120 vs 165 drive coupler

starsnstripers

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I have a coupler from a 120 merc I/O can it be used on a 165 l6 merc ? It's the same spline but the coupler itself is a smaller Dia. I think the bolt pattern is the same to. So, is it to light duty for an L6 165 or? thanks
 

starsnstripers

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Re: 120 vs 165 drive coupler

All the 120/140 part#s i look up are the same as the 165 L6 #76850A2 but this parts boat i got has a smaller Diameter coupler L4 120 Can it be used? Havent dismanteled yet are the flywheel bolt patterns the same? Thanks, any info on thi little coupler would be appreciated. :)
 

Bondo

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Re: 120 vs 165 drive coupler

Ayuh,......

They Should be the Same,+ Interchangeable..........
 

ziggy

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Re: 120 vs 165 drive coupler

All the 120/140 part#s i look up are the same as the 165 L6 #76850A2 but this parts boat i got has a smaller Diameter coupler
to me, that seems to be a conflickting statement..... if the part number is the same, the parts should be identical and interchangeable....... but you apperently have 2 different looking parts. how can that be unless you in fact have 2 different parts.... one of them must not be a 76850A2 unless there was a physical change in the part at merc w/o a part number change, and that i find hard to believe with all the part number changes that mfgs do with parts to confuse us.... just my uneducated guess......
 

starsnstripers

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Re: 120 vs 165 drive coupler

I'll get the dimentions in a little while I know the splines the same and it came off a L-4 120. I'll need to check the bolt pattern on flywheel too, that may be the difference. If the crank to flywheel bolt pattern are different between the L-6/L4, i'm not sure yet going to remove it here in about a half hour. The O.D. of the coupler is definetly smaller. Same shape, design, and spline though. Will be back in a bit thanks.
 

starsnstripers

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Re: 120 vs 165 drive coupler

Yes, here they are and yes the bolt patterns are the same. The splines are in great shape, should i use it on my L-6? thanks
 

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Bondo

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Re: 120 vs 165 drive coupler

If the crank to flywheel bolt pattern are different between the L-6/L4,

Ayuh,........

I believe you'll find that there are only 2 crankshaft bolt patterns on All of the Chevies that We use in boats,......

3, 1/4" for the 2 piece main motors,+ the 3" pattern for the 1 piece main motors......


edit;.... You posted as I was 1 finger typing,......:D

If the depth,+ distance of the splines are the same,....
I see no reason Not to run it......
 

captk

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Re: 120 vs 165 drive coupler

As I recall, All GM couplings were the same. Fords used a different bolt pattern. The u joint shafts were different between the inlines and the V-8s, but not the engine coupling. Until they went to the flex plate style.
 

starsnstripers

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Re: 120 vs 165 drive coupler

Why do i get all the strange stuff? haha! Anyway this small coupler came off a mercruiser L-4. And Bondo, Everything seems the same except for the overall diameter. HUH? wonder what the part# is? I guess i'll go for it unless anyone on here has any more info on this small Dia. coupler. thankyou! ;)
 

Bondo

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Re: 120 vs 165 drive coupler

HUH? wonder what the part# is? I guess i'll go for it unless anyone on here has any more info on this small Dia. coupler.

Ayuh,.......

It's a Very Rare Antique coupler from the very 1st Mercruiser,........:D

If the Splines are Better,+ Square'r,.......

Go for it,+ Run It........;)
 

starsnstripers

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Re: 120 vs 165 drive coupler

It came from a newer setup than mine haha! Yeah it looks good and fits the spline nice and snug. Will swap it out tomorrow and use it. Thankyou! :)
 

BUMP

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Re: 120 vs 165 drive coupler

I wish i had your problem......:rolleyes:




Helpful bunch of fellas, thanks to you all!
 
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