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JanetGroene · 17-02-2011, 10:27

The story started, “It wasn’t funny at the time but....” Happened to a friend of a friend. Hoping to save money on a starter for his marinized Chevy engine, this bloke bought an automotive starter but without attention to rotation. You guessed it. It started fine but sucked half the bay into his engine.

S/V_Surya · 17-02-2011, 11:13

I did not think that was possible. I thought engines will only run in one direction. I have never heard of this and I am older than dirt.

ViribusUnitis · 17-02-2011, 11:15

Detroit diesel engines will run backward.

Chevy gas engines won't.

blgklr · 17-02-2011, 11:52

If a gas engine didn't start but was tried in wrong rotation might it not become hydrolocked? A diesel if does not start right away can become hydrolocked. Thats why if having problems starting shut off water inlet.

**boatman61** · 17-02-2011, 11:57

LOL.... reminds me of when I was servicing a 2x Jawa 350cc bike... got distracted by a pretty girl while I was replacing the timing gear...
Man... did I get a shock when I shot backwards in 1st gear....

They were 'Very Nice Legs' though...

Jesse · 17-02-2011, 12:47

A number of years ago my friend who rode a "Cotton " motorcycle discovered it ran backwards quite well after releasing the decompression lever while pushing it backwards, he would then put the gearbox in neutral and offer it to anyone wanting a ride. Riding "Bobs Cotton" was considered a "Rite Of Passage" and you were rated on time ,distance, and speed. It had a Cornucopia type exhaust system so we couldn't hear the screaming and profanity.

**Jim Cate** · 17-02-2011, 13:20

G'Day Janet,

Well, I think that this is another silly urban legend. As others have already said, four stroke engines, whether gas or diesel, will not run backwards, no matter which direction one cranks them. Don't know what happened to the "friend of a friend", but the story has been embellished beyond belief... like so many others!

Two strokers are a different matter!

Cheers,

Jim

S/V_Surya · 17-02-2011, 13:39

Here is a mythbusters link on this question.

Can an Engine Run Backwards - Topic Powered by Social Strata

courageous cat · 17-02-2011, 13:57

MythBusters this one is busted. You have to get up pretty early to put one over on yuo guys

delmarrey · 17-02-2011, 14:27

I lost a cam shaft in an old LH 409 Crusader. Ended up having to buy twin 427's (left and right hand) just because of a cam shaft.

But i couldn't believe what it dii to the boat. Have you ever seen a 13 ton semi-dispalcement hull up on a plane at 26 kt.

ShaunJ · 17-02-2011, 14:39

I was recently on "John Arthur" an old tug boat with an atlas Imperial Engine. This is a 1942 70' tug, to put it in reverse you would have to stop the engine and start it backwards. this takes about 8 seconds....

ShaunJ

avb3 · 17-02-2011, 15:36

A friend of mine owned a used car lot and got a 911 Porsche in on trade.

As usual, the first thing he did was check the oil; it showed low.

So, he added oil, like we all would, right?

WRONG!

When he started the engine, he promptly blew it as the oil was overfull. WTF? How did THAT happen.

$6,000 later (this was back in the early '80's), he found out you had to check the oil in a 911 with the engine RUNNING, same as when your checking most automatic transmissions.

We all teased him about if for years.

**nigel1** · 17-02-2011, 16:52

Quote:

Originally Posted by ShaunJ

I was recently on "John Arthur" an old tug boat with an atlas Imperial Engine. This is a 1942 70' tug, to put it in reverse you would have to stop the engine and start it backwards. this takes about 8 seconds....

ShaunJ

Quite common on the older diesel engined cargo ships and tugs before CPP became the norm.
Basically the cam shaft is moved to change how the inlet and exhaust valves open/close. The engine is then re-started on air.
Too many starts would use more air than the start air compressor could keep up with, always amusing when the chief calls up to the bridge to let them know they have enough air for one more start.

**James S** · 18-02-2011, 03:06

Quote:

Originally Posted by nigel1

Quite common on the older diesel engined cargo ships and tugs before CPP became the norm.
Basically the cam shaft is moved to change how the inlet and exhaust valves open/close. The engine is then re-started on air.
Too many starts would use more air than the start air compressor could keep up with, always amusing when the chief calls up to the bridge to let them know they have enough air for one more start.

Cool.