Mercury 4hp gearbox.

[mercuk]

O.K I bought this secondhand gearbox. Got it home and realised it was in worse shape than what the guy had said. Pressure tested and shift shaft oil seal and drive shaft oil gone.
I replaced them for new ones.
Filled the oil back up with the blue quicksilver stuff and took it down the river for a few hours.

When I got back I check the oil again and it had changed colour to a light shade of blue.... It wasn't white or anything but was more of a "tourquoise" colour.... Is this normal?!!

I figured the only thing left was the prop oil seal and I can't get the prop off anyways....

My question is would it turn a lighter colour from use or is there still a leak somewhere...:facepalm:.. How long would it last in a freshwater environment with a "slight" leak....:redface:

Any responses would be great from all you gerbox Guru's.... I'm sure all you fellow kiekhaefer fans know all too well about gearbox leaks...

 

[mercuk]

Re: Mercury 4hp gearbox.

Right, drained all the oil from gearbox. Went in dark blue (Q/S gear lube) and came out light green, so 99% sure there's a water intrusion somewhere (all be it a minor/slight leak)

Gona pressure test again tommorow morning and hope that one of the seals i redone didn't seat properly (unlikely) or better yet, the fibre seals around the fill vent screws are doing it. Can't see it myself becasue I done them up fairly tight... But has anyone had this problem with the fibre tread washers before leaking??!!!!

Worst case scenario, prop shaft seals gone and I'm screwed.....

Wish me luck people, oh and what sort of pressure should be safe to put through it to show leaks??!!

 

[carholme]

Re: Mercury 4hp gearbox.

Fibre seals around the Fill/Drain screws are notorious and should be replaced each time. As you located the major seal leaks with your previous pressure test, I would bet the fibre seals are your problem. Hope that is all.

Gerry

 

[mercuk]

Re: Mercury 4hp gearbox.

Fibre seals around the Fill/Drain screws are notorious and should be replaced each time. As you located the major seal leaks with your previous pressure test, I would bet the fibre seals are your problem. Hope that is all.

Gerry

Hi Gerry,
Thanks for taking the time to reply to my post. I really to hope your right!!! I've had enough of working with this thing, and rebuilt everything from scratch in the powerhead and the engine itself runs like a champ.
Just annoyed I'm still getting a bit of water in the LU from somewhere....
Thanks again buddy.

 

[carholme]

Re: Mercury 4hp gearbox.

Again, hope it works out, please let us know. Where in England are you?

Gerry

 

[mercuk]

Re: Mercury 4hp gearbox.



YES!!! I found the leak!!! Just rigged up a home made pressure kit (couldn't wait till morning!) and found the strangest thing. Its not actually a seal thats gone really but where the top shift shaft oil seal is, it sits in an alloy housing and is leaking where that is!

So easy to sort out im REALLY REALLY happy I sorted this thing out because I put weeks of time into the whole engine sorted and now the last piece of the jig saw in place, its going to be a proud moment for me!!

Ive tred to show photo of me finding leaking and air bubles coming from shift shaft area:

P.S Gerry I live in Southern England, not far away from Bournemouth/ Portmouth/ Southampton area if you know it!!

 

[carholme]

Re: Mercury 4hp gearbox.

Glad you found it.

Yes, I know the area, Lived in London SE23 for several years while I worked overseas and spent a lot of time in the Hastings/Eastbourne area.

Gerry