78 OMC 800 Stringer outdrive

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I am trying to find out the correct oil to use for this outdrive and the correct method for making sure the lower drive is full..... Each drive has a lower & upper plug.

 

[Howard Sterndrive]

Re: 78 OMC 800 Stringer outdrive

80W90 - like most any outdrive : fill from the bottom until oil floods out the top port. install top screw, remove squeeze bottle or gear lube pump and quickly replace bottom plug (makes a little mess- not much)

you have 4 housings to check and/or fill - the lower unit, upper unit, intermediate housing, and the tilt clutch

(tilt actually calls for 30wt, but 80W90 fine in there too)

 

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Re: 78 OMC 800 Stringer outdrive

Thx for the quick reply Howard.

I have found all 8 of the drain and fill plugs. The upper unit has a little dip stick so I imagine I just fill to the line? The lower unit I wasn't sure about. I drained it & very little came out so thx for clearing that up for me.

The only plug I am have trouble with is the top plug on the intermediate housing. I have the lower one loose but the top one is tight. The metal is very soft & I can feel it wanting to strip. I've tried a large screwdriver & vise grips but the metal was starting to twist. Next I figured to use an impact screwdriver & large bit. I imagine this will either loosen it or totally twist out the metal out.

If you have any advise in this area before I use a impact driver on it, it would be much appreciated...

 

[Howard Sterndrive]

Re: 78 OMC 800 Stringer outdrive

terminology is a bit backwards...that's the "upper" you have the tight screw in, intermediate is the housing bolted to the engine (yeah, it's kinda backwards...but that's omc)

yes, fill the intermediate until it's running out the dipstick hole at the top with the boat fairly level

impact driver is fine for a tight plug.

a very common repair on those uppers if the plug strips, is to use a 3/8 stainless header bolt with the mercruiser washer/gasket. Instead of grabbing 5/16" of thread length, a header bolt will grab about a full inch - that thread runs deep and can be tapped deeper. The mercruiser fiber gasket washers (191833 i think is the number) fit right on the bolt perfect.

 

[superbenk]

Re: 78 OMC 800 Stringer outdrive

Aren't you supposed to fill the upper case from the top instead of the bottom? I've always done it from the bottom, but have a horrible time with bubbles & over-filling the upper. Filling from the top is super slow though. Haven't really found the best way to do the upper.

 

[Howard Sterndrive]

Re: 78 OMC 800 Stringer outdrive

I pump it in the bottom until it pukes out the top hole and makes a huge mess, then I put both plugs in. I check it next day and probably after the next run.
I don't see how anyone could get lube in the top... the hole through that steering trunnion is just a hair bigger than the dipstick... no room for air to burp out past the incoming oil.

 

[superbenk]

Re: 78 OMC 800 Stringer outdrive

I pump it in the bottom until it pukes out the top hole and makes a huge mess, then I put both plugs in. I check it next day and probably after the next run.
I don't see how anyone could get lube in the top... the hole through that steering trunnion is just a hair bigger than the dipstick... no room for air to burp out past the incoming oil.

I do that too, but I've had it come out the dip stick when I loosen it due to trapped air that wants to burp out even after sitting. Usually happens when its hot out. Maybe I need to let it settle with the dipstick loose for longer after filling so all the air can escape.

I guess anyway you do it it gets messy.

 

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Re: 78 OMC 800 Stringer outdrive

Thx 4 all the help....

Of course the only tool I forgot to bring home today was my impact driver but I did bring a good screwdriver and with some luck I got the plug loose. The oil out of the intermediate drive & lower drive look ok, still brown. The upper drive oil was black so I'm sure thats not good.

The intermediate & upper drives both took 1/2 a quart of gear oil. The lower drive took a qt and I still can't get oil to come out the top plug so I'll have to get another qt tomorrow....

Do those amounts sound right?

I ran it real quick just to see what the upper drive sounded like.....I'm getting a little bearing noise so I'm guessing I will be learning how to but bearing in that real soon...

 

[superbenk]

Re: 78 OMC 800 Stringer outdrive

I'd recommend draining and refilling all 3 cases with fresh oil. Doesn't sound like you know what you have nor does it sound at all fresh. Full oil change ensures you're running with clean oil & you'll be able to spot any real problems faster.

 

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Re: 78 OMC 800 Stringer outdrive

Hey SB thx 4 the reply.

You are correct that I have never worked on any outdrives before. That is what I wanted to do before I put it in the water is to change all the fluids & gas.
So far I've changed the oil & filter, plugs in the engine. cleaned out the carb & set the points. put in a new starter. I went with a cheapy automotive one just to get it running and make sure there isn't some serious drivetrain problems. Once all is good I'll spring for a marine duty one..

I drained all 3 of the drives, the intermediate drive and lower drive had brown gear oil in them which didn't look to bad but the upper one had black gear oil drain out of it and that worries me.

I filled all 3 drives from the bottom plugs. The only one with a dipstick was the upper drive and it's real tough to tell if the level is right but I have a 1/2 qt in it right now. The intermediate drive took about a 1/2 a qt before oil started coming out of the top plug and that level looks good. I got a whole qt in the lower drive but still nothing coming out of the top plug yet...

Could you tell me what the capacities of the drives are? I just don't want to run it if I'm low on oil....

Thx 4 all the help

Brian

 

[superbenk]

Re: 78 OMC 800 Stringer outdrive

I don't have capacities handy, sorry. Solec manual has them & can be found for download online w/ some digging.

That automotive starter will get you in trouble with CG if they catch you & it's dangerous. Marine starters aren't heavier duty than automotive ones, they're sealed from sparks so you don't ignite gas fumes that settle in your bilge & blow you or your boat to kingdom come. You should not be running automotive parts in a boat. Period.

 

[run2car]

Re: 78 OMC 800 Stringer outdrive

Capacities:

Upper- 13.5 oz
Lower- 33.8 oz
Intermediate- 6.25 oz

Note: 240, 250 and 260 HP lowes take 38.4 oz's

 

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Re: 78 OMC 800 Stringer outdrive

Capacities:

Upper- 13.5 oz
Lower- 33.8 oz
Intermediate- 6.25 oz

Note: 240, 250 and 260 HP lowes take 38.4 oz's

Thank you for the info