In order of my interest, here's how I do boats:
Inboard/outboard powered boats.
Sailboats.
Canoes/kayaks.
Anything with an outboard engine.
That said, I've got a potential deal on a neat vintage aluminum runabout (like a fishing boat but with console controls and windshield...~'58 vintage) that has an outboard with "no spark."
In my experience, outboard engines are tempermental and hard to figure out. So, I come to you all to straighten me out and tell me I need to get this $500 deal because they're actually quite simple. ;)
There can't be anything magic about outboards, right? Multi-cylinder 2 stroke, water cooled engines...
The one in question is a Mercury 40 HP...maybe a "401"? I'll have to research deeper.
Should I run far away from vintage outboards, or can it be reliable?
And by reliable, I mean, My 2 daughters and I on the Missouri-freaking-river reliable.
Clem
(I'd rather get a cheap in/out boat, but they're typically fiberglass, and I like the idea of a metal boat with the trash floating in the Big Muddy)
Most of what has changed about outboards over the years is external. They have redesigned ports and reed valves (much like automobile engines' head designs have been updated) for more efficient power production. That basically manifests itself as somewhat superficial operational differences; easier cold starts, more power per displacement, less weight, etc.
But even back as far as the old white-cowled mercs still have parts available pretty easily; bearings, cranks, pistons, rods, rings, the works.
There is a great chance that the aluminum boat is really sturdy. I have a '58 Sea King runabout that I ran up until 1995 with a 62 Evinrude 10 hp and it was as reliable as can be. I upgraded to a 67 Johnson 20 hp for more speed, then eventually upgraded to a 92 Merc 25 hp to get electric start. But the boat itself is a model of strength. It used twice as many strake ribs as newer boats, had big strong gunnels, and the aluminum itself was twice as thick with rivets about an inch apart. Newer ones only have a rivet every 3 or so inches.
If its not getting spark, I would check the coils first; easy to change and cheap to buy. If its not the coil, I would check the stator under the flywheel. Usually its something simple since there isn't really anything complex in those old 2-strokes.
There are always lemons, but a good-running classic outboard is just as reliable as a new one. If it wants to be temperamental, its something about the tune or its just wearing out. A compression test will help narrow down ring wear. But, comparing an old outboard to a newer one is just like comparing an old chevy V8 to a new one: properly built ones that are done right will last just as long and be just as reliable. But if you're comparing an old survivor V8 with 200k on it versus a new V8 with 40k... you take your chances. But, the old outboard is just as likely a candidate for a reman as anything.
I guess what I'm saying is... old and new doesn't really matter concerning Merc outboards' reliability; its the condition of it that determines how reliable it is.
I don't know much about old Mercurys, but OMC motors (Johnson/Evinrude/Gale) in those days were famous for the coils burning out. If it's been sitting around for a while, make sure the water pump impeller in the lower unit is good (for that matter it's probably due for a general inspection and tuneup anyway.)
There are websites out there for vintage boat motors, you may be able to find some repair manual data online - besides Mercury, search on the word 'Kiekhaefer'. Karl Kiekhaefer was the founder of the company (as well as a motorsports enthusiast, he was involved in early NASCAR and the Pan American road race in Mexico.)
Cool to hear guys. Thanks!
The seller actually offered to do a compression test to show the engine was good sine it didn't have spark. Say's he's tired of messing with it. I understand that feeling. Eventually, I'll certainly be tired of messing with it too ;).
I figure, given my intended usage, I'd be best to have a little backup outboard as well. Maybe a 10 hp or less, recoil start and tiller steer...just in case. Never hurts to have a backup plan, lest we drift to the Gulf... ;)
BTW, it's supposedly a '58 Lonestar in 14'. It seems there may be more than one model...I'll have a look at it and see what it's like, but I sure think it could be a fun toy.
Clem
ClemSparks wrote:
Say's he's tired of messing with it. I understand that feeling. Eventually, I'll certainly be tired of messing with it too ;).
The two happiest days of a boat owner's life are the day he takes delivery and the day someone else takes delivery. 
Touch the wiring under the shroud. Most of them are dissintegrating and badly corroded, leading to all sorts of permanent running problems. If it were just the harness, that'd be an easy home made fix. But it's usually the stator wiring and such, and you can't fix that.
I hate to pull a Hess, but remove the merc, attach the cheapest used Tohatsu you can find. I bought a boat for $500 with an unmaintained 70hp tohatsu motor. I never winterized it or sta-billed the fuel, just rinsed the salt water out of it when we came home. It would sit all winter and start on the first crank, and purred like new the whole time we owned it. At 15 yrs old it is still running, out into the Atlantic 2-3 times a week, and probably on the plugs it left the factory with.
foxtrapper wrote:
Touch the wiring under the shroud. Most of them are dissintegrating and badly corroded, leading to all sorts of permanent running problems. If it were just the harness, that'd be an easy home made fix. But it's usually the stator wiring and such, and you can't fix that.
Can't fix something? That will pretty much seal the deal...can you explain more?
The stator...that's the windings around the shaft (crankshaft?) that generates the electrical power, right? Similar to an alternator...
Can one not replace the stator, or is it cost prohibitive are new stators non existent?
The going prices for used outboards lead me to believe that I would probably have to triply my investment on the boat to come up with a different outboard for it...so I don't think I'll go that route.
Thanks again, all, for the discussion!
Clem
But it's usually the stator wiring and such, and you can't fix that
Disagree, fox. Clem - Pull the flywheel off and you'll see something like the picture below. That is a Johnson 9.9, but all of those parts are replacable. It works because there is a magnet in the flywheel that passes over those coils. Cheap, easy, right on top, no-brainer for a GR person like yourself.
Clem,
Virtually every part is available from Mercury, at a typically expensive price. There are virtually no aftermarket alternative replacements.
Be it the ignition winding, the charging winding, the ignition module (Thunderbolt, etc). They all suffer from the problem, as the problem starts in the wires.
The wiring insulation breaks down. Corrosion starts on the copper, and walks its way up into the components themselves. More than once I've thought I could fix it by cutting out the damaged wiring, only to find the corrosion had traveled all the way up into the components themselves.
Generally this corrosion does not render the component inoperable. It does cause the component to work poorly. The degree varies greatly.
Don't break the deal on my comments. Investigate the powerhead and decide yourself.
I do appreciate all the advice folks.
Turns out, I was mistaken on the model. It's a 1977 Mercury 700, which I surmise is 70 horsepower (not the 40 I think I stated originally).
This little 14' runabout would probably scoot along nicely with that engine, I suppose!
I really have no business buying a boat right now, but that never stopped me before...
Looks like the iboats forums has some good info on "ohming-out" stators and such. I'll probably study up and look closely at the boat and see how things really look.
Thanks again for the discussion!
Clem
