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2006 3litre Chev motor rotation

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budgie14

Regular Contributor
Hi,since when did these 3litre 140hp Chev motors go to LH rotation?Looking at one in a 2007 Raeline for sale,but its no good to me if its LHR as my Alpha one sterndrive upthrusts the diveshaft into the tapered roller brg[mines about 1986 alpha].any advice appreciated
 
LHR is looking at the motor from the belt side. Looking at the motor from the flywheel side it is rhr.
The motors are clockwise looking from the flywheel side that has not changed. Counterclockwise looking at the motor from the belt side.
Your actual problem is the year of the motor. you need one 87' back. Give this a read ....
3.0 years that can swap
 
Master mechanic said:
LHR is looking at the motor from the belt side. Looking at the motor from the flywheel side it is rhr.
The motors are clockwise looking from the flywheel side that has not changed. Counterclockwise looking at the motor from the belt side.
Your actual problem is the year of the motor. you need one 87' back. Give this a read ....
3.0 years that can swap
Click to expand...

Ayuh,... You've got that exactly Backwards....

The 3.0l is, 'n has always been a left-handed motor, as viewed from the workin' end...
It is, 'n has always been a Standard rotation motor....

The crankshaft bolt pattern changed around '90, or '91...
But, there are adapters available to swap in a newer motor...
 
Ditto Bill.
Industry Standard dictates that all engines are viewed from the flywheel end when determining rotation.
Whether I/O, I/B in either conventional transmission or V-drive, this has been the standard, and will likely always be for auto and marine.

Standard LH rotation is CCW when viewed from the flywheel end..... same as Car/Truck engine.

faq-ro5.jpg


Reverse RH rotation would be just opposite of this (above), and will be CW when viewed from the flywheel end..... typically a Starboard application.

(there are some exceptions, such as the goofy early Chris Craft installations that deveate from industry standard)





.
 
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Chris, you would have to throw that into the mix! :mad:......... :)

That, and the Goofy Chris Craft orientation (driving from the front of the crankshaft :mad:) could be confusing to some.

Bottom line..... view from the flywheel end, and you will not make a mistake..... whether Goofy CC orientation, Port side being RH, or ____ ___ !

.
 
Thank you for the elucidation.So its the same as a normal engine,just viewed from a differrent end.Just to say that ever since Ive been in the Automotive industry ,since 1967,we have always viewed motors from the front,as thats the end we work on mostly,so saying right hand rotation was normal,as thats the way we hand wound the motor when checking cambelt marks ,doing tappets,points gap,etc etcAll the w/shop manuals stated right hand rotation.It was ground into us as the norm.saved a lot of confusion.Thats why this boat motor had me puzzeled when it said LHR.I now know about the flywheels being different.
 
budgie14 said:
1... So its the same as a normal engine, just viewed from a differrent end.

2... Just to say that ever since Ive been in the Automotive industry ,since 1967,we have always viewed motors from the front, as thats the end we work on mostly, so saying right hand rotation was normal, as thats the way we hand wound the motor when checking cambelt marks , doing tappets,points gap, etc etc All the w/shop manuals stated right hand rotation. It was ground into us as the norm. saved a lot of confusion. Thats why this boat motor had me puzzeled when it said LHR. I now know about the flywheels being different.
Click to expand...
1... I too came from the Automotive world originally.
As per Industry Standard in both Auto and Marine (as far as I know) these are always viewed from the flywheel end.
I guess we could look at it this way:
The left side of a vehicle is only the LEFT side when sitting in the driver's seat looking forward.
If we're looking at the front of the engine, the LEFT side now becomes the passenger side.

Driver's side = Left.... passenger's side = Right.... flywheel rotates CCW or LH Std Rotation.
IOW, always view things as though looking at the working end of the flywheel.

2.... I'd suggest that somewhere in the mix, the engineers and/or the Tech Writers became confused.:confused:


Master mechanic said:
Exactly opposite of what i posted when i rolled out of bed.
Click to expand...
Did you roll out of bed RH or LH rotation.... and where was your flywheel during this? :D
 
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Reading it this morning i could not believe it was me posting that. You are a true gentleman. Allowing me to remove my foot from my mouth so easily.
57 years and counting guess getting the thoughts to the fingers to type it gets reversed.
Won't happen again.
 
Don't get this confused with the correct way of looking at engine rotation.

Interesting post a couple of weeks ago I was in a conversation with a Mercruiser certified mechanic with over 20 yrs experience about a 5.7l sea water pump #807151a9 if you view the impeller housing from the flywheel end it has an arrow going ccw with R/H rotation stamped on it I asked him to explain this one to me after about 10 minutes we both were confused went and talked to about 3 other mechanics everyone was confused. The service manager finally called a mercruiser engineer they said it has always been stamped that way to show which way the impeller rotated even though it was stated wrong it meant ccw looking at the flywheel backside but r/h looking from the front of engine when rotating the pulley. How to confuse everybody and not fix it is mercruisers answer I guess.
 
Again, some of this is apparently lost in the translation when reduced to text by the so called "Technical Writers".
You can bet that the engineers got it right.... but those who wrote the text made a mistake.... or just simply weren't complete with the info.

Merc has had many more year and mid-yeat model changes, and/or part changes, over the years than most Marine companies.
Look at Merc's parts lists compared to Volvo Penta.
Perhaps this explains a portion of the in house confusion. :D
 
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