mark 78 lower gear case seals

[gwmark78]

I have my water pump housing off and now I'm looking at the cast pressed in insert that holds the stainless impeller cup. What is the best method to remove that insert so I can get at my lower seal? I know there is a special tool, but can it be done without it and not destroying that piece. Any help would surely be appreciated-Thanks Gary

 

[Yepblaze]

Re: mark 78 lower gear case seals

Pull the propeller shaft, gear, and carrier.<br /><br />Place driveshaft in vise horizontally.<br /><br />Remove pinion gear nut, or bolt.<br /><br />With a block of wood and a very large hammer, (and an assistant to steady the lower unit housing) beat the lower unit housing away from the vice.<br /><br />The shaft is stepped and the bearing below the water pump cartridge will become the puller.<br /><br />Of course lots of heat from propane torch, along with flaming/smoking aplications of penetrating oils add to the excitement and theatrical effect.<br /><br /><br />

 

[gwmark78]

Re: mark 78 lower gear case seals

Thanks Yepblaze for the response, I'm going to give it a try but I guess I need to make a tool to remove the prop shaft retainer piece (the threaded cast piece with the 4 holes). I'll let you know how it goes--I love the smell of flaming liquid wrench!

 

[Yepblaze]

Re: mark 78 lower gear case seals

Sometimes it can be the same kind of thing there, with the heat and penetrant.

 

[gwmark78]

Re: mark 78 lower gear case seals

Well I'm still trying- I have soaked in penatrating oil for days and have beat the ---out of it and cannot get it to budge. Any other thoughts other than get a bigger small sledge hammer?

 

[run13.1miles]

Re: mark 78 lower gear case seals

There is a threaded retainer above the drive shaft bearing.You can "hit" all you want to and it will not do any good!The water pump insert must be removed first. Some times it has to be destroyed by drilling on the sides. Some times two screwdrivers can be used to try to gently pry the cartridge up.A special tool is needed to correctly remove the cartridge.I know how frustrating this can be. I have been there! Good luck,Bill

 

[gwmark78]

Re: mark 78 lower gear case seals

run 13.1miles-I wish I would have read your input-Yeah you can beat all you want- I found this out sunday after many hours of frustration. I thought I remembered something in my book about that but my book was 200 miles away at the lake. I ----near ruined the threads on the retainer! It was a real bugger to get out after I welded up a spanner tool to remove it. Also It was a reverse thread which at least I fgured out after rapping on the tool and nothing happening. I did destroy the water pump cartridge because after many hours of prying I could see it was not coming out. But I was able to locate this scare part today. Thanks for your input Bill-<br />Gary