Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

[Kmw777]

We tried to drain the lower unit gear oil in our 25 HP 1991 johnson (to store for winter). There were 2 screws at the bottom where you "drain" it. We could not get the large flat standard screw out and there was another one right next to it with a phillips head. We were able to remove this phillips head one but cannot get it back in. It seems to have a pin like shaft at the end like it has to hit a special hole before the screw part of it grabs? How do we get this small screw back in?

Thanks

Kmw

 

[hardwater fisherman]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

the phillips screw is not a drain screw. it is the pivot pin for your shifter lever. the flat head beside and the one flat head higher up on the gearcase are the drain screws. maybe someone here can tell you how to reinstall the pin. i am not sure how on that type of gearcase. it is easier on mine because the very bottom portion comes off.

 

[bonzoscott]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

It's unfortunate that you took the phillips screw out. Lower unit has to come off to get it back together. As far as the Stainless drain and fill screws - use a large screwdriver that fits the slot in the screw well. And use a screw driver that has a square shaft. Mine is 5/16. Then, while holding firm pressure on the screwdriver to screw, use the 5/16 wrench on the shaft of the screwdriver. Better yet, purchase a Manual Impact Driver. ~$20 at most places including Harbor Freight.

 

[Roberthill]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

Did the same thing once but I did get screw back in I tilted motor up as it was on boat and got a flashlight and a scribe and positioned shifter lever where the hole was lined up with the scribe and put the screw in .

 

[likitvi]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

I changed the drain plugs to new with hexagon key. Last time I tried to open them, the key slot went round (sic.) and the hexagon driver just spinned freely in the plug. Had to drill through the plug to remove it with an ez-out, breaking 3 of them and 1 handle in the process. Suppose I over-tightened them.

 

[bonzoscott]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

Suppose I over-tightened them.

Do not want to over tighten. You'll pull the threads right out. OP - don't use the Manual Impact Driver to re-install.

 

[EZSteury]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

I did this on My 35hp evinrude, I did not know about the screw and I'm just to curious to leave it alone. If You pull the lower drain screw You can use a pick or small flat screw driver to lift the lever back to where You can re-install the screw.Not easy but if You pull it and our motors are similar You see what I'm talking about.

 

[daselbee]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

You messed up big time. That screw is the pivot pin for the shifting mechanism deep in the gearcase. You might get lucky probing around thru the hole, while moving the shift rod ever so slightly. More than likely the gearcase will have to come off, the water pump wil have to come off, the shift rod upper housing will need to be un-bolted and raised way up on the shift rod so you can see down into the gearcase and re-insert the screw. You best be very careful. If you pull the shift mechanism up and out of the yoke it connects to, you will most likely have to pull the propshaft to fix it.

 

[Vic.S]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

We tried to drain the lower unit gear oil in our 25 HP 1991 johnson (to store for winter). There were 2 screws at the bottom where you "drain" it. We could not get the large flat standard screw out and there was another one right next to it with a phillips head. We were able to remove this phillips head one but cannot get it back in. It seems to have a pin like shaft at the end like it has to hit a special hole before the screw part of it grabs? How do we get this small screw back in?

Thanks

Kmw

If you are lucky someone like Joe Reeves will be along and will tell you how you might get it back in and locate in the shift lever correctly.

I have seen a method described but dont remember it.

Dont hold your breath though and dont shake it about or operate the gear shift while you are waiting.

 

[doityourself]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

I changed the drain plugs to new with hexagon key. Last time I tried to open them, the key slot went round (sic.) and the hexagon driver just spinned freely in the plug. Had to drill through the plug to remove it with an ez-out, breaking 3 of them and 1 handle in the process. Suppose I over-tightened them.

I replaced my plugs with new hex key ones too. Don't! I managed to break off the Allen wrench in it and had to create a screwdriver slot with a cut-off wheel to remove the plug. Back to the slotted plugs now. Does anyone know where to find them at a reasonable cost?

 

[boobie]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

The torque spec for the drain plug screws is 84 inch pds.

 

[Tim Frank]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

That's why you so often see in here the variation on "RTFM"....i.e. "BTFM"
B = Buy

Real time and $$ saver.

 

[bonzoscott]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

That's why you so often see in here the variation on "RTFM"....i.e. "BTFM"
B = Buy

Real time and $$ saver.

I'm gonna guess and say - Refer to Factory Manual & Buy THE Factory Manual... Lol

 

[Tim Frank]

Re: Lower Unit gear oil screws (2 of them) 1991 Johnson 25 HP

Yessir.

 

[b.lee]

Bringing this one back from the dead,
I recently purchased a pontoon with a 1992 25hp Evinrude.

Well, I loosened the phillips screw near the flat head drain plug on the lower unit. I loosened it just enough for a little gear lube to drip out, then re-tightened it. It tightened up as normal, no issues.

I haven't tried to shift it or anything yet, do you think since the phillips screw went back in easily and tightened up I should be ok? or does the lower unit need to come off?

 

[clemsonfor]

Bringing this one back from the dead,
I recently purchased a pontoon with a 1992 25hp Evinrude.

Well, I loosened the phillips screw near the flat head drain plug on the lower unit. I loosened it just enough for a little gear lube to drip out, then re-tightened it. It tightened up as normal, no issues.

I haven't tried to shift it or anything yet, do you think since the phillips screw went back in easily and tightened up I should be ok? or does the lower unit need to come off?

Your ok. It has a shaft that goes through a hole. You have to pull it out about half way before the pin on the screw comes out of the shift cradle pivot. To check just shift it in gear and check to see if the prop engages in reverse and Foward. If it's not hooked on that pin it will not work .

 

[b.lee]

Your ok. It has a shaft that goes through a hole. You have to pull it out about half way before the pin on the screw comes out of the shift cradle pivot. To check just shift it in gear and check to see if the prop engages in reverse and Foward. If it's not hooked on that pin it will not work .

Ran the engine in a trash can full of water today and it shifted perfect, luckily. I was sweating for a bit there.

Side note, any marine grade 80w-90 is good for a 92 25hp Evinrude?

 

[clemsonfor]

Ran the engine in a trash can full of water today and it shifted perfect, luckily. I was sweating for a bit there.

Side note, any marine grade 80w-90 is good for a 92 25hp Evinrude?

Yea. The marine allows it to absorb more moisture in suspension than regular gear oil