As Engines go; How would you rate a 1978 850?

[SeaKaye12]

Hi All,<br /><br />1978 Merc 850 that's seen little use, but was put up and left setting for perhaps 20 years. Four Cylinder, fresh water only.<br /><br />Is this an engine worth fussing over? I've been reading posts here for the last several days...<br /><br />I would like to know where this engine stands? Reliable? Weak points? Strong Points? <br /><br />Should I consider it a "keeper"? <br /><br />I guess it's a tough question...but I don't want to waste the energy/money if the general consensus is that this motor (by design etc.) is not worth the effort.<br /><br /><br />Thanks, Chuck

 

[JasonJ]

Re: As Engines go; How would you rate a 1978 850?

It is worth it if you get it cheap enough. Odds are, a new water pump, and a good carb cleaning is all you'll need to do, and you will have an engine with very low hours and tons of life left in it. I would kill to get ahold of an outboard that was used 7 years and then stored, unless the thing had blown. Good luck....

 

[SeaKaye12]

Re: As Engines go; How would you rate a 1978 850?

Yes; I'm thinking positive that it shouldn't need much.<br /><br />Reading forums like this can get scary...it seems that everyone out there either has no spark, no compression on cylinder #3, overheating issues or some combination of all these and more ailments...<br /><br />Of course; people don't post here if their engine is running fine; they only post here if they are having problems (generally) so it's understandable that the forums are this way.<br /><br /><br />Every outboard that I have owned performed admirably for me, with only the usual DIY maintenance. Hopefully this Merc will be no exception.<br /><br />As for the price...the motor ,boat ('78 Thunderbird, and trailer were free...)<br /><br />Chuck

 

[jimmbo]

Re: As Engines go; How would you rate a 1978 850?

They didn't make an 85hp in 1978. 1977 was the last year for the 850, in 78 it was rerated 80hp and a inline 6 was offered as a 90hp.

 

[SeaKaye12]

Re: As Engines go; How would you rate a 1978 850?

Hmmm...I guess that explains why on-line prop-selectors come up blank for a '78 Merc 85...<br /><br />The boat is an '78; I just assumed the engine was the same year.<br /><br />My Engine is Model # 18507; the serial number is 04721196. I'm taking these from the original "MERCARD" warranty/ownership card.<br /><br />Is that a 1977? Thanks for the info...I'm sure that I'll be needing all the help I can get <br /><br />Chuck

 

[Motor Boater Bill]

Re: As Engines go; How would you rate a 1978 850?

The serial number should also be on a plate mounted on the outside of the motor--worth checking to make sure it is the same as what's on your paperwork--motors get switched on boats. Looks to be a 77 with the serial number you gave:<br /><br /> http://www.pfs-ware.com/kwast/merc_serial_number_reference_gui.htm

 

[Scali]

Re: As Engines go; How would you rate a 1978 850?

The way some boats & motors are sold & rigged it's not uncommon for new leftover engines to be packaged & sold new current model boats .<br />I bought a New Carolina Skiff few years ago that dealer hung a new 90 Johnson that was a 2 year leftover, 2 years difference in boat & motor but both new..

 

[timmathis]

Re: As Engines go; How would you rate a 1978 850?

Mine was A 79 with A 75. you can't go by the year of boat!

 

[timmathis]

Re: As Engines go; How would you rate a 1978 850?

I Think you will be happy with it. For free.

 

[Motor Boater Bill]

Re: As Engines go; How would you rate a 1978 850?

Free...well, it's kind of like a free puppy, isn't it? The cost is all in the upkeep! <br /><br />Still, you can't argue with the price and you can save a bundle working on it yourself with the help you can get here!

 

[andrewkafp]

Re: As Engines go; How would you rate a 1978 850?

A 77 and 78 looks different (Cowling paint).<br />Should be able to tell by that. Otherwise pretty much the same.+<br /><br />1978<br /> http://www.myfishingpictures.com/watermark.php?file=527/141379merc.jpg <br /><br />1976-77<br /> http://www.myfishingpictures.com/watermark.php?file=527/14131976.jpg

 

[SeaKaye12]

Re: As Engines go; How would you rate a 1978 850?

I'm bumping this thread because it sort of got off track.<br /><br />My original quest was to get opinions as to the quality of the over-all design of the Merc 850.<br /><br />Merc has offered similiar HP engines in 3,4,and 6 cylinder configurations. How does mine (4 cyl) stack up in comparison?<br /><br />In general; are the in-line 4's of that vintage thought of as strong? reliable? smooth running? worth keeping?<br /><br />I was reading Clam's comments on his e-bay page regarding the in-line 6's merits...I wonder if similiar comments apply to the 4's?<br /><br />I'm sure Merc has made some dogs..I'd like to know where mine falls in the range of good vs bad...<br /><br />Thanks for reading, Chuck

 

[Chris1956]

Re: As Engines go; How would you rate a 1978 850?

SeaKaye, I received a '73 850 as a hand-me-down. It had been run without oil twice, and the gear oil was never changed. I tore it down, honed the cylinders and put new rings into the sorriest-looking pistons I have seen in a while. It ran fine, although the LU was shot. Not too much power on the low end since it's compression was bad.<br /><br />The only negative I have is that the four cylinder motors did not run as smooth as the threes and sixes. I always liked the low profile and compactness of the design. It was always descent on gas, although I had it on a light 16' boat and was afraid to open it up.

 

[timmathis]

Re: As Engines go; How would you rate a 1978 850?

There great as Tony the tiger said!! I know many people that run the 4s and are a verry good motor!<br />Myself I have a inline6 merc. Here in S.C. you still see a lot of old Mercury 3,4 & 6s The 850 is a good choice in OB's so good luck be safe and enjoy, Tim Mathis