Questions for 4.3 6 OMC Cooling/Outdrive & HP

[111torrance111]

I trying to figure out exactly what I have for future reference and have a couple of questions.

Question #1:

I have a 1986 4.3 liter engine with a 2 barrel carb, how many HP is this motor?

Question # 2:

The motor was intermittenly overheating, this site recommened removing the termastat and try again. Removing this worked great, now I'll buy a replacement. The problem I have now is how do I refill the water level, I was told the engine uses fresh water for cooling and the raw water cools the fresh. Very confusing.

Question #3:

While checking the uper section of the outdrive I found milky looking oil, I assume water must be getting in somehow. I do hear a cluck when I put it in gear, but while in gear it runs fine. Now I don't want touse it until I get the oil/water problem fixed. While calling around for prices they want to what modle outdrive, I tell them it's an OMC800 but there looking for more information such as Cobra or another name. My outdrive has a gear on the outside to raise/lower, is there something I can look for to give me the coorect modle#

Sorry for running on, but this stuff can be confusing.

Jerry

 

[sundowner205]

Re: Questions for 4.3 6 OMC Cooling/Outdrive & HP

I believe that is an OMC 800 drive, from the "gear" that you refer to.

 

[Gary H NC]

Re: Questions for 4.3 6 OMC Cooling/Outdrive & HP

Cobra drives never had that gear...you have a Stringer drive..( Pre Cobra)
I bet the drive and engine was a 1985 although the boat is a 1986.
Not uncommon for the factory to use a year prior engine-drive setup.

Thats a non-Vortec 4.3. I think the HP rating with a 2bbl carb is around
180hp.

Post the motor and drive serial numbers and a few of the guys may look it up.

Oh,and don't use it until the leak in the gearcase is fixed..

 

[180shabah]

Re: Questions for 4.3 6 OMC Cooling/Outdrive & HP

If you were able to tell the mechanic that it is an OMC 800, and he had no idea what you were talking about, then you need to find a different mechanic to do the work.

2bbl pre-vortec 4.3 makes about 155-160hp at the prop - more at the crank.

 

[111torrance111]

Re: Questions for 4.3 6 OMC Cooling/Outdrive & HP

Thanks group,

Now what about the cooling question, does this motor use both raw (I'm assuming this means salt water) & fresh water to cool the engine? If yes I don't see where fresh water can be added or checked.


Jerry

 

[180shabah]

Re: Questions for 4.3 6 OMC Cooling/Outdrive & HP

Could be either raw ro fresh water cooled, they came both ways. Is there a heat exchanger? If not it is a simple RWC system. If you have doubts, post a picture.