1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

[MercMark]

I just got in touch with my loacl marina and supplier of Merc parts.<br /><br />I found out that it could cost me up to $1400 Can to rebuild my engine. For this price I am likely to find a used one that runs.<br /><br />I know that in the manual it says to replace a lot of parts no matter the condition. I was wondering what the actual real world says about this. The parts list he gave me included a lot of stuff. Four pistons, gasket kit, reed kit, top main bearing, bottom main bearing,.... etc...<br /><br />I asked if he has pistons available individually, since the cost of a piston is $220 Canadian.<br /><br />My engine will run on three cylinders now but there is zero compression in cyl.2. <br /><br />What are this community's opinions on replacing only one piston and other parts on an as needed basis. (and specifically for parts that the manual says to replace regardless of condition).

 

[MercMark]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

^

 

[Solittle]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

Depends on how lucky you get & how long you want it to last.

 

[sharkcat]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

If only one piston is damaged just replace that piston & re ring the others if they are ok.Obviously things like gaskets etc will need to be replaced but if other parts are still ok you can get away with reusing them BUT they may not last as long....With regard to parts try<br />www.theshadconnection.com<br />they sell parts pretty cheap also if you need bearings & seals try a bearing supplier.Here in Australia I needed drive shaft bearings for my 60hp merc $92.00 Aus for genuine $26.00 Aus at a bearing supplier.Hope this helps

 

[dkondelik]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

there are many opinions on this subject. for the greates relaibility, go by the book and replace all of the goodies. BUT,..... if plan "B" is to purchase a used engine (of unknown internal condition) , i think that you'd be ahead of the game, doing as suggested above. rework the bad cylinder and replace with appropriate "over-sized" piston. <br /><br />if you do the rebuild yourself and take the block to a machine shop for the "overbore", you can probabaly do it for a few hundred bucks ($US). Roughly $100 for the "over-boare", $150 or so for the piston and a hundred or so bucks for new rings for remaining pistons and gaskets.<br /><br />Good Luck

 

[ledgefinder]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

The Merc factory manuals says its OK to replace just one piston, and that the replacement oversize pistons are manufactured to weigh the same as original size so as to make that possible.

 

[sharkcat]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

bump

 

[Canadian mercury man]

Re: 1970's 85hp Merc Cost of a rebuild and The manual vs. Real World

i am currently having a 1971 mercury outboard rebuilt here in thunder bay, ontario. the cost will be 1500.00, new pistons, rings, plugs, gaskets, a hone job on the cylinders, new fuel pump and all the dam labour. I looked at new engines....used engines and for 1500 bucks i know what i end up with and i am not buying someone elses problems just to do a re-build a season or two from now on a used engine. I looked at all the ways around it....economically it was the best choice, as for reliabilty...well i know my rebuilt 70 will outlast me now