Mercurys

[andrewkafp]

I see a lot of posts on here relating to Mercs.<br />How do older Mercs rate compared to other Mfrs?<br />Were there good and bad years or no of cyls ??<br />I know everyone has likes and dislikes and I've seen a lot of negativity towards some brand names.<br />I own a 4 cyl Merc made between 1979-82 and it seems to be pretty good for it's age.<br />American made products have a good reputation, but the Japs have also been making OB's for a while too.

 

[graddy]

Re: Mercurys

All outboards have the potential to be a good motor. Its come down to who owns thew engine and how well they maintain them. Some people treat the outboard engine like its there car they drive everyday and those are the kind of people that have trouble and blame the running problems on the manufacture.

 

[Moving Target]

Re: Mercurys

I would by any brand outboard except a Force. They all make good motors.

 

[lakeman1999]

Re: Mercurys

I have a 1994 force 70hp on my 20' pontoon, that I am a lot happier with than I am with my 1994 johnson 40hp that is on my 14ft alumacraft fishing boat. I wish I never would have purchased the 40 hp johnson, I do know that johnson is a good product (as are probably all motors out there today, including forces) but I have been upset with this one from day one, and have had my share of problems with it.

 

[12Footer]

Re: Mercurys

Lakeman and I are on the same page. Force are cheap,good old-tech motors that will run forever, if treated right. They run filthy, but run and run and run. You gotta maintain them, and they require a greater degree of time to maintain properly. Enough of Force, as that was not your question.<br />Mercs have the most R&D over thier illustrious history,than does any other single manufacturer,past or present, with the present exception of Bombardier, which I've heard is considering selling the Johnnyrudes off again. I sure hope OMC finds a good home and soon. They are some good motors (late 90's Q/C problems not withstanding).<br />Mercs have a great racing history too.<br />They have had thier "engineer keg party" designs too,like the 60's vintage 65HP,that you have to take down to the stinking block to get the carbs off!!!!!!!! Ehem,,,,I'm ok now, where was I? Oh yeah, design.<br />Thier greatest design IMHO, is thier old inline 4's and 6's, effectionately called "tower of power", as thier labled HP is highly underated.<br />They boogie, and are simple in design.<br />I never met a merc I didn't love, 'cept for the 1966 65HP mentioned earlier. It's an inline 4, but whoever designed it was drunk, and not thinkin about the poor schmuck that left gas sittin in the carbs over a long hot summer.

 

[andrewkafp]

Re: Mercurys

^^

 

[NathanY]

Re: Mercurys

That is a beautiful motor you have there. It will be a great motor for you. However, you will need to make sure that the carbs stay clean on that thing. If not, you could get a little lean, and then CA-BLOOOOOEY. Mercs of that era are very sensative to that kind of thing. Its all about regular maintainence.

 

[FredM]

Re: Mercurys

Hi andrewkafp, I've got an '81 2 cyl 18hp blueband which starts and runs as good as the day it was born. The local service agent says the motors from that era are really tough. He showed me a 20hp they were servicing that belonged on a tinnie off a cray boat - it had a tough life and was knocked about but ran sweet. <br /><br />My 18 seems to have a lot of grunt for it's rated hp. I have it pushing a beamy 13' tinnie runabout (got chequerplate floors screen and canopy), and with a full load of fuel, 3 hp aux, safety gear me and my mate, the dog and all our stuff can keep up with his kids in an 11' Stacer with a 15hp Suzuki. or maybe <br /><br />I was determined to beat the ankle biters so I threw the dog out when we were neck n neck - man can she paddle! -with a rope in 'er teeth she pulled us a length ahead to claim victory. Dogs name's Mercury too , but doubt she'll be around as long as the black one on the back!

 

[andrewkafp]

Re: Mercurys

Fred<br /><br />My goodness... a fellow Aussie ....(Well almost) jkg <br />My Merc has a Austrailan Serial no 8055898.<br />Very hard the pinpoint the year,as the Aus numbers are different from the USA made product.<br />The closest I got is in the Clymer, where it refers to a 1978 as a Merc500. The guys on here have said that Bluebands finished in 1984.<br />So it's between 1979 and 1982.<br />But the prevoius owner took good care of it and spent a fortune on new switchbox, stator rectifier, impeller, oils and plugs etc etc.<br /><br />Yeah.. Nathan , how would I go about keeping tads on that Rich/Lean scenario ? I use premix @50:1<br />and sometimes more like 45:1<br />She tends to blow a bit of black petrolly smoke when choked, but other than that, runs well when warmed up.

 

[FredM]

Re: Mercurys

Yep that's right my 18 blueband was redesignated a merc 20 in 1984 and sported the red band. The 18 I have has an American plate on it s/n 5918844 and the starter has an '81 date on it. BTW do you decarb yours?

 

[andrewkafp]

Re: Mercurys

Not Yet Fred, only bought her in March. Fitted a Suzi 6hp twin auxiliary and then took both out for a run once only.<br />Just starting to get "Obsessed" with this Outboard stuff and found this site to be great.<br />The Yanks (in a nice way) are very knowledgable on Outboards and I'm learning all the time.<br />Nathan mentioned "Running lean" which I interpetted as more air/less fuel.<br />I also know that carbon builds up in 2 strokes reducing the exhaust size and choking up the motor. What is the proceedure for De-Carbonising and what are the benefits ?

 

[FredM]

Re: Mercurys

Running lean means that the air fuel ratio has too much air. This results in a higher combustion temperatures in both 2 and 4 strokes with the potential to burn pistons and more importantly reduced crankcase and cylinder lubrication in 2 strokes. <br /><br />You need to keep your fuel fresh to avoid varnish buildup which can block the passages and jets in the carb. Also a low float level will cause a lean condition. I also give the primer bulb a pump every once in a while to keep the carb full. This prevents the the fuel from evaporating from the carb and leaving gummy deposits. <br /><br />Have a good look at your plugs when you take them out, they should be clean with no deposits and a tan colour. The Clymers manual has a good section on plug conditions and causes. - Cheers<br /><br />PS I think the jury's out on decarbs. If your compression is good just make sure you use a good TCW-3 oil and mix your own 50:1, give the motor a good run at WOT when your out and especially if you've been trolling or idling about.

 

[andrewkafp]

Re: Mercurys

Thanx<br /><br />Interestring stuff..<br /><br />My comp is around 110 in all 4.<br />125 at another repairer The concensus is to run the motor out of fuel before storing (Which I do) and keep the fuel fresh.<br />The debate is "How long is fresh" ??<br />I will keep petrol for no more than about 6-8 weeks but will regularly add to it. If not used before then I will dump it.

 

[FredM]

Re: Mercurys

Have a search on this site, there's a couple of good threads on here about whether to run carbs dry or not and how old is old fuel,storage and stabilisers etc.<br /><br />As far as your comp goes the tests vary from repairer to repairer, equipment used, motor hot or cold and whether the throttle was wide open or not. Main thing is to have all cylinders within 10% of each other. See ya