1972 Mercruiser 165.

Rranger

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Any other Mercruiser engines that if the 165 was removed would bolt up to the 165’s rigging? Looking at a boat with a failed 165.
 

ROY WILLIAMS

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Any other MerCruiser engines that if the 165 was removed would bolt up to the 165’s rigging? Looking at a boat with a failed 165.
model 165. 165HP,250CU.IN.,6 CYL PISTON, COMPRESSION PRESURE 140 PSI., PLUG AC-MR43-T, NO 6DEG BTDC YES 2DEG BTDC, ENGINE OIL 5QT,
 

Bt Doctur

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any GM inline 6 cylinder that has the 2 threaded holes to the left of the timing chain cover for the front motor mount.
poss replacements the in line 4 FWC mercruiser ,shorter than the 6, would need to fab up a new front stringer
then a v6 ,would need to fab up new front stringer motor mounts
drive gear ratio will work with all three 1.65-1
 

Scott Danforth

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I personally would drop in a 292 and fabricate a new motor mount if wanting to keep the original transom shield or outdrive.

a new 4.3 / A1G2 long-tail will drop in with minimal work to the transom and mounts

then again, a 5.7 or 6.2 / A1G2 long tail would also drop in (and still weigh less than the inline 6)
 

Scott06

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Any other Mercruiser engines that if the 165 was removed would bolt up to the 165’s rigging? Looking at a boat with a failed 165.
Nothing directly -a 3.0 is drop in most easily but will make less power.

A 3.0 is shorter so front motor mount will need to be moved back.

4.3 is probably the best if there is room in the engine compartment but will require glassing in side motor mounts. the 4.3 replaced the 165 in the merc line up in the mid 80's and makes similar or more power.

Is the 165 rebuildable?
 

kenny nunez

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Both 250 & 292 in line 6’s that came from a truck have the extended tab on the starboard side of the timing cover. A passenger car engine block will work after making an extension to the mount along side of the pan rail.
 

Rranger

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I appreciate the advice on here. Have a shot at a boat with two of these that are runners. Look pretty much identical to the 165 Merc?
 

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Scott06

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I appreciate the advice on here. Have a shot at a boat with two of these that are runners. Look pretty much identical to the 165 Merc?
yes looks like the OMC version of the same Chevy straight 6. They were made in a few displacements and HP over the years, but any of them would be drop in. if twins not sure if one may be reverse rotation, but look to have closed cooling which is good.

By the looks of the picture they do you have to take the whole boat or can you leave what you dont need ?
 

kenny nunez

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FW cooled engines are a safe bet. The OMC exhaust manifolds enter the exhaust down pipe the wrong way for Mercruiser. You will have to use the Mercruiser manifolds. You will have to swap the wiring harness and use the Mercruiser alternator With the bracket. The carburetor, fuel pump, circulating pump, coil & the distributor are the same. Good luck. The remainder of the OMC stern drive parts are hard to find so you may be able to sell off the remainder of the parts.
 

Rranger

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yes looks like the OMC version of the same Chevy straight 6. They were made in a few displacements and HP over the years, but any of them would be drop in. if twins not sure if one may be reverse rotation, but look to have closed cooling which is good.

By the looks of the picture they do you have to take the whole boat or can you leave what you dont need ?
I have to talk to the owner, he wants the boat removed and no trailer under it. I have a roadrunner that had a 19' Sangster on it might be able to limp it to a landfill. I'd rather a remove engines deal with him, but will see. And of course when were they last run and how good are they.
 

Rranger

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FW cooled engines are a safe bet. The OMC exhaust manifolds enter the exhaust down pipe the wrong way for Mercruiser. You will have to use the Mercruiser manifolds. You will have to swap the wiring harness and use the Mercruiser alternator With the bracket. The carburetor, fuel pump, circulating pump, coil & the distributor are the same. Good luck. The remainder of the OMC stern drive parts are hard to find so you may be able to sell off the remainder of the parts.
Thanks Kenny.
 

Scott06

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I have to talk to the owner, he wants the boat removed and no trailer under it. I have a roadrunner that had a 19' Sangster on it might be able to limp it to a landfill. I'd rather a remove engines deal with him, but will see. And of course when were they last run and how good are they.
I I figured it was haul it away or pay more if you leave what you dont want...

I would look to see if water got down the carbs as its likely they were not covered as long as it has been sitting
 

kenny nunez

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If they are stern drive engines you might have a problem separating them from the intermediate housing. Those particular models tended to rust the drive coupler to the shaft. If this happens I can walk you through the procedure to seperate them.
 

Scott06

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If they are stern drive engines you might have a problem separating them from the intermediate housing. Those particular models tended to rust the drive coupler to the shaft. If this happens I can walk you through the procedure to seperate them.
is this the procedure ...

 

Rranger

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Nothing directly -a 3.0 is drop in most easily but will make less power.

A 3.0 is shorter so front motor mount will need to be moved back.

4.3 is probably the best if there is room in the engine compartment but will require glassing in side motor mounts. the 4.3 replaced the 165 in the merc line up in the mid 80's and makes similar or more power.

Is the 165 rebuildable?
As in this one?
 

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bigblocksarefun

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My old Crestliner came with a completely seized 165 (250). Like my sig says, never accept a free boat. It was my uncle's, I remembered taking it out a few times in my late teens. I found a Merc 292 to drop in it's place, just needed to fab a taller cover since the 292 is a raised block. Actual marine Merc 292 came with a 4bbl.

2c20_1.jpg

You can always get a 292 long block and just put your 250 accessories on it. If memory serves the 292 was rated 200 hp even (don't quote me) and felt much torquier, which isn't surprising considering the longer stroke. Moved a 17.5' footer pretty well.
 
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