Lower unit drain and fill screw gasket question

Dirkmaximus

Cadet
Joined
Sep 9, 2015
Messages
12
Hi again,

I posted about lower unit oil for my 1993 Johnson 30hp and I wasn't sure if I should add a second question to another thread or start a new topic so here it is. I was wondering when I took my drain and vent screws out, there seemed to be no washers on them, although the vent screw on the top had a taper and a gasket built on to the bolt it seemed. It wouldn't come off. The plastic washers I got from the marina seemed to fit perfectly and snug over both bolts and tightened down well and snug all around. Just wondering if you guys think it's sealed even though I put something on there that wasn't there and didn't remove anything. I checked there was no washer or gaskets stuck on the lower unit or the screws. Also no water in the oil I drained and no leaks while the boat was on the trailer after filling. Is this normal procedure or do I have to redo something? Thanks again, new boat and very little experience here, and of course little finances too so I'd like to learn.
 

jasper60103

Commander
Joined
Sep 18, 2008
Messages
2,055
I came across the same plugs on my '88 Johnson 30hp as shown in the pic below. They use the o-ring type seals.

I changed my plugs to the ones w/o the o-rings, and used the plastic washers, but this was probably unnecessary.
SDC12607.jpg
 

Dirkmaximus

Cadet
Joined
Sep 9, 2015
Messages
12
Yup that's them. See any problem with using those screws with the plastic washers? My bolts had no orings under them when i removed them. They seemed to seat just right
 

sutor623

Rear Admiral
Joined
May 23, 2011
Messages
4,089
I have used the o rings or the plastic washers. As long as they are new, and seat properly, you can use either. If your screws came out with no washer, chances are that they are still stuck to the gearcase. You can gently pry them out with a seal puller or screwdriver. DO NOT scuff the surface. Always change them with each fluid flush, and make sure to get the old washer/o ring out.
 

Dirkmaximus

Cadet
Joined
Sep 9, 2015
Messages
12
Jasper60103 Are the rubber tapers on the screws built into the screw or are those the old compressed orings?
 
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