Questions about my Mercruiser 4.3

[Bates7985]

New Boater here! Looking for Information on my 4.3. Just purchased a 94 Monterey 190 SCR with a 4.3 LX ( SN 0F148067) with 330 hrs. After speaking to Mercruiser the engine was manufactured in 93. But it has Vortec valve Covers, an 8 bolt intake manifold and a ribbed aluminum oil pan. Didn’t the 93s have the 12 bolt intake manifold? I could be wrong. Ultimately I’m trying to figure out if this is a mismatched SN or if it’s an actual Vortec motor. How do you tell the difference. This boat at WOT did 53 mph on the water with GPS. Which seems fast for a regular 4.3. Any insight on this would be greatly appreciated. Thanks.

 

[Rick Stephens]

Vortec head engines hit Merc in '96. Someone must of swapped out the heads and intake on your motor. That's a good thing. Your block is obviously not originally a Vortec as it has v-belt accessories.

 

[Rick Stephens]

Note, I have virtually the same setup. A '93 block with Vortec top end. A frankenmotor. Have to use multiple manuals to work on it.

 

[Bondo]

New Boater here! Looking for Information on my 4.3. Just purchased a 94 Monterey 190 SCR with a 4.3 LX ( SN 0F148067) with 330 hrs. After speaking to Mercruiser the engine was manufactured in 93. But it has Vortec valve Covers, an 8 bolt intake manifold and a ribbed aluminum oil pan. Didn’t the 93s have the 12 bolt intake manifold? I could be wrong. Ultimately I’m trying to figure out if this is a mismatched SN or if it’s an actual Vortec motor. How do you tell the difference. This boat at WOT did 53 mph on the water with GPS. Which seems fast for a regular 4.3. Any insight on this would be greatly appreciated. Thanks.

Ayuh,..... Welcome Aboard,.... The serial number is more important to replacin' all the accessory parts bolted onto the long block motor, than fixin' the long block,....

Sounds like somebody already did the Vortec head upgrade for ya,.....

 

[achris]

Your serial number does match up as 93, and you are correct that they weren't vortec engines, but they did have the word 'Vortec' on the rocker covers (very confusing, yes).

Don't know where you are or where the boat was, but didn't somewhere in the USA have some unusually cold weather (a couple of years ago) and a bunch of engines froze? It may be that this is a new long block with the old fruit and veg refitted (which would include the serial number tag)... Have a look down near the starter motor and see if the block serial number tag is still there...

It's not just a heads upgrade, you have an aluminium sump, so it was the whole long block.

Chris....

 

[Rick Stephens]

Your serial number does match up as 93, and you are correct that they weren't vortec engines, but they did have the word 'Vortec' on the rocker covers (very confusing, yes).

Don't know where you are or where the boat was, but didn't somewhere in the USA have some unusually cold weather (a couple of years ago) and a bunch of engines froze? It may be that this is a new long block with the old fruit and veg refitted (which would include the serial number tag)... Have a look down near the starter motor and see if the block serial number tag is still there...

It's not just a heads upgrade, you have an aluminium sump, so it was the whole long block.

Chris....

From what I can see, he has a 93 block with v-belts. That means steel pan and timing chain cover. Good combo - and no balance shaft either. Needs fluid motor mounts though.

 

[achris]

From what I can see, he has a 93 block with v-belts. That means steel pan and timing chain cover. Good combo - and no balance shaft either. Needs fluid motor mounts though.

In his opening post he says ...

... and a ribbed aluminum oil pan. ...

That serial number is a Gen II block (not to be confused with a Gen II drive ), and so has a balance shaft (it even says that on the carb cover in the 2nd photo) and 'solid' mounts.

... a 4.3 LX ( SN 0F148067) ....

So, if it is what I think it is (a new long block to replace a damaged original block with the original accessories fitted onto it), then it's likely it has an aluminium timing cover as well.

Chris.......

 

[Rick Stephens]

In his opening post he says ...


That serial number is a Gen II block (not to be confused with a Gen II drive ), and so has a balance shaft (it even says that on the carb cover in the 2nd photo) and 'solid' mounts.

View attachment 359195
So, if it is what I think it is (a new long block to replace a damaged original block with the original accessories fitted onto it), then it's likely it has an aluminium timing cover as well.

Chris.......

Yup. Nailed to the wall with my own ignorance