Mercruiser 165 inline 6 timing marks - reverse rotation engine?

[billinkansas]

I have a Mercruiser 165 inline 6 engine that I bought from someone who started to convert it to a truck motor. The notched timing indicator on the timing chain cover is on the alternator side, the left side viewed from the back of the engine. The normal place is on the other side, from other engines that I've seen. The timing cover appears to be Mercruiser black. I do not have the serial number of the engine, but it would be early 1970's, since it has the red sticker about leaded fuel on the valve cover.

Do I somehow have a reverse rotation engine? I do have a complete semi derelict engine that I could rob parts from if needed.

Thanks in advance!

 

[Bt Doctur]

truck motors are standard left hand viewed from the fly wheel, your 165 is left hand also

 

[Bondo]

Ayuh,..... Merc has never put a righthanded motor in front of an I/O,.....

 

[billinkansas]

Thanks for the replies. I am not sure that this engine was in front of an I/O. Merc did build an inboard version righthanded, I believe. Ebasicpower site has the LH and RH firing order diagram.
Anyhow, I did some part number digging and found a timing cover that looks like this one with the indicator on the exhaust side of the engine. It is part # 59341A. I'm pretty sure that I'm going to be ok.

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[achris]

... Merc did build an inboard version righthanded, I believe. ..

No inline 6 inboard engine produced by Merc. Inboard 4s and V8s, yes... But not an inline 6... If that was a Mercruiser engine, it was an I/O, and they are ALL left hand. Understand how the shift system in a gear housing works and you'd understand why you can't put a right hand engine in front of a Merc I/O... Merc DOES produce counter-rotate stern drives, but that's done in the drive, not by turning the engine backwards.

Chris....

 

[440roadrunner]

Use a piston stop to verify TDC. If engine is "automotive" rotation, the advance marks will be "as the balancer is coming up to" TDC IE viewing the front, the advance marks will be CCW of TDC

If there is ANY chance this is actually reverse rotation, the oil slinger serrations on the crank will be backwards and "it will always" leak a bit of oil from the main seal

 

[Chris from Canada]

I may be a pain in the ass to turn the motor with a socket and ratchet (many 250 CIDs don‘t have a crank bolt on the harmonic balancer. But it’s super easy to figure it out. Pull the valve cover, and turn the motor in the direction that has the exhaust valve closing just as the intake valve starts to open. The motor will have some valve overlap. The exhaust valve is open for the exhaust stroke (piston coming up) and before TDCE (Top Dead Centre Exhaust) the intake valve will start to open. Hope this helps

Chris

 

[Bt Doctur]

you do not have reverse rotation