Servicing a Merc 50hp

[JSP]

I want to service the Merc 50hp (clamshell?) that I got yesterday. Any advice for do's and don'ts plus where to buy bits from would be great.
I'm thinking of respraying the cover though as it's got a few scratches on it, the leg is mint. Can you still get hold of the stickers?

[JSP]

Any ideas?

[PeterR]

Get the spark plugs from you local Motor factors and gearbox oil

[JSP]

Yeah the spark plugs are no problem it was more things like the impeller which I've never done before.
Hasn't the gear box oil got to be marine grade?

[PeterR]

I feel thats just sales b-llsh-t.Ask yourself why.Is the oil in contact with water.and if it was what will happen you will need to replace imeadiately.

[JSP]

That sounds like a sound argument Peter
Seems for the impeller I need the exact year. Any ideas how to find out the date on these mottors? Been told it looks like a 88/89?

[PeterR]

The impellar is simply to get but again questonable as when to replace.I recently had a boat with an amazing condition 1983 90 hp mercury one owner from new .It pumped water well.The owner who was a machanic swore blind the impellar had never been replaced.I did in this case have it done.Its easey if your practicle.

[JSP]

As long as I've got half an idea I love getting my hands dirty.

[JSP]

pics

[Polwart]

Originally Posted by JSP

Hasn't the gear box oil got to be marine grade?

Search here - there are differing opinions, but most people do use the marine stuff. You'll get that in any engine dealer/yacht chandlers.

As for the impellor I would definitely try to change it on an engine that is as old as that. It only costs about £15. There is a good thread here by Richard B on how to do it. Probably your worst case is you can't get the bolts out to get the leg off etc. If that is going to be a problem better to find out now.