1992 4.3L w/ Alpha 1 - Motor oil & gear oil question

[df909]

I have a 1992 4.3L with an Alpha 1 Gen 2 drive. What viscosity motor oil should I use when I change it? Also, would using full synthetic help engine life much? I don't mind an extra few bucks once a year if it means more years of boat life.

I read the bottle on two Quicksilver gear oil bottles. Both bottles stated not to mix the premium with the other (I don't remember what it was called). Why is this? If I drain the gear oil from the drive and it happened to be the premium, and I put in the other one, will I mess anything up? The previous owner doesn't know what type of gear oil was used.

Thanks.

 

[45Auto]

Re: 1992 4.3L w/ Alpha 1 - Motor oil & gear oil question

Mercruiser engine oil recommendations below. If you don't like the factory recommendations, feel free to use whatever you like. Someone on the internet will support you .....

In the outdrive, use the Mercruiser High-Performance outdrive lube. It's a synthetic and has the capability of holding lots of water in suspension while still lubricating if your outdrive gets some water in it.

Don't worry about the little bit of mixing you'll get if you drain it completely then refill it. If it's half-empty and it doesn't have the High-Performance stuff in it, go ahead and drain it all the way before putting in the new stuff.

Check it for water and top it off every 6 months, change it once a year, and it'll be happy for a long time.

 

[df909]

Re: 1992 4.3L w/ Alpha 1 - Motor oil & gear oil question

Thanks for the help. I live in Southern California & there's no way I'll be in the boat at 30 degrees, so normal operating temp for me would be from about 50ish to 100ish. I was thinking of getting the Castrol High Mileage 20w-50w full synthetic as the motor is a 1992 and the hour meter isn't working. That sound like the motor should be happy?

I'll do exactly what you said for the drive as I suspected it wouldn't be a big deal to mix the little bit that was left over. What about using a friction reducing additive in the drive?

Thanks again- Dave.

 

[Fishermark]

Re: 1992 4.3L w/ Alpha 1 - Motor oil & gear oil question

What about using a friction reducing additive in the drive?

Just use the Mercruiser High-Performance outdrive lube - the green stuff. And don't worry about any other additives.

 

[ErieRon]

Re: 1992 4.3L w/ Alpha 1 - Motor oil & gear oil question

Ditto^^^...the synthetics have a friction reducing component.

 

[cr2k]

Re: 1992 4.3L w/ Alpha 1 - Motor oil & gear oil question

Your engine oil choice is perfect!