Where's the Drain Plug ??? Merc 888, 1972

[NoName]

I pulled the lower unit off to check my impeller today. Step one is to pull the lower drain plug to drain the grease. There's a small hole near the bottom of the drive, but there's no plug in that hole. :% I separated the lower unit and got less than a quart of real milky fluid. Fluid also came out the small hole, after which water droplets came out. I pulled what looked like pieces of shale from around the pump housing and the lower shift shaft bearing was govered on goo. What the #%* is going on here?

 

[Reel Poor]

Re: Where's the Drain Plug ??? Merc 888, 1972

You have water in your drive. It will (the complete drive upper and lower) have to be disasimbeled for damage inspection and at the very least, resealed.

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

But is there supposed to be a plug in there? The hole doesn't even look threaded. I checked my neighbor's drive, it's the same one, and it doesn't look like there's a plug in that one.

 

[Reel Poor]

Re: Where's the Drain Plug ??? Merc 888, 1972

Is this the hole your talking about?

If so there is no plug, It should be open.

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

OK, call me supid, or just newbie mechanic. I turned the lower unit over and to my surprise, there's the drain plug. I couldn't see it before because all the scratches and stuff on the bottom. Now I see that the hole you have marked in your photo above is the drain hole from below the sift shaft bushing. And the reason I had gear fluid coming out there, was I split the lower unit before I had drained the stuff. With the drive tilted up, that's right where the fluid from the upper unit went before I got them completely apart. The droplets of water coming out with it at that point would be compleley normal. I'm still a bit concerned about the color of the drive fluid. What should it look like? By the way, the impeller looked fine.

 

[Reel Poor]

Re: Where's the Drain Plug ??? Merc 888, 1972

I'm still a bit concerned about the color of the drive fluid. What should it look like?

If it's milky, you have one or more seals leaking that are letting the water in the drive. The lube should be the color of your typical engine oil, sort of translucent.

Go ahead and remove the upper half, reassemble the two halfs, then have it pressure tested (pressure test is done without gear lube in the drive) to determine what seal/seals are leaking. If the water has been in there to long it can and will cause rust damage to bearings, shafts, and gears.

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

Here's a pic of the gearlube.

 

[Reel Poor]

Re: Where's the Drain Plug ??? Merc 888, 1972

:^ :'(

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

Let's try this. Go to the page below. You may have to copy & paste it, but the picture is there

www.normrogers.8m.com/gearlube.jpg

 

[Reel Poor]

Re: Where's the Drain Plug ??? Merc 888, 1972

Saw the pic in your post.

Quote: 6:18pm Today by NoName
I'm still a bit concerned about the color of the drive fluid. What should it look like?


If it's milky, you have one or more seals leaking that are letting the water in the drive. The lube should be the color of your typical engine oil, sort of translucent.

Go ahead and remove the upper half, reassemble the two halfs, then have it pressure tested (pressure test is done without gear lube in the drive) to determine what seal/seals are leaking. If the water has been in there to long it can and will cause rust damage to bearings, shafts, and gears.

 

[Scaaty]

Re: Where's the Drain Plug ??? Merc 888, 1972

Thats a real good reason, a REAL DAMN good reason, we yell at people to get a manual BEFORE making us mechanics get just a little bit richer when ya gotta take it to a shop at $80 an hour labor, which is the next thing people complain about.8)

OK, call me supid, or just newbie mechanic. I turned the lower unit over and to my surprise, there's the drain plug. I couldn't see it before because all the scratches and stuff on the bottom. Now I see that the hole you have marked in your photo above is the drain hole from below the sift shaft bushing. And the reason I had gear fluid coming out there, was I split the lower unit before I had drained the stuff. With the drive tilted up, that's right where the fluid from the upper unit went before I got them completely apart. The droplets of water coming out with it at that point would be compleley normal. I'm still a bit concerned about the color of the drive fluid. What should it look like? By the way, the impeller looked fine.

 

[Scaaty]

Re: Where's the Drain Plug ??? Merc 888, 1972

It need a good looking over...by a shop. Thats watery oil

 

[Haut Medoc]

Re: Where's the Drain Plug ??? Merc 888, 1972

Yup, water & gear lube.......
You have a problem somewhere, no doubt.....
Costly fix ahead.......JK

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

I hear what you're saying, Scaaty. Too bad the last person to have that drive open was a "certified" Merc mechanic when they replaced the impeller last September. That drive doesn't have 20 hours on it since that was done. Now the question is, do I take it back to the same place and demand they do the repair, or take it somepalce else and sink more money into it?

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

And by the way, when I pulled the lower unit, there was no O-ring on the driveshaft. I looked very carefully in the upper driveshaft splines. No O-ring. That could be where my water is coming from???

 

[Don S]

Re: Where's the Drain Plug ??? Merc 888, 1972

Was there any water in the ujoint bellows? IF there was, there is no way to keep water out of the drive.

 

[Don S]

Re: Where's the Drain Plug ??? Merc 888, 1972

And by the way, when I pulled the lower unit, there was no O-ring on the driveshaft. I looked very carefully in the upper driveshaft splines. No O-ring. That could be where my water is coming from???

Which Oring are you refering to?
"a" in the picture below would allow water into the bellows for sure.

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

There was no water in the bellows. The O-ring I'm referring to is the one on the shaft below.

 

[Don S]

Re: Where's the Drain Plug ??? Merc 888, 1972

That one is not your problem.
URL to your picture, just copy and paste this into your address bar
http://www.normrogers.8m.com/drive.jpg
Time to put the dive back together and do a pressure and vacuum check so you can locate the leak.
Reusing those pressed paper gaskets on the drain and vent plugs is also a No-No. They are a one time use item only.
Keep one thing in mind as a rule of thumb. If you take something apart that has a gasket, oring, or other type seal, replace the gasket, oring or seal. They are just too inexpensive and the consequenses to expnsive not to replace them.

 

[NoName]

Re: Where's the Drain Plug ??? Merc 888, 1972

Great advice! I'll always follow it. But tomorrow, that thing is going back to the shop.