Merc 60HP & 65HP - Prone to Overheating??

[turtle1173]

Hi all,<br /><br /> A local mechanic told me recently to stay away from mercury 60 & 65 HP motors because they had a flaw in regards to the cooling system. He said that the design was flawed and didn't allow for adequate cooling.<br /><br /> Is this just his experience or is there anything to this?<br /><br /> It just so happens that I have an opportunity to get a great deal on an '88 60HP. But I'm feeling a bit leary now.<br /><br /> Is it true that the 3 cyl. mercs only have 2 carbs? How does that work? Are the 3 cyl. motors as good as the 4 cyl. or more problematic?<br /><br />Thanks,<br /><br />Shane

 

[Maximerc]

Re: Merc 60HP & 65HP - Prone to Overheating??

YEARS ago my dad had a 65 HP 3 banger 1971 or 70 ..... we had it for two years and it seized.. when it was rebuilt there was mud found caked in the water inlet.. ran for many years after that two carbs as I rember??

 

[snapperbait]

Re: Merc 60HP & 65HP - Prone to Overheating??

Cooling system flaw? Not that i'm aware of...<br /><br />It is true, only two carbs, works just fine...<br /><br />Love my 89 60hp 3 cylinder... Best running/easy to start motor I ever had... Only gripes I have are, #1, for a 60hp that is smaller than other 60's ( johnson/evinrude, ect.), it sure seems heavier.. Gripe #2, prop is small due to the higer gear ratio in the lower unit, so it don't push a heavy boat as well as a johnson/evinrude... Aftermarket prop size selection seems so-so...

 

[turtle1173]

Re: Merc 60HP & 65HP - Prone to Overheating??

I guess I would like to know "how" 2 carbs feed 3 cylinders? Are the carbs harder to setup than a 'normal' system?<br /><br />Thanks again,<br /><br />Shane

 

[rodbolt]

Re: Merc 60HP & 65HP - Prone to Overheating??

hello<br /> the two carb 3cyl set up worked well but was a bit more complicated then the later force 70 3cyl one carb. the only "flaw" we ever noted and merc said NAH to wes the fact that as the cooling system wore it had a possibility to form a steam pocket at the top of the block and burn the topside of #1 piston. a cure was to drill and tap a hole in the top of the block and relocate the tell tale to the top and block off the middle fitting. what is amazing is that later 3 cylinders suddenly had the tell tale on top.<br /> its a good engine just do the cooling system maint every year regardless of hours.<br /> good luck and keep posting

 

[turtle1173]

Re: Merc 60HP & 65HP - Prone to Overheating??

So the tell tale water exited too fast so that the water wasn't getting all the way to the top cylinder? So this '88 would have that problem then? If so, that doesn't sound too complicated of a fix?<br /><br /> By 'cooling system wear', you are referring to the water pump wearing out, right? <br /><br /> I think I'm probably going to go ahead and get this motor. It is a great deal.<br /><br />Thanks,<br /><br />Shane

 

[turtle1173]

Re: Merc 60HP & 65HP - Prone to Overheating??

Rodbolt,<br /><br /> Would a water pressure gauge be a good idea on this engine? If so, what should the readings be?<br /><br />Thanks,<br /><br />Shane

 

[turtle1173]

Re: Merc 60HP & 65HP - Prone to Overheating??

Well, I ended up buying the 1988 60HP Mercury ($650). I picked it up yesterday. I haven't run it yet but it looks great and seems to have been well taken care of.<br /><br /> I also wanted to add that this '88 model does have the tell tale coming from the top of the block. Needless to say, I was pleased at that.<br /><br /> Now I've got to figure out how to hook up the controls. Then I'll be good to go try her out.<br /><br />Shane