View Full Version : Lower gear case help

05-29-2005, 12:47 PM
The manual for my 1984 OMC tells me that I should use OMC Premium blend gear case lube with an electric shift unit. How can I tell if I have an electric shift unit and how were can I get an approved oil now that OMC is out of business?

Thanks for all the help

05-29-2005, 03:31 PM
I used to have an electric shift OMC.
I eventually went with regular 80W-90 in the lower gear case.
When I pressed some OMC repair people, they told me the thinner electric shift oil was important if the water was cold like 40 degrees.
Warm water would not be a problem and it was not, the gear engaged disengaged just fine.
This is just my own experience.
I have rebuilt several lower electric shifts. There is a large square profile engagement spring that wraps around a hub when energized by an electromagnet. This spring winds up tight on the 3" diameter hub and this is what is engaged, locking the input gear hub to the propellor shaft, there is no gear cog engagement. there is a forward spring facing one way and a reverse spring facing the other. You could probably even use a heavy 50 weight engine oil. I tried the 80W gear oil and never had it slip.

05-29-2005, 03:38 PM
All OMC stringer cases were electric shift.
And these were all pre OMC cobra. I think Cobra started in the 80's and I think these were not electric shift. But I am not sure.
There is a thick rubber wire entering the housing on the port side of the motor. I know the electric shifts all had electric push buttons switches for forward and reverse on the OMC control throttle. And on mine it said OMC Electric Shift.

Steve Hornsby
05-30-2005, 11:50 AM

This is what I understand from my own experience - get some serious advice from your local pros.

OMC electric shifts required OMC "type C" oil. This is now called OMC Premium Blend.

If your drive is manual shift, you can use OMC Hi Vis or OMC HPF synthetic. All these products are readily available at my marina.

Now to the drive. I had an 1984 OMC drive - it was the 800 series. There was also a 400 series for the 4 cylinders. I beleive these had a short run of 2 to 3 years. These were manual shift and can use Hi-Vis or HPF.

The drive before these (last in 82 I think) were commonly referred to as the stringer drives. As stated in the above post, and as per my thoughts, I am sure these were electric.

I believe Cobras arrived in 85. I have an 89 and use HPF exclusively.

If your drive is electric, it will need the special oil to function properly.

Hope this provides some CLUES. I hope someone at your local can provide you with the absolutely correct advice.