Leaking lower unit '79 Evinrude 9.9

[Valley Boater]

I fired up my newly acquired '79 9.9 Evinrude for a test fire in a barrel. Fired up but didn't spray water after warming up for 7 minutes so it looks like an impeller replacement is in order. I drained the barrel yesterday and removed the outboard this morning and noticed the lower unit is covered in oil/lube (photos attached). Any suggestions on what I need to inspect/replace/repair?

Thanks in advance for any suggestions.

Don

 

[the machinist]

Re: Leaking lower unit '79 Evinrude 9.9

From your photos, it appears that the gear oil is coming from a leaking shifter rod seal. However that is not the rubber grommet you see in the photos as that grommet just keeps debris out of the cavity below. The actual rod seal is below that grommet in the lower unit.

Something is odd here because the oil should not be that high in the gearcase unless someone filled the gearcase way fuller than supposed to be which should be to the upper hole when the motor is standing upright. I would pull the upper stainless plug & see if oil runs out. If so let it drain down to that level & try again.

The oil color does not look right, more like there may have been rust in the gearcase & somone just filled it with a regular motor oil to sell it. What does the oil smell like? If it smells of rotten eggs, it is gear oil. If it just smells of oil then someone was not knowlegable, OR. It does not really have the appearance of water contaminated gear oil as that would be a thicker creamy color.

When you pull the lower unit to do the impeller replacement, you will be a lot closer to the situation.

Keep us advised.

 

[bktheking]

Re: Leaking lower unit '79 Evinrude 9.9

That looks like nothing I've ever seen. It isn't 2 stroke oil, the colour is wrong. It's gear oil but the nastiest gear lube i've seen next to the grey soup that came out of the 40 we did last year. Pull the 2 slotted drain screws out of the lower and drain and inspect , do NOT pull out the phillips screw out. Let us know what you find.

 

[Valley Boater]

Re: Leaking lower unit '79 Evinrude 9.9

I removed upper drain bolt and no lube came out. I then drained the lower unit by removing the lower drain and caught the lube in a paint bucket. Color wasn't milky but more like strong black coffee.

I pulled the lower unit (first time I've done so) and noticed a bunch of crud in the forward cavity and cleaned out some of the junk (more has to be removed as lower drain is blocked). I ended up with 3 different length lower unit screws (4 one size and 1 shorter and 1 longer!) Shouldn't the all be the same length?

I was expecting a tube from the water pump connecting the upper unit and do not see one (photo looking up unit attached). Also noticed what looks like "charring" on the middle of the drive shaft (also photo). I didn't pull the water pump cover as I want to finish cleaning the forward cavity before I expose the water pump.

Let me know if you see anything suspicious. All help is greatly appreciated.

Don

 

[bktheking]

Re: Leaking lower unit '79 Evinrude 9.9

No photos VB.

 

[The original Smokey]

Re: Leaking lower unit '79 Evinrude 9.9

YUK!
The seal on top of the water pump housing is shot. The large oring seal that seals the WP housing to the midsection is shot or (probably) missing.
That is a combination of lube, rust, and water. Get yourself a complete water pump kit, not just an impeller. Clean it all up and install the water pump kit. Make sure to use the big oring on top of the water pump housing to seal the housing to the midsection.
Make sure to use a new oring on top of the driveshaft, and lube the splines.

When the top seal of the pump is shot and the oring seal is shot or missing, when the motor runs it pumps water up through the seal and fills the driveshaft cavity. Then it drains out slowly, leaving behind the slop you see here. The rusty color is part from the driveshaft and part of iron-heavy water from your tap or lake the motor was in.

A WP kit should take care of this problem, no telling if the gearcase leaks or not. A pressure / vaccuum test would tell you if the gearcase leaks.

 

[Valley Boater]

Re: Leaking lower unit '79 Evinrude 9.9

Thanks for your evaluation. I've ordered a water pump kit and hope to get it installed.

Based on the photos, am I missing any parts to couple the water pump to the vertical tube?

Also - should all 6 lower unit bolts be the same length?

Thanks to all!

Don

 

[bktheking]

Re: Leaking lower unit '79 Evinrude 9.9

Verticle tube, do you mean the drive shaft or water supply tube?

If memory serves me correct, 2 bolts are longer out of the 6.

 

[Valley Boater]

Re: Leaking lower unit '79 Evinrude 9.9

This is my first water pump replacement so I'm a novice! My question concerning the verticle tube is the water supply tube. Does the "nipple" on the water pump just nestle into the water supply tube or am I missing some kind of coupler? You can see the water supply tube in on of the posted photos.

Thanks so much for your help.

Don

 

[AlTn]

Re: Leaking lower unit '79 Evinrude 9.9

VB.....I don't see the water tube in your photos. It's the hollow tube that connects the rubber grommet on top of the wp housing to the grommet in the mid. Lightly grease the inner wall of the wp grommet and the outer portion of the tube that will slide into..not over.. the wp grommet. This will help them join as you reassemble the lu to the mid. This is a hope and prayer deal as you'll not be able to see this happen. To test your wp prior to reassembly to the mid..place it in water up to the base of the wp and chuck the driveshaft to a drill. Water should flow from the grommet on the wp base as the drill spins in a cw direction.

 

[Rick.]

Re: Leaking lower unit '79 Evinrude 9.9

I see the water tube. Take some time and var-sol/paint thinner and give everything in sight a good cleaning before you put it back together. As my memory goes all six bolts are the same length for the leg the water pump will have four bolts, two lengths. Your also missing the "o' ring at the top of the driveshaft where it goes into the power head. An important item IMO. Best of luck. Rick.

 

[bktheking]

Re: Leaking lower unit '79 Evinrude 9.9

Rick's right , i'm thinking of the bottom powerhead bolts, 2 are longer than the other 4. The water tube just shoves in when putting it back together and yes replace that oring!