Problem: Changing Gear Lube

[Jim McC]

I cannot loosen the 2 screws to change my gear lube. They just won't budge. It's a 25 HP Johnson. Any ideas? I'm trying to avoid taking it in to the shop. Thanks.

[Fishing Rhino]

It cannot be big bucks to get the lower unit lube changed. BPS is going to winterize my motor (150hp Merc) in November. They change gear oil, the fuel filter, check the water pump and impeller, grease all the pivot points, check the spark plugs, treat the fuel that remains in the tank. (I put marine StaBil in every time I add fuel) They also fog the engine.

Total cost for parts and labor: 139 dollars. That does not include any parts for the water pump that may be needed.

You don't say how old your Johnson is, or when the gear oil was last changed. The threads should not be seized. They are not tapered pipe threads. An "O" ring seals (or used to the last time I had an outboard several years ago) the oil in, and water out. So the threads should have lube on them.

Way2slow is the man who can answer your question. My advice is don't do something that might cause damage and end up with a problem that will cost big bucks to fix.

[Way2slow]

Get you an impact driver. If you have a Harbor Frieght close by, they have them for about $10 http://www.harborfreight.com/impact-screwdriver-set-with-case-37530.html. These are very poor quality but should be able to get your plugs out. Sears and others will have one also but you will pay more for the better quality.

They usually have a nylon washer under the heads, but I've seen some with and O-ring. Usually someone has rounded the screw slots on the screw so your screw driver won't hold the edges. If this is the case. I would recommend getting new plugs and seals to go back in. I have seem them so screw up by the wrong screw driver, I've had to drill the the centers and then drill the heads off. Not very much fun when you realize the housing could be junk if you screw up.

[Jim McC]

The motor is a 1992, and I changed the lube 2 seasons ago. I tried last fall also, and couldn't loosen the screws. So you put the impact driver with bit on the screw and hit it with a hammer? Is this very risky to the lower unit? Thanks.

[Fishing Rhino]

You put it into the screw's slot, apply counterclockwise pressure, and the handle will back out a bit. Then you hit it with the hammer.

It is designed to "shock" the screw loose while keeping the driver bit firmly in the slot.

The question is, how hard do you hit it? Maybe an impact gun/driver like they use to remove and apply lug nuts on wheels would be less likely to damage the housing, and therefore safer in inexperienced hands. I'd be surprised if they didn't have screwdriver bits for them.

Check with the place where you buy tires or have your vehicle serviced. They may be willing to help you out for a few bucks.

Again, Way2slow will know better than I if the impact gun/driver is a practical alternative, or how hard you can hit the impact driver with a hammer.

I've used these tools in my past. It's just that the thought of hammering on my lower unit would make me nervous.

[Way2slow]

You put it on the screw, hold pressure on it with one hand like you're trying to loosen the screw and and give it a firm lick on the head with a 2 - 3 pound hammer. It's not like you're trying to drive the thing through the LU, just a few firm hits. That LU is pretty tough, you are not going to hurt it unless you start beating on it with full swings.

By the way, you should change your LU lube every year. When you are through fishing because of winter is a good time to do a complete service on the motor, pull plugs out of carbs and drain them, use compressed air and purge the fuel lines. Add some SeaFoam to gas in tank or pump that gas out. Even with SeaFoam, I would not run it the next season, and if stored outside where the sun will shine on it, fog the motor. Under the cowl of the motor will look like you turned a water hose on it when the morning sun shines on it. You should change the water pump/impeller at least every three - four years. Put the batteries on a maintainer, and pack the trailer wheel bearings.

[quanjig]

Try an electric screw gun. They usually have torque settings. Start off very low and increase the setting. Should be able to "bump" the screws loose that way

[Jim McC]

Thanks guys.

[J Francho]

PB Blaster and an impact driver. I remember the old Evinrude on the '62 Penn Yan being a PITA.

[freebie]

impact driver. hit it till the screw starts to move. I would recommend new seals also while your in there. omc part number is 311598. bag of 5 is like $10. when you refill it make sure you pump it up from the bottom hole.