my first omc 400 sterndrive (1979) need good advice before first run.

jjacobs007

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I just traded my boat for a 1979 seaswirl with a 120, omc 400 outdrive, I have noticed theres many filling screws and such on it,and was wondering if the outdrive has to be all the way down to run boat? or can I trim up over shallow water while running? or will it mess up the ball things? thank you omc fans.
 

southkogs

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LOL ... the "ball things." I may have to go change that on the pages in my manual :D

Drive should be all the way down when you run. If you're under 700 RPM, you can tilt up for a shallow water drive but don't do much more than make steerage. Trim was a separate system on the Stringers usually on the front engine mount. Some units had it and some didn't.
 

jjacobs007

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LOL ... the "ball things." I may have to go change that on the pages in my manual :D

Drive should be all the way down when you run. If you're under 700 RPM, you can tilt up for a shallow water drive but don't do much more than make steerage. Trim was a separate system on the Stringers usually on the front engine mount. Some units had it and some didn't.

Yes, I renamed them ha ha !! I am also hearing a whirling noise from outdrive when I first start it and goes away after 5 min, and totally goes away when its in reverse, any ideas about that?
 

southkogs

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Make sure all of your gear cases have lube (that's my first thought anyway). You have three - lower unit, upper unit and intermediate.
 

markboutros

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i would automatically change all 3 of those oils, if its an electric shift the lower unit needs TYPE C oil ONLY
 

jjacobs007

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checked all fluids and there full and clean, there one grease gun fitting on it that faces the drain hole on boat that im grinding down my adapter so it will slide in and reach the fitting,but the plug is missing and theres been water in there for shure. and yes its an electric shift, what is c oil? I cant use regular lower lube? I will give pics if anyone likes to see.
 

southkogs

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...I will give pics if anyone likes to see.
Yeah, put some pictures up. '77 was the last year for the electric shift. '79 should be hydro-mechanical. Electric shift wasn't ever called a 400 to my knowledge. Type C oil is a thinner blend (kind of like transmission fluid if I've got things right) particularly suited for the springs and coils of the electric shift units.

If yours is hydro-mechanical any gear lube will really do.
 

vinnie1234

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If it is a 400, it should have a sticker on the top that says so. Why do you say it is an electric shift? It is possible that someone changed the drive on you, but you really should figure that one out. The electric shift (I think) is engaged forward gear with no power, neutral and reverse are powered by 2 solenoids and the "cable" going into the outdrive is actually a couple of wires.

I'm with the other guys in that; change out your gear oil, but make sure you use the right stuff. The electric shift is finicky (so I hear).
 

jjacobs007

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If it is a 400, it should have a sticker on the top that says so. Why do you say it is an electric shift? It is possible that someone changed the drive on you, but you really should figure that one out. The electric shift (I think) is engaged forward gear with no power, neutral and reverse are powered by 2 solenoids and the "cable" going into the outdrive is actually a couple of wires.

I'm with the other guys in that; change out your gear oil, but make sure you use the right stuff. The electric shift is finicky (so I hear).



It has the 400 sticker on top, and has wires going to lower unit that tells me its the electric shift. When its turned off and in neutral the prop spins freely. thanks for your help....
 

southkogs

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Last year for electric shift was '77. The 400 stern drive was after the Electric Shift. They are not the same thing. Now if you have shift wires that go down the port side of your engine and through the intermediate, then it's likely electric shift but not a 400. If you've got thru-hub exhaust you're not electric shift.

Pictures would probably be the best thing.
 

jjacobs007

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seaswirl boat 002.JPG
Last year for electric shift was '77. The 400 stern drive was after the Electric Shift. They are not the same thing. Now if you have shift wires that go down the port side of your engine and through the intermediate, then it's likely electric shift but not a 400. If you've got thru-hub exhaust you're not electric shift.

Pictures would probably be the best thing.

here some pics...
 
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southkogs

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Not electric shift. I don't know if you're hydro-mechanical or full mechanical, but you're not electric shift.
 

jjacobs007

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Well I know its not full mechanical, as theres no shift cable, but it does has a pair of wires running to the lower unit and that's all. let me trim it up and show wires on next pic. The manual says its electromatic.
 
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southkogs

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I think you're a hydro-mechanical shift - at which point I'm more than worthless to ya'. It's not the electric shift, but I'm not sure it doesn't use some electricity. I don't think you need Type C in your lower, but I'm not 100% sure of that.
 

jjacobs007

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Thanks kogs for helping me.. It runs good just trying to figure all this stuff out.
 
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