Merc 60 - suggestions for re-building the head?

JoeMan

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Jun 29, 2006
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322
Just got bad news from the mechanic. Took him the plug from the top cylinder of my 1987 merc 60, it had what looks like melted aluminum on the firing tip of the plug. He says the head is shot, and that'll be 1,800 clams to re-build. I don't have the money. This motor was bought used, and there is no recourse to go back to the seller. I just restored an old boat, put the motor on, it ran great for a few trips out, now this. I am NOT a boat motor person. I know how to mix oil and gas and change spark plugs. I am a fairly mechanical guy, so please tell me if there is a way for someone who's NOT done it before to buy a kit and re-build the head.
 

JoeMan

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Messages
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Re: Merc 60 - suggestions for re-building the head?

JoeMan said:
Just got bad news from the mechanic. Took him the plug from the top cylinder of my 1987 merc 60, it had what looks like melted aluminum on the firing tip of the plug. He says the head is shot, and that'll be 1,800 clams to re-build. I don't have the money. This motor was bought used, and there is no recourse to go back to the seller. I just restored an old boat, put the motor on, it ran great for a few trips out, now this. I am NOT a boat motor person. I know how to mix oil and gas and change spark plugs. I am a fairly mechanical guy, so please tell me if there is a way for someone who's NOT done it before to buy a kit and re-build the head.

Let me rephrase the question and add some information. The motor had hook and pin style plugs in it when we received it. It started and ran fine, I took it out for one 20 minute trip. It was running hot to me, so I took it in. The mechanic told me that 140 temp was fine, no overheat problem, but that we needed flat top plugs in it instead, and indeed, the book calls for flat top...so we put them in. The first set of these plugs were in for the next trip, and that's when the plug in the top cylinder became aluminum coated. I replaced the plugs again, and went again. There was no aluminum this time, but the plugs were a bit oily, and the motor bogged down badly after 15 minutes, just like it did with the previous set of plugs when it coated the top plug with aluminum. Having seen the coated plug, the mechanic said the head needed re-building. Now then...perhaps that's enough info for one of you pros here on iBoats to tell me if you agree with his diagnosis, and if 1800 is reasonable to rebuild the head...or perhaps if there is anything else I can do?
 

AMD Rules

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Sep 23, 2004
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1,707
Re: Merc 60 - suggestions for re-building the head?

That motor doesn't have a head. The cylinders are blind holes, and if the cylinders are scored badly the block will require re-work or replacement.

Did anyone do a compression test yet?

Did anyone pop the intake covers off to inspect the piston rings/skirts and cylinder walls?

Can't judge the value of the 1800 quote without knowing for sure what the scope of repair is. If the quote simply says "rebuild head @ 1800 dollars" then move on to the next mechanic.

For a complete overhaul, including rebore oversize, re-ring, new bearing seals and replaceables throughout.... 1800 wouldn't be completely unrealistic,

A rebuilt powerhead off the shelf can run well over 2k.

Just my 2 cents..
 

JoeMan

Petty Officer 1st Class
Joined
Jun 29, 2006
Messages
322
Re: Merc 60 - suggestions for re-building the head?

AMD said:
That motor doesn't have a head. The cylinders are blind holes, and if the cylinders are scored badly the block will require re-work or replacement.

Did anyone do a compression test yet?

Did anyone pop the intake covers off to inspect the piston rings/skirts and cylinder walls?

Can't judge the value of the 1800 quote without knowing for sure what the scope of repair is. If the quote simply says "rebuild head @ 1800 dollars" then move on to the next mechanic.

For a complete overhaul, including rebore oversize, re-ring, new bearing seals and replaceables throughout.... 1800 wouldn't be completely unrealistic,

A rebuilt powerhead off the shelf can run well over 2k.

Just my 2 cents..
Thanks for the reply. No, no compression check yet. Whether one cylinder is much lower, or whether they're all the same, what is that telling me?

No, nobody has taken the intake covers off. I would be willing to do this, but not sure what I'm looking at, unless it's obvious. Is there anything in particular that I need to be extra careful with as I remove the intake covers? Thanks again, I sure appreciate it.
 
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