L/U leaking gear lube

[andy6374]

Haven't posted in a while, but it's nice to see alot of the same names. Of course I have problem and that's why I'm looking to iboats once again.

Engine: 88' V6 200hp black max, 1.87 gear case.

I found the L/U seeping gear lube from one of the "weep" holes on the L/U above the waterpump intakes on the starboard side. I know it was gearlube because there is no mistaking that smell.

At any rate I pulled the vent and drain/fill screws and about a 1/4-1/2 of clear water came out. Yikes!. But the magnetic screw only had the normal shavings so I figured I was fine. ALSO, both the vent and fill screws backed up way too easily, I mean I could have backed them out with a nickel. So naturally I figured that that is where the water was coming in. So I filled and drained a couple times and put new screws and o-rings back in and tighten the screws as hard as I could.

But, what I don't get is why would gearlube be coming out that weep hole. It must mean a seal has blown too, right? Must be the driveshaft or shiftshaft seals right?

The L/U shifts fine and makes no noises. I've used the boat 3 times since, I'm eager to see if there is water in there again.

What do you think.

-andy

 

[MadProps]

Re: L/U leaking gear lube

I agree , driveshaft & or shift shaft leakage

 

[finlay]

Re: L/U leaking gear lube

you need to pressurize your gear box to about 7 psi then spray sopy water on the prop shaft and drive shaft and shift shaft seals. you will have to take your water pump base of the get to your drive shaft seal.....

 

[Chris1956]

Re: L/U leaking gear lube

Andy, I recommend you change the driveshaft seal located in the water pump base. Also put on a new oring on the waterpump base as well as a gasket. Inspect the driveshaft where it meets the seal and make sure it is clean and smooth. The shift shafts leak a whole lot less than the driveshaft seals.

 

[andy6374]

Re: L/U leaking gear lube

Chris-

What's involved in replacing those seals? Do you need any "Merc" tools? I've always done all the maintenance on this engine and I have the factory manual, just wondering about any potential pitfalls I should be aware off before getting into this project.

How easily should/does the water pump base lift off?

If I don't have the merc tools, how can install the seal?


Thanks-
andy

 

[Chris1956]

Re: L/U leaking gear lube

No special tools are necessary. It makes sense to buy a new waterpump base since it will have the new seal already installed. Buying just the seal restricts your parts selection to the dealer, costs about the same as buying the whole housing and you can easily damage it installing it. Get a impeller repair kit as well. The top housing is likely Ok to reuse. See if the ss liner is scored. if so, replace the upper waterpump housing as well.

Put the motor in neutral, remove the six bolts holding the gearcase to the midsection, and remove the gearcase. The sixth bolt is under the zinc anode, above and behind the prop. You will need to remove the zinc with a 1/2" socket, allen wrench or 12 point socket, depending on what it has.

Now remove the 3 or 4 bolts holding the waterpump cover, and remove the cover, impeller, base plate and driveshaft key. Now gently pry up on the waterpump base with some flat irons or large screwdrivers. When it is out, clean up the area, install the gasket on the new base, install the new oring on the new base, oil it up, and oil the driveshaft and driveshaft seal and slide it into place. Install gaskets on the new base plate (both sides), and install it. Install the impeller by sliding it down the driveshaft and over the key. Now lubricate the upper pump liner and place the upper waterpump over the driveshaft. Push down on the upper pump while turning the driveshaft CW. The impeller will bend until the cover can go over it. Install the nuts and washers and the self tapping screw. Install the slinger (heavy rubber washer) on the driveshaft. It sits on top of the waterpump. Grease the splines of the driveshaft and shift shaft, and install the white plastic water tube extension into the pump.

OK install the gearcase. Shove it up until it stops, then turn the flywheel until the spline meshes. Now move the upper shift rod until it mates with the lower shift rod. I can get to mine from the outside, and a needlenose plier can move it. Now you should be able to get the front nut onto the gearcase stud. Now work the gearcase up using just your hands(no tools), tightening the nuts by hand as you go. If it wont go in with your hands, something is wrong.

Drain and refill the gearcase. Gaskets for the drain and fill plugs come in the impeller repair kit.

BTW - The 3/4" oring will fit the PTT piston rods, if your seal starts to leak

 

[andy6374]

Re: L/U leaking gear lube

Great. I replaced the waterpump several times so that part isn't a problem. BTW, when replacing the waterpump I usually just buy a whole waterpump kit and replace everything (it's worth it to me).

Glad to hear replacing the base is easy. Thanks. I'll fill everyone in after I replace the waterpump base.

 

[andy6374]

Re: L/U leaking gear lube

BTW - The 3/4" oring will fit the PTT piston rods, if your seal starts to leak

No sure what you mean here, PTT piston rods?

 

[Chris1956]

Re: L/U leaking gear lube

Andy, If you have power Trim on that motor, and it is the two cylinder version, the orings that come in the waterpump kit are the same as the ones installed in the PTT cylinders to seal the 3/4" rods.

 

[andy6374]

Re: L/U leaking gear lube

Roger that.