Re: Lightwin lower unit lube and maint. ?
Hello, just a quick question on lower unit maint. for my '56 Lightwin. My motor says to use Hypoid oil, my manual say use "OMC Type B" lubricant. I used 80W-90 marine lower unit lube I got at walmart, is this what I should be useing ? Next, after draining I laid the unit on it's side with the upper plug hole raise slightly. I squezzed the lube in from the bottom hole until it poured out the top. Then put the lower plug in , then the upper plug. Was that the correct procedure ? By the way, are the LU gears made of stainless steel ?
-Thanks
You have to go back in history for the answer. When OMC first started using oil instead of grease, they used "Hypoid Oil", which is an oil developed for Hypoid axles on automobiles and available everywhere. Then OMC saw some potential profit escaping and decided to package and sell their own oil. They called it OMC Type B, and said to use it wherever Hypoid was specified. Then OMC changed the formula and called it Type C, and said to use it wherever Hypoid or B was specified. Then it became "Premium Blend" with another formula change. Now its "Hi-Vis".
Anyhoo, Hypoid Oil was 90 weight oil with additives. Nowadays they just call it 90 weight gear oil. Companies package it up in tubes with a slightly modified viscosity index and call it 80-90 Outboard gear oil. The additives include anti-wear, anti-foam, anti-water/rust, and so on. You just have to trust them as to what is actually in there because there are no established rules. And yes, it is the correct oil for your Lightwin. Unless you want to go to a dealer and get some Hi-Vis.
The motor is supposed to be standing upright to fill. Otherwise your procedure was correct. You can fix it by standing it upright and remove the upper plug. If it is overfilled, it will overflow out till it is the right level.
The gears are hardened steel. The shafts are stainless steel. The bearings are bronze bushings.
EDIT: BTW, a bit of little-known trivia: One of those older OMC formulas contained a whale oil additive. But then whale hunting was outlawed and OMC had to change the formula and name. I forget which one had the whale oil though. But I hoarded one of the last five gallon cans for my own use.
