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One last diesel noob question- the running backwards thing can only happen with a two stroke, I'm ASS-uming?
I've seen it happen on 3 different 4 strokes as well. A Mitsubishi Bulldozer, an NHC-250, and a LDT-465 (deuce engine). The dozer was a pain in the ass. We couldn't stall it and turning the key off didnt kill it. Ended up having to yank the fuel line. All 3 also shit exhaust out of the intake and ruined the air filters.
 

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When a 2 stroke diesel runs backwards,the intake and exhaust still function normally. The direction that the crank turns makes no difference.



The only issue I'm aware of is the oil pump may be direction sensitive.


Wouldn't the blower(s) turn backwards?
 

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I've seen it happen on 3 different 4 strokes as well. A Mitsubishi Bulldozer, an NHC-250, and a LDT-465 (deuce engine). The dozer was a pain in the ass. We couldn't stall it and turning the key off didnt kill it. Ended up having to yank the fuel line. All 3 also shit exhaust out of the intake and ruined the air filters.
Wouldn't the fueling event be out of time? (now you got me thinking,lol)

Also, oil flow through stuff like main bearings might be a problem since some are designed directionally. (not directed at you specifically, just the backwards running engine discussion in general) :D
 

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I had a Cummins run away
Nut came off the turbo got sucked in, shredded the turbo so all the oil going to the turbo was getting sucked into the engine

Floor mat over intake didn't do anything

Split two Pistons broke the crank


Sent from my iPhone using Tapatalk
 

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6v71 has exhaust valves in the heads just like a regular motor. The slots in the sleave is the intake ports. The 6v71 has 4 exhaust valves per cylinder. The engines will not run without the supercharger. If you get into the engine for any reason leave all the carbon build up. If you start scraping it and dont get it all out its a bad day.
Exhaust valves in head. Intake thru ports in cyl sleeve
Whoops, made sense in my head at that moment. I'm too young to have seen much more than 60 series come through on the regular.

Either way, principle is the same. I don't know of any 4 stroke that can go backwards unless it was intended to.
 

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Wouldn't the fueling event be out of time? (now you got me thinking,lol)

Also, oil flow through stuff like main bearings might be a problem since some are designed directionally. (not directed at you specifically, just the backwards running engine discussion in general) :D
Nope.

The fuel still goes in at the same time.

And youll start burning your oil as fuel..

As for the previous blower question statement. Yes the blower will spin backs and just like you think its product will come out the intake. They will run without the blowers, just not make any power.

Ive slammed the mouse trap (the block off plate on the blower) shut and it kept running.

Interesting engines.
 

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I've had a cat 3306 in an old 980b loader run backwards. Was lifting the bucket and stalled it right as I kicked the lever off the detent. Took a second to figure out why the intake was blowing dust out and it was reversing all the sudden.

Edit we had an old ford water truck that was a Detroit and a Warner Swasey excavator as well. As everyone has mentioned they leaked like crazy (rust prevention feature) and are loud as hell. Not particularly good on fuel. But stout and great for new drivers as they are much harder to over rev.
 

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:laughing::laughing::laughing:

I've seen them run backwards and run away backwards. I don't remember what the common issue was that caused it, but 90% of the time it's someone inexperienced.
Same here. I'm not sure what caused mine to, but hearing that thing wind out with exhaust coming out of the air cleaner will wake you the fawk up! lol
 

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In order to properly drive a 2 stroke Detroit, first, get into a huge fight with your wife, then slam your thumb in the door, then spill your coffee on something important. You drive that engine like you hate it, and you're trying to rip it out of the truck.

Whilst I've never actually seen it happen, they can start and run backwards.
Gets real interesting when it happens. I've been present for two instances. Was driving during the one. First time driving I made the mistake of lugging the engine going up a hill in West Virginia. It backfired, rolled backwardsand all of a sudden we were accelerating down the hill. I got it stopped and finally was able to stall the damn thing out. Took me about 20 minutes to pry the seat cushion out of my ass so I could check the truck over. Old timer stopped to check on us and gave me the golden advice to run it like you want it to blow up. That old dump truck is still running up and down the mountains on the Ohio/West Virginia line.
 

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Had a buddies ktm 495 ex dirtbike hiccup, stall and start back up and off he went doing a burnout in reverse. / hijack off.

Oh, and did anyone tell you to buy moar oil yet, you should.
 

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Also as has been previously stated if it ain't leaking run because it's getting ready to explode. I've never seen a Detroit that doesn't leak oil. My pastor's big offshore boat has a pair of 6-71 TIBs in it. It has two huge tubs under each engine and replaceable diapers mounted to the bottom of each engine. When he first got it he used to go easy on the engines. He became a convert after we used less fuel coming back from a fishing trip by flogging it then when we went out just cruising.
 

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One last diesel noob question- the running backwards thing can only happen with a two stroke, I'm ASS-uming?
Nope, any mechanical diesel can. I had a hand cranked 2 cylinder diesel running an air compressor bump off TDC when it was being cranked to start, started backwards, pumping exhaust out the air filter, suckling air through the muffler. Scariest part was the 18" crank handle that cams out when the engine fires, if it fires backwards though it won't come loose, and starts flailing at camshaft speed...
 

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Wouldn't the blower(s) turn backwards?
To set them up for reverse rotation you swap parts in the cam geartrain, the top end of the engine still runs the conventional direction. Some later cranks are rotation dependant for oiling though, and can't be reversed.
 

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When a 2 stroke diesel runs backwards,the intake and exhaust still function normally. The direction that the crank turns makes no difference.

The only issue I'm aware of is the oil pump may be direction sensitive.
Ok,:D. I guess all that dust coming out of the air filter on the fender was just an anomaly. I remember it well because we were pouring a foundation and that chute nearly cleaned all of us off the wall.
 
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