Questions about outboard boat engines

railsplitter

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I'm looking at purchasing a used pontoon boat. The boat itself is 17 years old, but my only concern would be the engine. It has a 125 hp mercury 2 cycle engine, but I'm not sure if it's original to the boat. I've never owned a boat before, so would greatly appreciate any pointers anyone has or things to look for and/or questions to ask specifically about the engine. The dealer who has it says that they go through the engine and perform any required maintenance and tune-ups before putting it up for sale. They offer a 90 warranty with purchase.
 
The dealer who has it says that they go through the engine and perform any required maintenance and tune-ups before putting it up for sale. They offer a 90 warranty with purchase.

This is good. Make sure you can use it enough to make use of those 90 days. Then run the heck out of it. Sometimes engines get replaced due to "ah crap" stuff. Check the age on the engine plate near the transom mount. A 17 yo 2 stroke isn't bad.

Have them provide paperwork of all work checked/done with compression test notes. Also, have them change the fresh water impeller and outdrive oil.

You personally inspect the anodes and propeller (turns with no noise or grit feel). On the test run (in the water, not on muffs) listen to it shift from N to F and then from N to R. It should clunk but not make multiple clunks before engaging (move the shift with purpose, not timid but don't hit it like @Chdamn in his basement). Also, in N and at idle the prop should not turn.
 
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I know the older Mercury's aren't known for reliability. Also, that seems like a LOT of motor for a Pontoon. Normally they run a 40-80hp engine, but a 125 would make it scoot right along and pull rafts and other inflatables.
With that said, some things I've learned over the years about boats (aside from don't ever do it again) are:

Outboard > I/O
Always get compression checked on them. ALWAYS. Ask the dealer for a report on compression.
Price parts like coil packs. You'll have to change them eventually.
 
I am by no means a mechanic. More the guy that writes the check. But I have done about everything that can be done to a used outboard. And most of that work was done on the water or a dock. So, that being said...do as much due diligence as you are able. Test it well those first 90 days. And buy a good manual and tools so you'll be able able to get off the water when the time comes.

And never forget a spare prop, cell phone and a coulple decent oars. You'll be amazed how far you can row a pontoon boat when you are motivated.
 
I am by no means a mechanic. More the guy that writes the check. But I have done about everything that can be done to a used outboard. And most of that work was done on the water or a dock. So, that being said...do as much due diligence as you are able. Test it well those first 90 days. And buy a good manual and tools so you'll be able able to get off the water when the time comes.

And never forget a spare prop, cell phone and a coulple decent oars. You'll be amazed how far you can row a pontoon boat when you are motivated.

I'd love to hear the story behind this sage advice.
 
Be sure to go over the trailer as well....Tires, bearings ( Bearing Buddy's) wiring harness/ pig-tail ,
running lights, brake lights and turn signals, hitch and safety chain and hitch size/ height compatibility....
Ask seller what accessories ( if any are included) are included in price. Little incidentals i.e.; PFD's, horn, fire extinguishers , anchors, batteries, etc. can add up quickly.

Remember the old adage.... 'A boat is an ever-deepening hole in the water that you pour money into......:(
 
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I'd love to hear the story behind this sage advice.

There are many stories. My first boat was an aluminum runabout made sometime well before I was born. The metal was so thick you could run into docks at about 20 mph and not dent it. The engine was an old Merc of unknown age and hours. There have been several boats, breakdowns and repairs since those days. I won't clutter the thread with my boating experiences. They are likely typical of anyone that has spent enough time on boats.
 
If it is an optimax, run away. If it is a carbuerated two stroke, get a compression check and go from there. Like cars, they all have their quirks. If you are serious buyer and have little experience with boats in general, I would take to another mechanic and pay for a second look. Parts and repair can get expensive quick.
 
Check the pontoons and decking, the pontoons could have corrosion, 17 years out in the weather could have rotted the deck. As for the motor, compression check, impeller/oil change is a good start. Confirm it hasn't been in salt water either.

Boats are fun but always a money pit.
 
I'm surprised no one has mentioned the two happiest days of a boat owner...

The day he buys it and the day he sells it.


I have many fond memories of days and nights out fishing in a little 8' Sears Gamefisher Deluxe with a little Mercury 9.8. It had oarlocks and hours at a time were spent rowing and drift fishing
 
Livin in the keys you had to have a boat. I went through several and all with outboards.
Salt water will kill it if you give it even the slightest opportunity. And I used to keep mine in the water a lot so I'd get off work and just hop in and zip around like an idiot.
It was great.
So you now have another woman that demands constant attention. But all she ever really needs is plenty of fresh water and wd40. If you can get used to that you're good to go.

@Ronsc mentioned the trailer. I've had as many problems with the trailer as the damn boat itself! And I had good trailers. So first off, common size stuff and spare everything. I even carried a spare 1" spindle around. A smoked spindle is the 2nd worst thing that can happen when towing a boat trailer, with the first being the boat coming off.

But beyond all the speedy ones an such, my 20' pontoon with a 50 mercury was probably my favorite. I would have that boat again.
And girls. Girls love pontoon boats. Every single girl on earth ever will go for a ride on a pontoon boat.
 
Get an outside mechanic to check the engine and do a compress test on the power head and have them pressure test the foot. Also, make sure the motor is charging the batteries. Most likely the selling dealer change the oil in the foot. Check the fuel lines to make sure they are not rotten from running gas with ethanol.
GET AN OUTSIDE MECHANIC TO CHECK THE ENGINE. That is worth repeating.
 
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