downloadable workshop manuals for marine outboards.Suggestions pls

Spurious · 13-10-2013, 12:33 AM

In particular I have a Mercury 40hp. 2 stroke, 4 cyl, built roughly between '89-'91 I believe.

I would like a downloadable PDF style of service & repair manual for this motor or similar. If anyone knows of a good virus free website where this info' can be obtained for free It'd be appreciated.

Mickxr8 · 13-10-2013, 11:58 PM

Try flea bay .

http://www.ebay.com.au/sch/i.html?_o...board&_sacat=0 ,

bought some discs for cars and all good

ohzone · 14-10-2013, 10:21 AM

I think these might get you going till you find the exact manual
http://www.mercurymarine.com/service...nes/outboards/

Pay option
http://www.selocmarine.com/engines/Mercury.php

Spurious · 17-10-2013, 01:22 PM

Thanks guys. I have downloaded the PDF for future use. I will have to buy a proper service manual in the future, or just fork out the dosh for a techy.
It was the gearbox that I was keen to learn about, removal & repairs etc.

My motor has been sitting for about 5 years. First document I got was an exploded view of the gearbox. Very helpful that one (from Marineparts.com)
I've already replaced the prop shaft seals (yes there's 2) but there's still a bit of oil seeping out from mid' gearbox. There's only 1 more 'o' ring oil seal in there so it's gotta be that one.
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RepSpec · 19-10-2013, 07:45 AM

just make sure it actually is oil mate.
i work as a marine mechainc, and rarely see those actually fail in that model (doesn't mean they wont tho)
what colour is the oil? best way to see if it is actually gear oil is to undo the screw at the bottom of the gearbox (flatbladed screw) and see what colour oil comes out. if its the same, then its gearoil. if its black, good chance its just unburnt fuel (if you have had it running)
if its oil, pull the gearbox off and pressure test to 15psi. if it drops, u got a leak. drop the gearbox in water to see where it is coming from. most likely it will be under the water pump and thoses seals will need replacing. In that model it is a housing kit which has the seals already in it. For memory the retail for a complete kit (including impeller, top and bottom housing etc) is about $150.
hope that helps!

Spurious · 19-10-2013, 11:29 PM

I'm 99% sure its gearbox oil. Gear oil has that very distinctive odour. When I replaced the 2 shaft seals I topped up the gearbox oil, it's full but pretty black & in need of a change. I got the boat as a project 3 months ago. Prior to this it was sitting for 5 years.

I also immersed the g'box leg in water to run it after replacing the rear seals, checked the box oil colour next day & still black. I expected milky colour but probably didn't run it in water for long enough ( about 45 mins over 2 sessions-left it immersed between sessions). As the leak is very minor it might take a while for water to creep in to the box.

I got the boat in mid' June & today was the first time I took it out.
See here: http://youtu.be/LaR7dsJ2FwY
About 4 hours on & off plane in salt water. I'll change the oil in the next week or so & then I'll know if & how bad its leaking/taking in water.

I have already renewed the impeller & it's surrounding seals/gaskets.

Thanks for the advice too.

Spurious · 20-10-2013, 07:43 PM

I take back what I said RepSpec. Having used the boat yesterday there was a bit of oil on the plastic under the g'box today. I did a scratch & sniff & it doesn't smell like box oil. Smells like 2 stroke. Thanks for the heads up. Crisis averted.

RepSpec · 21-10-2013, 08:18 AM

glad i could help mate. the amount of people we get calling because there gearbox is leaking when it is just unburnt 2stroke is heaps!

Spurious · 23-10-2013, 09:47 AM

After I changed the prop shaft seals there would have been a bit of excess box oil in the housing, this is most likely what I could smell & made me think it was still leaking. I couldn't be happier with the outcome considering I got the boat & motor for free. 3 months & about a grand to fix but now it's "happy boating'.
I put some pics up in the Bar/boating section in "show us your boat".