Outdrive screw vanished....is this bad?

hshift

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After 5 years of trailering my 93 Sunbird (Ford 5.0 V8), I finally bit the bullet a bought a slip for it. Put the boat in around June, and just pulled it out to bring back to the house for the winter. I drained the block and exhaust manifolds as cold weather is forecast here in TN. When I went to drain the Cobra, I noticed the left side vent screw is missing. I know it was there when I put it in the slip, so it must have loosened and fell out while running/sitting in the water. My question, could running the drive without the screw in place have damaged anything? Thanks in advance.
 

southkogs

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I don't know the Cobras except for one thing ... the "stupid" screw: see if THIS thread helps you out at all.
 

GA_Boater

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I would guess the best thing to do get a vent screw and a set of washers and change the lube. Worst case is it's all water and best case is only a little water. But I wouldn't wait too long in case it is full of water. As far as damage to the gears, bearings, etc., you won't know 'til spring.
 

HT32BSX115

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It's possible that someone lost theirs and decided that you didn't need yours as much as they needed it!!
 

Bondo

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Ayuh,... If it's the Vent screw/ plug, there's gonna be water in the drive, insteada oil,.....

If it's the stupid screw, a slatherin' of epoxy putty will fix it right up,....
 

Lou C

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attach8949218.jpg cobra drain 2.jpg photo39564.jpg The drain/fill screws for the gear oil on a Cobra are on the RIGHT side as you face it, the only ones on the LEFT side are the DO NOT REMOVE screw and the drain for the pivot housing. There are 3 water drains for the pivot housing and they look exactly like the drain fill plugs. Looky here....There are 2 on the starboard side of the pivot housing (you have to tilt it up to see the lower one) and one on the port side.

If the screw that is missing, is the water drain one on the left side, it will not let water in the oil but you should replace it.

I always remove all 3 of these water drain screws, sometimes there is trapped water that drains but some years there is not.
 
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Lou C

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Since I removed the drive today, I investigated what passages these drains actually drain. The one on the port side, drains the water passage that goes from the drive to the pivot housing (plastic fitting that attaches to the short hose that goes from it, to the metal pipe that goes through the transom mount. Normally this drains if you have the drive all the way down, but it is possible to trap water there depending on the position of the drive.

The ones on the starboard side, drain the area around the bearing carrier and also the pocket where the bellcrank sits. If you have the drive off and shift the control into reverse and remove that lower drain screw, you can see light coming into the recess for the bellcrank. So those two on the starboard side should really be well sealed to keep water out of both areas. Usually if the drive to pivot housing gasket does not leak you will not get water in those areas but you can still get water in the pocket by the bellcrank if the seal for the cable leaks where it comes into the back of the pivot housing.
 

hshift

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The drain/fill screws for the gear oil on a Cobra are on the RIGHT side as you face it, the only ones on the LEFT side are the DO NOT REMOVE screw and the drain for the pivot housing. There are 3 water drains for the pivot housing and they look exactly like the drain fill plugs. Looky here....There are 2 on the starboard side of the pivot housing (you have to tilt it up to see the lower one) and one on the port side.

If the screw that is missing, is the water drain one on the left side, it will not let water in the oil but you should replace it.

I always remove all 3 of these water drain screws, sometimes there is trapped water that drains but some years there is not.


Thanks for all the replies. It is NOT the "never remove" screw, I've seen enough posts on this forum about that to know. It is the pivot housing vent screw on the left side. I'll be changing the gear oil in the next few days anyway for winterizing and pulling the drive for alignment check. Think it should be OK if there is normally water in there anyway and the plug was removed/fell out. Will order some extras.
 

hshift

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Jun 16, 2009
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To update, I pulled the outdrive this past weekend and the oil was fine, no water in the oil or bellows, feeling good about that, but these vent screws ain't cheap. Figured they'd be about 5 bucks tops, when in actuality the cheapest I could find one online was $21.....all that for a damn screw! At least I escaped any water in the oil issues.
 
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