Logo

Lower Unit Blues

jwales2112

New member
I put a new water pump and replaced the 2 shaft seals under the new water pump, replaced the 2 prop hub seals also. Motor pees like mad now which is great. I checked the lower unit and tons of water in there. Drained it, refilled, replaced the o-rings on the lower unit screws, ran it last night in lake and still tons of water in the lower unit. When I was fishing the outer prop shaft seal out I gouged the inside of the inner hub a tad. Not the shaft, just the inner hub. Could this have screwed me?
 
Some sealer would likely take care of a wee gouge.----Did you replace shift rod o-ring ?----Model # of the motor ?
 
I actually did smear a bit of sealant over the wee gouge prior to pressing the seals in the hub. When you say shift rod o-ring do you mean there is an o-ring where the lower metal shift rod enters lower unit in image? If so I did not monkey with that. Is that removeable?shift.jpg
 
I actually did smear a bit of sealant over the wee gouge prior to pressing the seals in the hub. When you say shift rod o-ring do you mean there is an o-ring where the lower metal shift rod enters lower unit in image? If so I did not monkey with that. Is that removeable?View attachment 23600
Yes.Look at the parts diagram.O ring down inside the brass bushing where rod goes thru.
 
Hells Bells. I see it in diagram. Let me guess, a special tool is required to get that out? Is there a MacGyver method perhaps?
Method I heard of ,,remove shift shaft and tap brass bushing with 1/4 x20 thread and use a piece of threaded rod and a steel plate and nut to act as puller.
 
Method I heard of ,,remove shift shaft and tap brass bushing with 1/4 x20 thread and use a piece of threaded rod and a steel plate and nut to act as puller.

Thanks that sounds like a good idea. So the shift rod just turns out like a bolt then? It must be threaded on the end I can't see?
 
I put a new water pump and replaced the 2 shaft seals under the new water pump, replaced the 2 prop hub seals also. Motor pees like mad now which is great. I checked the lower unit and tons of water in there. Drained it, refilled, replaced the o-rings on the lower unit screws, ran it last night in lake and still tons of water in the lower unit. When I was fishing the outer prop shaft seal out I gouged the inside of the inner hub a tad. Not the shaft, just the inner hub. Could this have screwed me?

That sounds an awful lot of water getting in via the shift rod seal unless it it is completely knackered

Did you put the other seals in correctly.?

You don't tell us what engine , but they usually go in back to back, i.e. with the lips facing away from each other

Did you replace other gaskets or O rings which you disturbed? Did you fit new seals on the drain and level screws?
 
That sounds an awful lot of water getting in via the shift rod seal unless it it is completely knackered

Did you put the other seals in correctly.?

You don't tell us what engine , but they usually go in back to back, i.e. with the lips facing away from each other

Did you replace other gaskets or O rings which you disturbed? Did you fit new seals on the drain and level screws?

Thanks for the response. The engine Model is J25telcca. I did take pics of every step before tearing it apart for reference and yes I made sure seals were back to back with lips away. I replaced every oring and gasket I encountered while rebuilding water pump and sealed metal plate gasket with sealer as well. As I mentioned earlier, the water pumps works awesome now. First trip I came back and check lower unit and tons of water was in there. Replaced orings on lower unit fill/check screws, refilled with lower unit oil, hit the lake and again, lots of water in lower unit when I got back in and checked.

I pulled lower unit today and pics are below. The first time I pulled it when changing water pump the copper tube stayed in the upper, this time it came down with the lower. Not sire if that matters. Grey sludge everywhere with ooze marks possibly indicating it's running down the copper pipe? Any ideas? TNX



1.jpg2.jpg3.jpg
 
UPDATE

I bought a used lower unit with new water pump installed in it. The lower was pressure tested to 12 PSI. I bolted it on and pumped it full of fresh oil. Hit the lake and motor ran awesome. Tons of water coming out of exhaust/pee hole. Get back in and check lower and lots of water mixed with oil. So I now have 2 lower units, both with new water pumps that work great, yet when I put either on motor and run it and check lower the the oil comes out with water in it. So, if you have a lower unit that is sealed well, what could cause it to become infused with water so quickly? Back blast from the exhaust or something? I'm confused....
 
Yes that lower shift rod screws right out.-----A 5/16-NC tap works a lot better in the bushing.

Thanks, Do I have to unscrew the phillips screw next to the bottom drain plug before I attempt to unscrew the lower shift rod and pull it up through the bushing and o-ring?
 
Do not unscrew the Phillips. I don't mean to butt in,I just have one guestion,are you concerned about water in you lower gear oil or the emulsion in your midsection?
 
Do not unscrew the Phillips. I don't mean to butt in,I just have one guestion,are you concerned about water in you lower gear oil or the emulsion in your midsection?

Thanks! There's water in lower unit after replacing water pump and ever seal except the shift seal. That's my main concern. Is the emulsion in lower something else I should be concerned about?
 
Back
Top