Outboard engines and morse controls

[Verboaten]

Hello all,

 

I have finally had the opportunity to look at my Mercury 40hp outboard and I'm really unhappy with the condition of it, for an outboard that was supposedly serviced this time last year the condition is poor in the sense that the wiring is shot in various places, one of the prop fins has a chunk out of it and it appears the engine had an electric start but the wiring has perished and parts for this have been removed.
Also the positive wire appears to be connected by the last 3 strands of it's inner copper wire, so far I have tilted the engine out of the water and removed the spark plugs which are BUHW-2, a design of spark plug I have never seen before. (http://www.ebay.co.uk/itm/NGK-BUHW-2-5626-Spark-Plug-Mercury-Mariner-2-Stroke-Outboard-Engines-4hp-90hp-/181528880213?hash=item2a43f6e455:g:BOsAAOxyJX1TF5M2)

I have no idea what model of outboard it is, or it's age, only that it is a heavy unit, I thought it was a four stroke but could not find any oil filler caps so possibly a 2 stroke premix?

Knowing nothing of the engine, I am now thinking the best idea would be to have a boat mechanic refurb the engine (rewire, change the prop and service), can this be done with the engine in situ or would I need to remove the unit and take it to a specialist?


The good news is that the outboard is currently connected to a throttle/gear control box and steering wheel via a morse cable system, I'm now thinking of replacing the entire outboard and selling off the mercury unit after it's refurb, but are the controls universal and would it be a simple case of disconnecting the throttle arm and attaching the cables for throttle/gears?

Thank you!

Edited October 18, 2015 by Verboaten

[Alan de Enfield]

 

The good news is that the outboard is currently connected to a throttle/gear control box and steering wheel via a morse cable system, I'm now thinking of replacing the entire outboard and selling off the mercury unit after it's refurb, but are the controls universal and would it be a simple case of disconnecting the throttle arm and attaching the cables for throttle/gears?

 

Thank you!

 

 

 

99.99% sure it will be a 2-stroke premix engine at 50:1

A new prop will probably cost £150 (depending on type)

Sell it as is - 2nd hand outboards have a low value and you will spend more 'refurbishing' it than you will probably get back selling it.

Does it have a red-band, or a blue-band around the engine cowl/lid ?

 

The cables should be interchangeable with any outboard (but - you may need to adjust the length or outer casing gripping point)

Edited October 18, 2015 by Alan de Enfield

[Verboaten]

 

99.99% sure it will be a 2-stroke premix engine at 50:1

A new prop will probably cost £150 (depending on type)

Sell it as is - 2nd hand outboards have a low value and you will spend more 'refurbishing' it than you will probably get back selling it.

Does it have a red-band, or a blue-band around the engine cowl/lid ?

 

The cables should be interchangeable with any outboard (but - you may need to adjust the length or outer casing gripping point)

 

Thank you so much, I presumed being a big outboard it would be a 4 stroke but I guess twin cylinder 2 stroke is possible.

The outboard casing has a blue band around it, I presume that means something?

 

I'm looking at a few other local outboards on Ebay, one of which is a SELVA 2 stroke 20hp which I imagine should be adequate for both river/sea ventures.

[Alan de Enfield]

The outboard casing has a blue band around it, I presume that means something?

 

 

 

Don't remember the exact years but pretty sure that makes it 1980's

[Phil Ambrose]

I think you have to weigh up the possible costs against the cost of a replacement. The wiring would not ne expensive to replace yourself, yes you would need to replace the prop but may be able to get a decent 2nd hand one for not too much. The only sticking point as I see it is the electric start. Having had similar issues with an old outboard I found replacement starter motor impossible to source, however a mate who is into motor bikes and who runs a MOT test station help out. The starter has much in common with a bike's and he called in a favour and got it rebuilt, new bearings , brushes and commutater skimmed and coil rewound all for £20-00. So pause for thought before shelling out.

