Which side for CR outboard on twin install?

[wingtime]

No I'm not installing twins, but I'm buying a Merc outboard that is from a twin engine install and I want to make sure I get the right one since there are no props to look at.  I believe the starboard engine is typically the standard RH and the port is the LH or CCW rotating engine.    Since Mercs serial numbers don't tell you squat is there any way to tell by looking at the lower unit to be sure I'm getting a RH motor?

[GoneFission]

Look at the prop.  The normal rotation outboard motor prop turns clockwise, and is usually the right-hand engine.  The counter-rotation engine's prop turns counter-clockwise and is usually on the left.  

 

Note this is reversed for most inboards.  

Hope this helps - good luck!

[fitz73222]

Usually there is some sort of counterrotating icon on the cowling or mid section that will tell you it is left hand rotation. If in doubt, take off the cowling, shift the engine into forward gear and slightly rotate the flywheel clockwise by hand and see if the propeller shaft rotates clockwise to identify the starboard engine that you want.

[John Jones]

I want to make sure I get the right one since there are no props to look at.

Can you not turn the motors over and watch the rotation of the prop shaft?

If there are no props and you can't even spin the motors with the starter I would be leery of buying a motor I could not run to test it...  $0.02

[seabob4]

Wing,
If the motors still have the model # plates on them, there should be a "C" in the counter-rotator motor model #.  Also look at the very end of the propshaft for a "C" and "R" stamped in it.  You can also shift into forward by sliding the shift slide into fwd (use your current binnacle and see if fwd is push or pull so you know which way to move the shift slide), and rotate the propshaft.  If it turns CW with the motor in fwd gear, that's your engine...

[wingtime]

Well my binnacle was set up for my Force so I don't know if the shift cable pushes or pulls for forward gear on the Merc.  I saw the engine run and did a compression test(good even compression in all cylinders).  Sounds great.  Wicked sounding in fact.  LOL  Since I did not know which way to push the shifter I very well could have shifted the LH motor in reverse and mistakenly thought it was a RH motor or vise verse.  They have the serial numbers on them but no model info.  Seems that all the early to mid 90's Mercs or Mariners I looked at are the same way.  The motor I was looking at was indeed the starboard motor, and another buyer bought the port motor and picked it up before I went to go pick up mine and it was indeed marked counter rotating.  So I think I'm good to go.  Can't wait to get it mounted and rigged to see how much more power I'm gonna have!  

[seabob4]

You're gonna have some fun, that's for certain!

[GoneFission]

If you know the model number, you can see which is counter-rotating.  Here is Mercury's nomenclature:
MODEL TYPE CHART:  
M - ROPE START  
PT - POWER TRIM  
L - LONG SHAFT (20")
XL - EXTRA LONG SHAFT (25")  
EXL - EXTRA EXTRA LONG SHAFT (30")  
E - ELECTRIC START  
C - COUNTER ROTATION  
H - TILLER HANDLE STEERING  
O - OIL INJECTION  
OS - OFFSHORE MODEL  
EFI - FUEL INJECTION  
TR - TRACKER DECALS  
TRMM - TRACKER by MERCURY DECALS  
4-S - 4 STROKE  
BEL - BELGIAN-MADE for US MARKET  

For example, my 200 Black Max 2-stroke skeeter killer is a EXLPTO - electric start, XL leg (25"), Power Trim, Oil Injected.  If it was counter-rotating, it would be a CEXLPTO.  If you know the serial number, you can also call Mercury Marine customer assistance and they can tell you what the model is and what options were installed when the motor was built.  Mercury Marine's number is 920-929-5040.  You can ask a question online at:  http://www.mercurymarine.com/contact-us-online/  

Hope this helps - good luck!

[Aswaff400]

on mercury's if there is no sticker or other identification, there will be a small "L" stamped on the end of the prop shaft for left hand rotation, there will be no  markings if a right hand

[seabob4]

I knew there was something stamped on the end of the prop shaft...

Now that I think of it, it was OMC that stamped the "CR"...

My bad...