1979 Evinrude 4hp gear oil and cooling?

[BrianVT]

Model 4932D. Std. lower end (not weedless). My other lower ends have an oil vent and fill hole and I fill it from the bottom until it comes out the upper vent hole. This little guy only has one hole. Do you know what the procedure is? Does it take normal 80W-90 lube? I read some some of these may have used grease instead?
Also, how do I know if the cooling/impeller is working? There's no pee hole above the water line.

 

[racerone]

Hole in the gear case down to drain.----Hole up to fill.----Do not use grease !-----Install a new impeller if you do not know how old it is.-----Water spits out with exhaust relief at the back of exhaust housing.

 

[Crosbyman]

here is what CHAT GPT Said..

What you need​

• Marine gearcase lube (SAE 80/90, GL-4 or GL-5, specifically “outboard gear lube”)
• Gear lube pump or squeeze tube that fits the oil bottle
• Flathead screwdriver
• New gaskets for the drain/fill screws (very important, don’t reuse old ones)

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Steps to Refill​

1. Locate the plugs
   • On your motor, there are two screws on the gearcase:
     • Lower screw = drain/fill plug (bottom of skeg, side of the gearcase).
     • Upper screw = vent plug (a few inches above).
2. Drain old oil (if not already done)
   • Place a pan under the skeg.
   • Remove the lower screw first.
   • Then remove the upper screw (this lets it drain faster).
   • Inspect the oil:
     • Milky = water intrusion (check seals).
     • Metal shavings = gear wear.
3. Refill with new oil
   • Attach the pump or squeeze tube to the lower hole.
   • Pump in fresh oil from the bottom up until it starts coming out of the upper vent hole.
     (Filling from the bottom prevents air pockets.)
4. Seal it up
   • When oil just begins running out the upper hole, install the upper screw with a new gasket.
   • Quickly remove the pump/tube from the bottom and install the lower screw with a new gasket.
5. Wipe and check
   • Clean excess oil.
   • Run the engine in water briefly and check for leaks.

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Notes for Your 1979 4hp​

• Gear oil capacity is small (about 6–8 oz).
• Use OMC/BRP Hi-Vis gearcase lube or any modern marine SAE 80/90 gear lube.
• Always replace screw gaskets — they’re cheap, and reusing old ones is the #1 cause of water intrusion.

 

[racerone]

It was stated that there is only 1 screw on this gearcase !!----Same gearcase as was used on earlier 2 HP motors.

 

[Crosbyman]

yep. blame Chat GPT....still learning