VP SX/Cobra - water drain plug question

[johnbo]

Hi,

Just finishing up my winterization on my '96 Volvo SX/OMC Cobra. There is a drain plug/vent plug about half way down on the outdrive. When I've pulled it out the last couple of years, no water came out of the hole or anywhere else.

This is a nasty little plug and never feels right coming out or going in. I replaced the plug last year (along with the O-ring), but that didn't change much.

I guess the question that I have is: Is pulling this really necessary? Last year, a month or so after winterization, I pulled the drive to lube the gimbal and u-joints and I didn't find water anywhere.

Does this vent just help the process of draining the water system that would happen anyway when I pull the hoses off the seawater pump? I do have a power steering cooler as well.

If its got to come out, no biggie, but I'm just curious what its role is?

Thanks,

johnbo

 

[Don S]

Re: VP SX/Cobra - water drain plug question

Are you sure that plug isn't in the bellhousing and not the drive?

 

[johnbo]

Re: VP SX/Cobra - water drain plug question

Hmmm, possibly.

It appears to vent the water passage that is sealed with the 'lower case D' shaped O-ring. So, it would be on the part of the outdrive that does not come off when I pull the outdrive for U-joint lubing.

I have trouble with the 'bell housing' name, because I think of bell housing as what bolts onto the back of the engine in a car.

Thanks,

johnbo

 

[Don S]

Re: VP SX/Cobra - water drain plug question

Well, Volvo calls it a pivot housing, Mercruiser calls it a Bellhousing. I'm just more used to calling it a bellhousing because there are more Mercs on here than Volvos.
That screw (#70) goes nowhere. Probably a holdover from when that was an OMC part. The hole is not even there on the newer models. Just a dent where it would have been drilled..

 

[johnbo]

Re: VP SX/Cobra - water drain plug question

Ahh, thanks. Part #70 was plug in question. In my drive (NC), it actually goes into the water cavity, but as I said, I've never seen water there (after my other draining).

I think that I will leave it alone.

I suspect that by the time that I'm done with my normal draining there isn't much water left in the system. I live in an area with a couple of 17-18% grades. I do the normal drains, probe them and pull the bottom ends of all of the hoses, and then take the boat for a ride. Had someone ride in the boat the first time and said that another cup or two of water came out in the downgrade. I also cycle the outdrive up and down whilst on the hill to make sure that nothing is trapped.

Thanks for the help.

Later,

johnbo

 

[Don S]

Re: VP SX/Cobra - water drain plug question

That hole only leads to the other side of the housing, not into the water system at all. There is a plastic fitting and a hose that comes thru the hole with the big plastic nut and D shaped oring.
It wouldn't matter if it was missing!!!!

 

[happycamper]

Re: VP SX/Cobra - water drain plug question

Well, I feel better now.
For 9 years, I've been taking that stupid screw out when winterizing, only to witness no extra water coming out of the drive.

I just tried it earlier today after the last run on the lake, and again, no additional water drained out.

 

[johnbo]

Re: VP SX/Cobra - water drain plug question

Of course, now I remember. When I had the pivot housing off the first winter, I remember staring at that trying to figure out what it was for. As I remember, the back side of the pivot housing is open to the water, so it pretty unlikely to be able to trap anything.

After reading happycamper's response, I wonder how many others out there are diligently pulling that stupid screw out? I guess that I wasn't alone.

Thanks,

johnbo

 

[Lou C]

Re: VP SX/Cobra - water drain plug question

Of course, now I remember. When I had the pivot housing off the first winter, I remember staring at that trying to figure out what it was for. As I remember, the back side of the pivot housing is open to the water, so it pretty unlikely to be able to trap anything.

After reading happycamper's response, I wonder how many others out there are diligently pulling that stupid screw out? I guess that I wasn't alone.

Thanks,

johnbo

Funny you should say that, my 88 OMC Cobra has 3 such drains, one on one side of the pivot housing and two on the other and most times there has not been water that drained, but a few times there has been, so I aways take em out and lube em up nice with OMC triple guard grease so they come out next time (salt water).

 

[Don S]

Re: VP SX/Cobra - water drain plug question

Lou C and anyone else with a PRE 94 OMC Cobra outdrive that has a water pump under the plastic cover on the drive. It's for the OMC/Volvo SX Style drives ONLY

THIS THREAD DOES NOT APPLY TO 93 and OLDER OMC COBRA DRIVES​

 

[Lou C]

Re: VP SX/Cobra - water drain plug question

Lou C and anyone else with a PRE 94 OMC Cobra outdrive that has a water pump under the plastic cover on the drive. It's for the OMC/Volvo SX Style drives ONLY

THIS THREAD DOES NOT APPLY TO 93 and OLDER OMC COBRA DRIVES​

I KNOW that the thread has to do with the 94 and up drives, so why do they still have this hole, when there seems to be no reason for it?
My only point is that on the 93 and older ones, there is a need for the drains.

 

[Don S]

Re: VP SX/Cobra - water drain plug question

My only point is that on the 93 and older ones, there is a need for the drains.

The original poster was asking about a 1996 (NC model) SX style drive.

Just finishing up my winterization on my '96 Volvo SX/OMC Cobra.

You are the one that brought up the older ones. Why would you do that??? Had nothing to do with the style drive johnbo was talking about.
As far as WHY Volvo left it. Have no idea, they didn't ask my permission or anyone here on iboats that I am aware of.

 

[Tom4Winns]

Looks like this thread is 10 years old but I'm having the same problem and could not find a newer thread.....1994 3.0L OMC Cobra (Volvo) sterndrive in Four Winns. I've always had a problem removing the drain screw/plug from the port side of the pivot housing on the drive. The manual says it must be removed to drain for winterizing. I've previously had to go to great lengths to get the plug out, took it to a shop to do it once, bought special tools, and this year I've managed to get it to the point it will likely need to be drilled out to remove. In searching for answers I have read threads of many people who also go to great lengths and trouble to get this plug out every year. However, I came across this thread in which 'Moderator Emeritus Don S' indicates this screw DOES NOT need to be removed for winterization. Is there anyone out there, with a '94 or newer OMC/Volvo Cobra, who DOES NOT remove this drain plug and has no problems come boating season after a cold northern winter?? Thanks in advance for your reply!

 

[GA_Boater]

Looks like this thread is 10 years old

Now it's closed. Start a new thread.