Mercruiser 4.3 lh

A

Aquatron

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Alright I have a great deal on a 98 4.3LH serial number L651817.

So if I swap it with my 4.3lx right handed rotation. Besides swapping my drive to 1.81 ratio and lh how much other work is involved?

What would be the real advantage to change to LH from RH?

I guess one of my real issues why did mercruiser make a LH rotation motor.

Thanks for any insight......
 
gm280

gm280

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Re: Mercruiser 4.3 lh

Not seriously knowing for sure but could it be to conteract the RH torque pull on twin setups?
 
cr2k

cr2k

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Re: Mercruiser 4.3 lh

You would also need to get a RH drive out drive.
 
A

Aquatron

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Re: Mercruiser 4.3 lh

I have a 95 4.3lx serial number F597042.

What is getting me on the newer flame arrest its states left hand rotation. I have never seen that before. The other thing was the 4.3 LH.
I assumed the LH at the end represented something different then my LX. Once again assuming is trouble.

My out drive is 1.84r....
 
Bt Doctur

Bt Doctur

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Re: Mercruiser 4.3 lh

Not sure what your asking. 4,3 is 4.3 , no need to change gears, 4.3 was never made for right hand rotation .(rotation is viewed looking at the flywheel). And if this is a twin installation all you need is the counter rotating lower unit.
 
A

Aquatron

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Re: Mercruiser 4.3 lh

That's great news just a little confused.

What was throwing me was the 4.3lh.

I want to make sure I understand so I can use my 1.84 stern drive?

Thanks for the insight...,
 
achris

achris

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Re: Mercruiser 4.3 lh

The 'LH' is just a model designator, nothing whatsoever to do with rotation.

The 4.3LH was a vortec engine with a 4bbl carb. They couldn't call it LX because that had already been used for the non-vortec 4 bbl....
The 'H' is for high output.

Chris......
 
A

Aquatron

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Re: Mercruiser 4.3 lh

Thanks for the info.

Mercruiser has so many different models and then you see LH you start to wonder.

Plus having trouble locating info on Serial number. If you or someone has a good link to crossing s/n to specs that would be great.

If I a good link I would stop with these stupid questions.

Thanks again...,,
 
Fun Times

Fun Times

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Re: Mercruiser 4.3 lh

Aquatron said:
If you or someone has a good link to crossing s/n to specs that would be great.

If I a good link I would stop with these stupid questions.

Thanks again...,,
Click to expand...
No question is considered stupid here at iboats.;):)

Parts catalog link for S.N #0L651817, http://www.mercruiserparts.com/sele...br=4.3LH++(GEN++)+(4+BBL.)++++GM+262+V-6+1998

Parts catalog link for S.N #0F597042, http://www.mercruiserparts.com/sele...3LX++(GEN+II)+(4+BBL.)+++GM+262+V-6+1993-1995

Yes you can use your 1.84 stern drive.
 
A

Aquatron

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Re: Mercruiser 4.3 lh

Thanks for the links fun times.

Thanks all for all the great info....
 
Fun Times

Fun Times

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Re: Mercruiser 4.3 lh

Forgot to mention, Serial No: 0L651817 shows this engine came with the one piece exhaust system from new. MERCRUISER 1 PC W/PS 4.3L ALPHA

If the one piece exhaust is still mounted on the engine, Bear in mind Merc had a few problems with this style exhaust system that could ruin your engine much sooner then the standard two piece exhaust system. They recommend installing new two piece vs having/keeping the one piece that is no longer available by Mercruiser.

Try a search using "Batwings" for additional information. Batwings became their nickname.
 
A

Aquatron

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Re: Mercruiser 4.3 lh

Yes, it does have one piece manifold and they are coming off regardless at how good they look.

They will be retired to the scrap yard.......

Thanks again.....
 
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