Water in lower unit

[goblerblaster]

I have a 2001 Merc 90 hp 2-stroke that I got on a used party barge. It was supposed to have a new impellor and it does pee a strong stream of water while running. However, I keep getting water in the lower unit when I put it in the water, but not if I run it on Muffs. I got a new seal kit and in preparing to put that in, I noticed that the speedometer tube was not connected to the little stub pipe. In essence there was no rubber tube going from the lower unit to the speedo. Could this be letting water into the lower unit ??? I thought I would ask the experts before putting on a seal kit !! There is no lower unit grease or water leaking from the prop seal even after the boat sits on the trailer for 3 weeks. When I pull the lower unit oil filler plug, straight water shoots out as if it is under pressure for the first few seconds, and then a mix of clean lower unit oil and water will begin to drip out like normally happens when you change the lower unit gear oil.

I had asked about this before I noticed the speedo tube not connected and the general opinion was that the shift shaft or drive shaft seal was letting water in. Just thought I would check again since speedo tube was not connected.

Any suggestions or thoughts appreciated.

 

[racerone]

Re: Water in lower unit

Speedometer tube does not put water into the gear oil.------Have a shop pressure test the gearcase.-That is how leaks are found.

 

[carholme]

Re: Water in lower unit

Two of the most common leaks are at the Fill/Drain and Vent screw areas of the LU when new seals are not replaced. See items 5 in this link:

Mercury, Mercruiser, Force, etc. - Gear Housing, Drive 2.31:1 USA 0T627235/BEL 0P215669 and Up - 75/90 H.P. 65 JET (3 CYLINDER)

When you dropped the LU did you notice any oil on top indicating a shift shaft seal or water pump base seal leak?

What is your engine s/n and do you have the service manual, 90-830234? If not, see my message to you in Notifications at the top of this page.

Gerry

 

[Mi duckdown]

Re: Water in lower unit

When you remove the fill/ drain and vent screws, check to make sure that parts of the old gaskets are not stuck to the lower end. and yes use New gasket everytime