78 merc. lower unit

[mac bass]

i have a 1978 70hp mercury. I got the boat out to get ready for the lake put the ears on and cranked it up and ran it for about 30 seconds just to check it out before heading to the lake. While I was finishing cleaning it up I noticed a dark grey or black oil and water coming out of the exhaust port in the center of the prop. I had a seal job done on the lower unit last year and it performed well all year. is this a typical seal problem? and if so what seals would cause this type of problem? I know all about finding water in the lower unit oil but i have never seen oil run out? I know that if I just go to a boat mechanic that I will need a seal job. I would like a little info on this matter before just going to a mechanic ignorant on the subject.

 

[Trent]

Re: 78 merc. lower unit

Sounds like your talking about the NORMAL unburned two stroke oil that comes out. Two strokes are nasty <br /><br />Check your lower unit to see if its full and has no water.

 

[mac bass]

Re: 78 merc. lower unit

thanks for your reply. thats what I found out today. the lower unit had some water in it but thats really not that uncomon. i had a presure tests run on the seals and even soap test the prop seal and it didn't leak off a bit. that just seemed like alot of gunk. also the boat set up for a much longer time than it ever has before so thats the first time i ever saw that much gunk. the guy that did the pressure test said the same thing those old mercs spit out a lot of snot. thanks again for your reply.