine oil!!! AIN'T Nothing to stop it then!

an explosion......LOL

 

[kshansen]

an explosion......LOL

If that appears to be going to happen run on a line parallel to the crank shaft not at a 90º to the crankshaft. And don't come back just because it gets quite as it may take a few seconds for whatever went up to return to ground and you don't want to be there to catch them parts!

 

[Tenwheeler]

Unless is pulling engine oil!!! AIN'T Nothing to stop it then!

How about dumping the fire extinguisher into the air filter intake?

 

[RZucker]

How about dumping the fire extinguisher into the air filter intake?

That might slow it down for a millisecond. Detroits move a lot of air normally. If it's running away on oil... All bets are off. A fire hose might stop it. Saw a 3-71 that went down bubbling in a lake, bent 2 rods and was running again the next day.

 

[kshansen]

How about dumping the fire extinguisher into the air filter intake?

Might be tempted to do that with a CO2 extinguisher but not sure I would want to dump a dry chem one down the intake. If you did I would think a major tear down would be the next step.

 

[Vetech63]

Might be tempted to do that with a CO2 extinguisher but not sure I would want to dump a dry chem one down the intake. If you did I would think a major tear down would be the next step.

Isn't that what pressure washers are for!? LOL

 

[kshansen]

Isn't that what pressure washers are for!? LOL

Yes, after engine is completely disassembled down to bare block!

I would not suggest using the pressure washer to clean the inside of the intake while engine is running. See above post by RZucker!

 

[DMiller]

Even the CO2 leave a residue, Been there DONE that, ain't fun!!

As to the pressure washer, hydrostatic lock is NOT pretty!!! especially at HIGH speed RPM!

 

[Tenwheeler]

Might be tempted to do that with a CO2 extinguisher but not sure I would want to dump a dry chem one down the intake. If you did I would think a major tear down would be the next step.

I just meant into a paper type air filter. Heard of it but never done it. Just asking.

 

[DMiller]

Is really ugly when performed. Took a week of cleaning to get what the CO2 either had In it or displaced by using it out of a 6v53, just NASTY! It did have a oil bath AC on it though. Could see it effectively snuffing the DD runaway, but also collapsing the instantly frozen paper filter into the intake.

 

[kshansen]

I would guess that anything you may resort to in an attempt to stop a run-away situation can have results that may not be totally perfect. Then again compared to picking shrapnel pieces like connecting rods or sections of flywheel out of your face they may look good in the end.

Wondering if the CO2 froze the oil in air filter and the restriction caused gunk in filter base to get sucked up and into engine.

I know first hand how getting a bit too much water in the oil of a running engine can whip up some nasty stuff that is like filling crankcase with grease.

That was either a 3 or 4 -53 running a water pump. Seal on the water pump the engine powered had failed and was spraying right at the rear seal of the engine. I seem to recall the low oil pressure safety switch shut it down before any major damage.

 

[DMiller]

My suspicion was it displaced a considerable amount of that oil and grime locked with the mesh element, was pretty much still full(minor loss) on clean up of the mess. There was a whiteish material strewn throughout that little DD when I did tear it open, air boxes, liner ports, crusted cooked to the heads, intake piping, did not think they had powder in them but this was like EVERYWHERE.

 

[old-iron-habit]

If a Detroit runs wild from sucking engine oil why would shutting the air off via a board, estop, or other means not stop it. I understand that shutting the fuel off would have no effect. It can't possibly get enough air from the pan with the oil to keep running wild could it?

 

[RZucker]

If a Detroit runs wild from sucking engine oil why would shutting the air off via a board, estop, or other means not stop it. I understand that shutting the fuel off would have no effect. It can't possibly get enough air from the pan with the oil to keep running wild could it?

It will, if the E-stop is working or you have the blower bonnet off to use the board. A lot of the later engines had spring loaded rack levers and no E-stop flaps. Mostly the 92 series engines, but I have seen 71's with that setup too.
Had a 6V-92 in the shop once that had those wonderful check valves on the airbox drains that left a steady pair of oil streaks on the floor when I backed it out. The oil rings were shot and it would push oil out the liner ports and build up til the airbox pressure open the check valves. Pulled it right back in and gutted the check valves so it could blow clean. Just an old farm truck.

 

[DMiller]

If a Detroit runs wild from sucking engine oil why would shutting the air off via a board, estop, or other means not stop it. I understand that shutting the fuel off would have no effect. It can't possibly get enough air from the pan with the oil to keep running wild could it?

Oh yes it can and they would, suck the seals on the blower shafts, and any point they could to push enough air into the cylinders to light them up. Saw a few old engines with tired seals guy go to shut them down and do that just chugged on until ate enough oil to dry the block out and seize or just get cold enough to die.

 

[kshansen]

I think the key here is that with failed seals it would be possible to get enough air to keep the engine running but not enough to get a true run away going up to wild RPMs and literally exploding.

I would have to think that in the vast majority of cases the E-stop will do it's job and kill engine before major damage.

I would hope no one would remove the "blower Bonnet" and depend on using a board to kill the engine! I know I would not want my hands getting that close to those spinning rotors in a blower. To lazy to check the spec's but believe the blower(s) are running at a 2:1 overdrive compared to engine speed. So at the rate the engine might take off in an runaway situation you would be looking at those rotors spinning at 5,000 rpm or more. Not sure how much of your arm they would eat before killing the engine!

 

[DMiller]

Seen one 8V71 eat a shop service manual and NOT flinch!! That engine was fresh overhauled and the guy ran the rack wrong, ended up could NOT shut the fuel off so threw his 71 series shop manual in the blower, was gone in a blink!! Another guy covered it with a section of plywood and killed it as the tech cleared the shop door running out. Engine was re-rebuilt but had to have the blower replaced and a lot of the sub structure gone thru that had not been(me working it), ate a LOTS of Stuff including having to get a reground crank and two rods(spun two). Previous mechanic did not stay to finish the job, loaded tools and left.

ALWAYS keep the Emergency head on the blower on a restrart after working the engines. The 53 I had run away the E'flap was eroded in the pin retainer holes YEARS earlier and been INCONVENIENTLY discarded(AHEM, by me).