87 omc cobra draining pivot housing

[foilled]

I removed the port screw from pivot housing and hardly any water comes out, i tried using a screw driver to removed anything but its pretty solid. Looking back into hole it seems like something solid is right at end of threads. Is it supposed to be a open hole in there or is there a super small hole back there ?

 

[Lou C]

What is inside that hole is the plastic water nipple that the hose from the transom connects to. Newer ones that I have seen have a drain hole in the side of the plastic to allow any water still in the water passages to drain. My original one did not have a hole there so I drilled one with a small drill bit. If you don’t want to do that what I did in previous years was put the drive all the way down disconnect the raw water intake hose at the thermostat housing. Hold it down to drain all the water out. Then hold it up and fill it with -100 marine AF till the AF runs out the drive water intakes. I did it that way for years and it never froze even with zero temps. I think they realized the original plastic nipple design didn’t drain well so they added the hole.

 

[Lou C]

Se the hole in the groove in the pic? I don't think the original ones OMC used had this, from what I saw on mine. I bought some as spares and noticed the difference. If you flush with antifreeze as I said above, you should not have a problem. That's what I did for years before I drilled the hole in my original one to match the newer ones being sold....

 

[foilled]

What is inside that hole is the plastic water nipple that the hose from the transom connects to. Newer ones that I have seen have a drain hole in the side of the plastic to allow any water still in the water passages to drain. My original one did not have a hole there so I drilled one with a small drill bit. If you don’t want to do that what I did in previous years was put the drive all the way down disconnect the raw water intake hose at the thermostat housing. Hold it down to drain all the water out. Then hold it up and fill it with -100 marine AF till the AF runs out the drive water intakes. I did it that way for years and it never froze even with zero temps. I think they realized the original plastic nipple design didn’t drain well so they added the hole.

Sounds good does that screw on the pivot housing have a oring on it? What about an oring between block and drain nipple? They both almost look like they couldve had one but are very worn if its not just soot.

 

[Lou C]

Yes it is supposed to have an o ring to seal it. If you need to replace the drain plug I think you can still get them from Crowley marine...

 

[Lou C]

PS every year I would remove these plugs and hardly anything came out so I always flushed with AF by filling the raw water intake hose with -100 AF till it ran out the water intakes. And I know liquid stays in there because when I remove the drive there is still AF in that water passage.
now since I drilled the hole to match how the newer style ones are made when I removed that plug yesterday to drain a LOT of water drained out...however that o ring must be in place or else it might leak water since it’s under pressure from the water pump in the upper gear housing.

 

[foilled]

Yes it is supposed to have an o ring to seal it. If you need to replace the drain plug I think you can still get them from Crowley marine...

Do you know part number for oring on pivot housing drain plug. How about the part number on the block petcock. Ive called two marinas and they say mine has no oring on the petcock for draining the block and they say my 87 cobra doesnt even have a pivot housing drain plug? Which it does. As far as i knew mines a 1987. Maybe not? Where can i get o rings i need to winterize and cant turn on or fill with antifreeze if itll leak?

 

[Lou C]

go over to Crowley marine dot com
go in the OMC catalog
stern drives
select your year & model # (in this case only the year matters because all models of the same year used the same drain plugs)
the engine drains do not have any o ring like merc uses on the plastic one. Just a brass plug that threads into a brass fitting that is screwed into the cast iron block. I use a bit of gasket sealer on them and they don't leak.
the pivot drain plug will be in the transom mount section. They are surprisingly expensive! There are 3 plugs: 2 on the starboard side one on the port. The one the water usually comes out of is the one on the port side.
I don't know why people who work in marinas are too illiterate to read a parts catalog!