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buying help needed! Mercury 402 40hp

O

oldspeedy

New member
Hey guys im new here and to most boat motors. i have a little 13 foot speedboat im looking to put a 40hp motor on it. i have located what seems to be a deal. it is a late 70's or early 80's mercury 402 40hp. electric start with recoil start also. it comes with control box,wiring harness, choke button, shift and throttle cables. it is a single carb 2 cylinder. so what i'm asking is 1) is this a good motor that has some time left with its age? 2) is it easy to work on/maintain? 3) what is the combo of motor and controls worth?
any input is greatly appreciated.
Thanks
 
is this a good motor that has some time left with its age?
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Only if it is in good mechanical shape and has good compression. This motor is only 35 hp at the prop and is known for crankshaft breakage if run above rpm range.....
[QUOTEis it easy to work on/maintain?][/QUOTE]
On a scale of 1-10 with 1 being easy and 10 extremely hard its a 4
what is the combo of motor and controls worth?
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Depends on your location, here where I am anywhere for $300-$600..
http://chattanooga.craigslist.org/search/sss?query=mercury+outboard&srchType=A&minAsk=&maxAsk=1000
 
thanks Faztbullet,
The owner claims it has strong and equal compression on both cylinders. he also said it shifts in and out of gear fine. is there any quick test or things to look for when i go and look at it? thanks
 
Remove any covers and look closely at the wiring for cracked insulation. Run the engine for five mins. in a trash can mounted to a sawhorse and then check compression--beg, borrow or buy a cheap gauge--test both cylinders. Look for near equal #s over 100 PSI. A 6 HP engine is plenty of power for your boat--35 prop HP is quite alot for a 13' boat so take it easy until you get used to its power.
 
Thanks guyjg!
I have a compression gauge, I have never done a tit on an outboard though. What is the method for doing so? also if the wiring is cracked can't it be replaced? Does this motor have an inlet for a hose to run it out of water? Thanks again
 
Remove both spark plugs and screw in the gauge hose until snug. Pull the rope quickley and read the gauge. Wiring can be replaced...use the same wire gauge and color codes, tin the bare wire ends w/solder--easy to do--use shrink tubing on the wire connectors after soldering the wire to it and crimping it. Seal the connection w/liquid rubber and never have a corrosion problem. Crimp on connectors can be purchased w/shrink tubing attached. Connect a set of ear muffs to the leg if they will fit or stick the leg into a 55 gal. drum garbage can of water.
 
It's worth what you are willing to pay for a 30 yr. old OB. To me it's a $100 no testing or questions asked cash-N-carry OB. Or a $200-250 test and buy OB. It's winter time...a bad time to sell an old OB. I would offer a lowball visible cash in your hand price.
 
RUN away from that clunker! Especially for a speed boat. They are powerless compared to a "good" motor and love to snap their crankshaft at the top. Ignore it!

Lots of 4 cylinder mercs out there. Much better engines.

Jefff
 
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