Advice on preparing my new to me Mercury 80

[brewern]

With all the great advice from this forum, we recently purchased our second boat. It's a 17' 1986 Chaparral Runabout with a 1983 Mercury 4 Cylinder 80HP .
It had been sitting about 3 years in a garage without running, but with a little starter fluid and some cajoling, it sprang to life. It was smoky at first, and running a little rough as expected, but it does run fine, and I rev'd it a little. After idling several minutes the smoke cleared up and it was running a little better. The water pump seems to be working good.

So, now I really need to get to know this engine. Can anyone tell me the link to the proper engine manual, and what steps I should consider next?

I'm thinking an oil change, spark plug change, and clean the carb(s). See, I'm not even sure how many carbs it has.
I also learned that the wiring on these older Mercury engines are pretty bad, and after looking at mine, I have to agree. I need to learn how to do that. DO I splice into the old wires where they are still good, or buy new? Or what? Any advice would be welcome.
Oh, also, there are no instruments on the dash which really surprises me. Can I/Should I install at least a temperature gauge?

And what else should I be considering before we hit the water?

Thanks as always!

 

[brewern]

Re: Advice on preparing my new to me Mercury 80

Got the carb rebuild seals in todady. Gonna remove carb right now, and start the rebuild. If the float is good, we'll have it back together soon.

Any advice on my questions above?

 

[carholme]

Re: Advice on preparing my new to me Mercury 80

What is the s/n of the engine?

Gerry

 

[glenn property of pam]

Re: Advice on preparing my new to me Mercury 80

try not to use starter fluid as it contains no oil and after 3 years the engine might have been lacking full protection (spray bottle with premix works better). whats done is done so no need to worry about that now.

water pump realy does need doing. i know it works fine but why chance it.

electrical: the boat and the motor are on 2 diffrent circuits so other than changing a terminal ring or clip i would leave the motor side alone as its working. The boat side may need repairs as required.

gauges: if the boat has a alarm then you realy dont need gauges. You can install a tiny tach or something like that on the motor for testing or you could design a dash it your own personal choise

 

[emckelvy]

Re: Advice on preparing my new to me Mercury 80

Nice looking rig! One comment, though on the trailer: the boat is way too far back on the trailer and probably is rear-heavy. The back rollers should ride on about the last inch or so of the transom. With the rollers so far up (boat too far back), the rollers are riding on a less-supported area of the hull, over time this can distort the hull, causing what is called a "hook". Poor handling will result.

Can't see in the pics how long is the trailer tongue, but if long enough you should be able to adjust the winch stand to move the boat forward. It'll give you a little tongue weight as well, which is important for proper handling while towing.

Back to the motor, if you have deteriorated wiring in the engine harness, it can be repaired, depending on how bad it is.

If the wiring insulation is bad, but the wires aren't all green-n-nasty corroded, you can dress the wires with some heat-shrink sleeving.

If the copper wiring is shot as well, you can cut it back to good wire, and splice in replacement wiring. I'd recommend an uninsulated crimp-type connector, followed by soldering for the most solid connection. Cover the bare connections with a very thin coating of electrical tape (or the liquid insulating "tape", even better), followed by an overlapping sleeve of heat-shrink sleeving.

This makes for a very clean, electrically-sound repair that should last a long time.

You can get wiring and sleeving in the various colors to match exsiting wire colors, for a more "professional" repair.

Note that if the wiring is bad, no matter how far back you cut, you'll need to replace the internal harness. These are available from CDI Electronics but ain't cheap! (over $100).

I'll also vouch for water pump replacement, cheap insurance, you can get a full kit for well under $50 and the powerhead is worth a lot more than that! Or more likely only the impeller needs renewing and an OEM impeller from Merc retails for less than $25, and can be found online for less than $20.

Re: gages, a water pressure gage is a nice addition and good indicator of cooling system health. Kits are readily available here at iboats and lots of other places. There already should be a tapped hole with a plug in it, back of the water jacket cover (around the spark plugs), for installation of a pressure gage fitting (1/8"-NPT). If not, likely there's a pad where the hole can be drilled & tapped.

Same thing for a tach, very handy to know rpm so you can optimize your prop selection. Your control box probably has the tach connector on it, and any marine tach that runs off a 12-pole alternator will work fine.

HTH..........ed