Cant remove bottom of pump housing from the Lower Unit.

[michaud500]

I have a 1976 50hp #2629264. I reoved the lower unit to replace the impeller and decided to try and remove the entire pump to see how things work. When I got to the lower pump housing I could not budge it. I tried a piece of wood and a mallet nect to the exhaust port and gently but firmly tapped the wood. It moved a little bit, but I tapped it back. I tried moving the front bot there is no way to get underneath it that I can figure. In the manual it said something about a screw hole but I see nothing of the such. I would like to get it off but will I need to replace the pump entirely with a repair kit after having to force the part off? The parts are old the impeller was trash and the seals are old. Any and all advice is welcome!

One more thing does someone have a parts # list with pics so I can get the correct parts?

Thanks

 

[fisherguy123]

Re: Cant remove bottom of pump housing from the Lower Unit.

One more thing does someone have a parts # list with pics so I can get the correct parts?

Thanks

maybe the attached pic may be a help......from my manual for 50 mercs

 

[aussieflash]

Re: Cant remove bottom of pump housing from the Lower Unit.

Try a couple of pry bars or large screw drivers on both ends.For part# and pics try Crowley Marine.

 

[carholme]

Re: Cant remove bottom of pump housing from the Lower Unit.

That s/n actually comes up as:

50 500 4-cyl 2514919 2736806 1969 USA

From here:

http://www.marinshopen.se/Motorer/O...Mercury2takt4cyl4085hp/tabid/487/Default.aspx

It is a model 1500109.

Parts Listing:

http://www.crowleymarine.com/mercury-outboard/437.cfm

Can you confirm the s/n as you had indicated that it was a 1976.

Gerry

 

[Faztbullet]

Re: Cant remove bottom of pump housing from the Lower Unit.

Remove the flush plug screw and it will pop on out....

 

[michaud500]

Re: Cant remove bottom of pump housing from the Lower Unit.

Sorry guys it is a 1969 not a 1976. And yes I did remove the flush plug. It was packed with sand that I hans to clean and flush out. That is the main reason I am trying to get everything apart. I want to make sure that there is nothing in the gear case. Do you think that there might be trace elements of sand (I cleaned it really good Idid it in the bath tub my wife was happy with me) that are preventing me from removing the base? I went to Crowly(thanks) and it seems that 1969-1976 are the same parts for the most part.

 

[carholme]

Re: Cant remove bottom of pump housing from the Lower Unit.

In this link you will see item 12, an O ring which surrounds the lower part of the pump base. You can see the channel for it on item 13. This is all that is holding the pump base in there. You have already had it moving and it should pull straight up. You will have to pry from both sides or the front and back to get it to move up far enough to break the hold of the O ring.

http://www.crowleymarine.com/mercury-outboard/parts/437_19.cfm

Gerry

 

[michaud500]

Re: Cant remove bottom of pump housing from the Lower Unit.

Got it! Thanks for the help! Will give it a shot today.

 

[michaud500]

Re: Cant remove bottom of pump housing from the Lower Unit.

So I got the housing out. I bent a nail to put a little hook on the end and attached it to a small vice grips. So I have discovered a bit of sand around where the housing was. Shall I tip on it s side and spray cleaner to flush or remove the Drive Shaft? To get out the Drive Shaft do I first have to remove the Prop Shaft?

Thanks

 

[carholme]

Re: Cant remove bottom of pump housing from the Lower Unit.

If you tip it on it's side the LU oil is going to greet you. Same if you try to spray anything in there as the seal is removed when you pulled the pump base.

To remove the d/s assy, you have to pull the prop shaft assy, undo the pinion gear retaining nut and remove the d/s.

I can't remember if you said you had a manual but here is a link to the condensed version of the Clymer manual. Let the page load for several seconds and then download soonest to your computer as the link is short lived.

http://web.ebscohost.com/serrc/pdf?...c-af12-b5003958df91@sessionmgr12&vid=4&hid=18

You will find the procedure for the LU beginning on page 284. Make sure you note the position of all shims.

Gerry

 

[Moody Blue]

Re: Cant remove bottom of pump housing from the Lower Unit.

Shall I tip on it s side and spray cleaner to flush or remove the Drive Shaft? To get out the Drive Shaft do I first have to remove the Prop Shaft? Thanks

Unless you are experiencing problems with the lower unit, I would recommend that you leave it alone. It is a lot of work and involves some specialized tools to remove the driveshaft.

Clean up the crud carefully (try not to get stuff down into the upper driveshaft bearing), put it back together and go boating. If you really need to, I guess you could drain the lower unit oil and then flush the gear box with solvents then refill with gear oil.

 

[carholme]

Re: Cant remove bottom of pump housing from the Lower Unit.

I don't know what special tools you are talking about, He is not going to overhaul it. Other than a tool to remove the cover nut, which he can make, it's tapping the case off the carrier assy, undoing the pinion nut and tapping the remainder of the housing off the d/s assy.

Gerry

 

[aussieflash]

Re: Cant remove bottom of pump housing from the Lower Unit.

Id love to see a pic as i pulled my lower housing(TIGHT)and it left lower seals around shaft.I would not be pulling shaft just for a bit of sand.Clean and go fishing.

 

[michaud500]

Re: Cant remove bottom of pump housing from the Lower Unit.

I turned the unit on its side and drained the gear oil out. I also sprayed wd40 where there was sand and had it drain into a oil pan. There was a lot of sand there, about a tablespoons worth. sprayed wd40 through the bottom drain hole while holding the unit upside down. I also turned the shaft while it drained. I dont hear anymore grinding/crunching like before, I am gonna leave to drain overnite and fill it in the morning and rotate shaft to look, feel for contaminant.

What kind a pic do you want? I should have taken one when I pulled the LU, to show how packed with sand it was. The lower seal stayed on mine but it was also broken, time to replace. One more question, there is some sort of hole in the lower pump housing. Most likely from manufacturing, it is on the right side, from the drive shaft area through to the outside of the pump housing. Not where there
is a source for water but oil. would that be for exspansion when the oils gets hot.

Thanks for the help!!!!

 

[Moody Blue]

Re: Cant remove bottom of pump housing from the Lower Unit.

I don't know what special tools you are talking about, He is not going to overhaul it. Other than a tool to remove the cover nut, which he can make, it's tapping the case off the carrier assy, undoing the pinion nut and tapping the remainder of the housing off the d/s assy.
Gerry

Why take the chance of breaking something trying to get a perfectly good 43 year old lower unit apart for no good reason, is my point. I liken it to removing a car engine to change the oil. Sure it can be done, but not the best approach.

 

[Moody Blue]

Re: Cant remove bottom of pump housing from the Lower Unit.

One more question, there is some sort of hole in the lower pump housing. Most likely from manufacturing, it is on the right side, from the drive shaft area through to the outside of the pump housing. Not where there
is a source for water but oil. would that be for exspansion when the oils gets hot.
Thanks for the help!!!!

That hole is weep hole of some sort. Probably allows water, that might get past the impeller and into area above the seals, to drain out into the LU cavity. This hole is located above the seals and will not be exposed to oil in the LU.