Engine turns backward???

GB SISSON said:
I had an old 6 cyl landcruiser and I was dribbling atf down the throat of the carb trying to decarbonize it from what could be an old wives tale, but this isn't... After a couple minutes and some hiccups and near stalls, it hiccupped and started running backwards. It started racing up really fast so I went into the cab and switched off the ignition. No change, just mad acceleration. I can only think it was running as a diesel, fueling itself off hot atf sucked in from the oily wet exhaust and probably a pool in the muffler. There was a geyser of black crud exhausting out of the carb and the tailpipe was now the intake. Should have stuck a potato in the exhaust to kill it, but was just too freaked out watching this happen. Before this I had no Idea a normal 4 cycle gas engine can run so well in reverse. I would have thought the cam would have needed to be ground differently like a twin engine boat. But they can run backwards. No I didn't get a video.
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John Deere two cylinder diesels would do this if stopped at top dead center. Made a mess when the exhaust would blow the oil from the air cleaner all over the place.
 
I agree Mart. As soon as the rain stops and the ground dries I'm going to do just what you suggested.
A couple of clarifications:
-the engine was turning but did not run on its own when the rotation changed while rolling in gear.
-the starter turned the engine in a clockwise rotation each time we tried to start the engine using the starter.

No wacky weed was in use at the time either...although a few beers were tempting afterward!
 
welcome to the 'Barn...sounds like you're having fun....kinda....good luck with your dilemma....got pics of your car....we love pics....Mike
 
Try jacking up the rear wheels hit the starter and selecting gears forward and then reverse and see what happens!!
Fordestes
 
The kiwis built a 3 wheel off road buggy called the Gnat back in the early 70s, I think NASA even ordered one. They had 3 forward and 3 reverse gears. To select reverse you turn the thing off and turn the key the other way and the motor ran backwards. Not sure on the details though. Nope they never really caught on.
 
my4dv8 said:
The kiwis built a 3 wheel off road buggy called the Gnat back in the early 70s, I think NASA even ordered one. They had 3 forward and 3 reverse gears. To select reverse you turn the thing off and turn the key the other way and the motor ran backwards. Not sure on the details though. Nope they never really caught on.
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I spent three years in Germany in the air force `56-'59. I recall there was some German civilians dragging out logs from behind the main hangar. They were using a huge rubber tired tractor. We marveled as they would restart the engine to back up and restart it again to go forward. We assumed (I know) they were reversing the rotation of the engine. It could have been a diesel, I don't remember..
 
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Reversing a Caterpillar engine will blow the oil out of the oil bath air cleaner. You do not want to do that.
Bruce
 
Just a comment, some marine diesel engines were set up as reversing engines. To make them work, you shut the engine down, shifted the cam and restarted the engine , direct connected to the prop and in reverse you went.
 
My 2 stroke snowmobile has electronic engine reversing which is activated by pressing the starter button a second time after the engine is running. The computer induces an engine stumble followed by changing the ignition timing. In other words, you don't even have to restart the engine--- it automatically stumbles and bounces the pistons into reverse rotation. Works flawlessly.

As noted above, you can't reverse a 4 stroke unless you reverse the intake and exhaust routes by changing the camshaft.
 
Sounds like this thread has become a dead issue as no news since the the 9th.(poster has been online since them) Not much of a surprise there.

R
 
Ronnie said:
Sounds like this thread has become a dead issue as no news since the the 9th.(poster has been online since them) Not much of a surprise there.

R
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That doesn't mean we aren't all still having fun telling our 'backwards stories'.....
 
I think a few auto school kids playing with the ford barn.
Flat head other then boats don't run backward, and when you make car you don't want 50/50 chances with assemble so the rear-end can not be put up side down.
Piece work made so you don't think. And I like the switch to make it run backward kids. Have fun boys.
 
George/Maine said:
I think a few auto school kids playing with the ford barn.
Flat head other then boats don't run backward, and when you make car you don't want 50/50 chances with assemble so the rear-end can not be put up side down.
Piece work made so you don't think. And I like the switch to make it run backward kids. Have fun boys.
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George, what part of a pre-'49 rear axle is offset? To my knowledge, the pinion gear is centered in the center section, the housing bells are each machined the same, and the axle shafts are the same length. When assembling, the ring/spider/axle/carrier unit is installed from the left or driver's side, right? What prevents someone from mistakenly installing the unit from the passenger side?
But I do agree, this engine suddenly reversing rotation story seems to be a hoax!
 
My six cyl wasn't a flathead, but it ran backwards with no doubt whatsoever. What really made me mad was that the old rusty muffler and exhaust system was feeding the cylinders the filthiest, grittiest mixture ever for combustion and the newly rebuilt carb was acting as the muffler for all this abrasive, oily mess. Took 3 evenings to clean the engine compartment. And what's an 'auto school'?
 
The way the gears are made they only go one way. And the center section is made NOT to go up side down. The bolt pattern made to be a no brainer.
Most all starters turn engine clockwise. Boats with twin screw one may go other way.
If you were out front pulling a car would you look at dist.
Now if you were puling it backwards in 2nd it would go backwards.
End this thread.
 
Yup kill this turd of a thread 4 cycle engines don't run backwards. Some have snorted farted and burped but that is not running. I'm with George kill this issue. :)

R
 
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