Milk Coming out of lower unit

[bannerd]

Hey all, I change my lower end unit gear oil every year and I went to change it this year. It was a white thick milk substance. I take it water is getting inside the lower unit.. the question is how/where? I thought these were sealed? the bolts have new rubber washers.

 

[fireman57]

Re: Milk Coming out of lower unit

Usually the culprit is the nylon washers on the fill/check bolts. If you check it every year you want to change these out because they don't want to seal once they have been used and broken loose once.

 

[bannerd]

Re: Milk Coming out of lower unit

Usually the culprit is the nylon washers on the fill/check bolts. If you check it every year you want to change these out because they don't want to seal once they have been used and broken loose once.

is there a part #?

 

[emoney]

Re: Milk Coming out of lower unit

Not sure of the part #, but they're pretty standard washers and just about any Marine Dealer will have them in stock. I always order them by the dozen, as my lower unit has 3 plugs and if you don't have a spare, Mr. Murphy ('s Law) will all but guarantee that you lose one. It wouldn't hurt to have your LU pressure tested too, especially if it's getting any age on it.

 

[kfa4303]

Re: Milk Coming out of lower unit

HI bannered. There are several places water could be getting into the gearcase, especailly on the old vintage motors. The easiset/most obvious place to check are the white, nylon crush washers mentioned in the previous post. You can get them at any OMC dealer, for a few buck, or right here at iboats. Of course, the only way to be completely sure is to reseal the LU, which invloves changing a few oil seals, o-rings and washers. It's a medium difficulty that you can do yourself with basic tools and $25 seal kit and some 3M 847 gasket sealant. Here's a link on how to do a basic reseal job on a vintage OMC motor. Btw, what year/model is the motor?

http://forums.iboats.com/showthread.php?t=277190&highlight=lower+unit+seal+kit+installation

http://www.youtube.com/watch?v=neYroHtSheQ

 

[bannerd]

Re: Milk Coming out of lower unit

HI bannered. There are several places water could be getting into the gearcase, especailly on the old vintage motors. The easiset/most obvious place to check are the white, nylon crush washers mentioned in the previous post. You can get them at any OMC dealer, for a few buck, or right here at iboats. Of course, the only way to be completely sure is to reseal the LU, which invloves changing a few oil seals, o-rings and washers. It's a medium difficulty that you can do yourself with basic tools and $25 seal kit and some 3M 847 gasket sealant. Here's a link on how to do a basic reseal job on a vintage OMC motor. Btw, what year/model is the motor?

http://forums.iboats.com/showthread.php?t=277190&highlight=lower+unit+seal+kit+installation

http://www.youtube.com/watch?v=neYroHtSheQ

Thanks, the motor is a 1979 evinrude 9.9hp

 

[boobie]

Re: Milk Coming out of lower unit

As said above, have the lower unit pressure and vacuumed checked to take the guess work out of where it's leaking. Then go for the repair.

 

[Bamaman1]

Re: Milk Coming out of lower unit

Boobie's right about having the unit pressure and vacuum tested. You're going to have to have a new seal kit put in it. There area seals behind the prop and where the drive shaft goes up to the motor--by the water pump. The question is whether damage has been done to your gear case? The seal testing needs to be done about every 5 years whether there's a problem or not. They're about a $350 repair job on a larger motor.

My Yamaha 115 hp gear case was damaged by the water when seals went out, and it's cheaper and easier to replace the lower unit with an aftermarket new unit with a 3 year warranty--$845. You don't want to ask how much a factory OEM lower unit is. I replaced it--with a new Yamaha 150 hp on a Bennington tritoon.

 

[kfa4303]

Re: Milk Coming out of lower unit

Here's another handy link.

http://www.leeroysramblings.com/Johnson 9.9_15.htm

 

[Joshua2]

Re: Milk Coming out of lower unit

I just had the same thing on my 76 15 evinrude... I replaced the seals behind the prop and right below the water pump but I didn't replace the washers at the fill and check holes but now I am never thought about those! But like the guy said it's better to replace seals than gears or gear cases! But I could do it I'm sure u can I pulled the prop and gears and just knocked them out from the back and the ones under water pump came fairly easy I just had to wing it and use welding rod with a hook and clamped vise grips on it and knocked on the vise grips and they came out pretty easy...but there's a little tool you can get to pry them out of there even with a shaft running through them good luck! Oh Use a socket or pipe to carefully knock em back in there or a c clamp to push em in.

 

[bannerd]

Re: Milk Coming out of lower unit

I'll have to get a seal kit. It might be the seals in the prop that is allowing water in. Anyone recommend a brand of lower unit gear oil? I've been running supertech stuff from walmart (synthetic).

 

[kfa4303]

Re: Milk Coming out of lower unit

The brand of oil doesn't matter much as long as it 80-90w marine gearcase oil. I just use the Wal-mart brand myself. Here's a link on how to change the oil seals for a vintage OMC motor. You can get a seal kit right here at iboats or about $25. You'll also need a tube of 3M 847 gasket sealant, which you can usually get a Grainger's, or online.

http://forums.iboats.com/showthread.php?t=277190&highlight=lower+unit+seal+kit+installation