Phil

[ditchcrawler]

So if you didn't know if this outboard was 2 or 4 stroke I take it you have never run it, so you have no idea what its like mechanically and the supposed overhaul was carried out for someone else.

[Tony Brooks]

The spark plug is a surface discharge plug and normally has a very long life because the spark can spark from anywhere around the electrode to anywhere on the case. Unless the centre electrode is worn to almost a point I would just wipe them clean and refit.

 

That type of plug is used with electronic ignition (capacitor discharge) and earlier versions used contacts under the flywheel much conventional outboards. Later one were fully electronic with no contacts and I have never found how the electronic units can be tested using ordinary tools. Maybe a workshop manual has more info. If the electronic unit has failed then it could be prohibitively expensive to fix. Best see if you can get the engine spinning and look for sparks before spending too much on it. I fear the "overhauled last year" was just an Arthur Daley's way of passing off a dodgy engine.

 

I agree the engine is likely to be from the late 70s/80s and is likely to be a 2 stroke.

 

We operated de-rated 9.9 hp versions on our day boat fleet and the Mercurys knocked the spots off the OMC engines for reliability so with CD ignition, even though its a two stroke, it would be worth keeping IF you can get it running. The plugs are unlikely to oil up.

 

I seem to recall our earlier OBs had red bands and the later ones blue.

 

Talk to Steel Development at Merton about the cost of getting the prop repaired. They re-bush OB pros as well as repair them and if their repairs stand day boat use they should be fine for owners.

[craftycarper]

The spark plug is a surface discharge plug and normally has a very long life because the spark can spark from anywhere around the electrode to anywhere on the case. Unless the centre electrode is worn to almost a point I would just wipe them clean and refit.

 

That type of plug is used with electronic ignition (capacitor discharge) and earlier versions used contacts under the flywheel much conventional outboards. Later one were fully electronic with no contacts and I have never found how the electronic units can be tested using ordinary tools. Maybe a workshop manual has more info. If the electronic unit has failed then it could be prohibitively expensive to fix. Best see if you can get the engine spinning and look for sparks before spending too much on it. I fear the "overhauled last year" was just an Arthur Daley's way of passing off a dodgy engine.

 

I agree the engine is likely to be from the late 70s/80s and is likely to be a 2 stroke.

 

We operated de-rated 9.9 hp versions on our day boat fleet and the Mercurys knocked the spots off the OMC engines for reliability so with CD ignition, even though its a two stroke, it would be worth keeping IF you can get it running. The plugs are unlikely to oil up.

 

I seem to recall our earlier OBs had red bands and the later ones blue.

 

Talk to Steel Development at Merton about the cost of getting the prop repaired. They re-bush OB pros as well as repair them and if their repairs stand day boat use they should be fine for owners.

. I picked up two of these old blue band Mercury,s on the back of my scrap truck this year one was a large 80hp and the other a little 7 horse twin, sold the big one for £150 without even taking it off the truck, and after a bit of a carb clean the seven starts and runs a treat, sounds very much like an old Vespa, nice little motor especially for free, but there is also still a bit of a fan base for the bigger ones, I saw one sell on eBay for £500 as spares recently,

[Verboaten]

Hi guys,

 

Thank you for all the replies, I've now had the chance to get back down to the boat and get some more pictures.

From my investigations It appears the engine is a 1978 Mercury 402 40hp 2 cylinder, 2 stroke Short Shaft outboard.
I've linked to pictures of the condition below, my aim now is to remove the engine and sell it privately as spares/repair and replace it with a (hopefully) 4 stroke 15hp+ unit.

 

 

 

 

 

 

[Alan de Enfield]

Before removal - just check that with the engine lowered into postion that the cavitation plates are level (or fractionally below) the bottom (keel) of the boat. This is the correct 'leg length'.

 

Your prop wants to be in 'clear water' (not obscured by any part of the boat but also not too deep below the boat.

 

I say to check it as it may actually be the wrong length and if you go and buy another 'short shaft' you may be compounding the issue.