'84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

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MAtkins

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I *think* I ruined my heads.
I think I warped them by heating then cooling to remove snapped off bolts.
I'm still not really sure.

They're also just a bit scored up.

So I'm seeing heads on ebay that 'look' liked they'd fit but i don't know if they're really compatible.
Would heads from any of the other V6 motors work correctly?
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Outboard motor heads warp with time !!-They all do.---Just how much is the warping.-------They can usually be fixed with a piece of glass and valve grinding compound.---Simple methods work !
 
Faztbullet

Faztbullet

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Take to a machine shop and have milled, you can take up to .030 off without hurting anything....that motor should have the "hemi" style chambers..
 
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MAtkins

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Thanks for the replies!

I know what heads are listed, I just wondered if you can use different heads (like from a '79 175HP or a '95 135HP).
I'm not sure the heads are warped I just suspect that they might be.

I *really* don't want to send them back to the machine shop 200 miles away.
I live in Orlando. There are no outboard machine shops here (hundreds of lakes & boats but . . . ).

Racerone can you elaborate on that technique?
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

All outboard heads warp with time !!----Just the way it is.---------Carefully scrape all the old gasket residue off.----Put the 2 heads together and look between them at a light.----You can use a feeler gauge inbetween to get an idea of the amount of warpage.--------Find a piece of glass plate and spread some valve grinding compound on it.----Move the head on it in a random motion untill flat.
 
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MAtkins

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Thanks racerone.

If I do that with the heads don't I have to do it to the block too?
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

The block is a bit more substantial.------But to satisfy your curiosity you can use one of your refinished heads to check how flat the block is.
 
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MAtkins

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

OK thanks.

I just picked up some valve grinding compound & I've got a mirror just about the right size for the job, about 1/2" thick.
Looks like I'm going to do some grinding today . . .
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

1/2 plate glass should be flat I would say.----What you will see is the ends will rub first.--- Then gradually the contact will move to the center untill full contact is made.--Use a bit of varsol mixed with the compound to make it easier on your arms.--Be sure to wash off any compound with hot soapy water.----Put heads together and if it clamps a 1 " strip of newspaper at the centre you are good to go.
 
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Dukedog

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

MAtkins said:
Thanks for the replies!

I know what heads are listed, I just wondered if you can use different heads (like from a '79 175HP or a '95 135HP).
I'm not sure the heads are warped I just suspect that they might be.

I *really* don't want to send them back to the machine shop 200 miles away.
I live in Orlando. There are no outboard machine shops here (hundreds of lakes & boats but . . . ).

Racerone can you elaborate on that technique?
Click to expand...

Just n case you get tired of "rubbin'" on those things any 2.0/2.4 head from '83 ta '90 will work on your block. Preferably tha 2.0's. Tha cc area will be closer to tha same as yours. It will make a slight difference in compression but really not enough difference ta mater on a stock, everyday type driver...........Is "lapin' tha heads" a Canadian thing? Just never seen it done 'round these parts!
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Lapping with grinding compound is a common machine shop procedure.------Worked in a precision machine shop for a few years and that technique was common.--We supplied parts to the USA too.------This lapping is something the average person can do at home .------If there is no machine shop around it works like a charm..----Simple techniques are often scoffed at !--Even the factory manuals suggest refinishing the heads with emery paper on a flat surface.
 
Dukedog

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

I completely understand tha process and for a "finish" would be within reason but what if they need 20 ta 30 thousands taken off to make 'em straight? Just sounds like it would be "labor bound" for something more that just a finishing touch. If I wasn't so lazy I would give it a try but as long as FedEx, USPS, and tha Brown truck are still in service I'll stick with my machinist!...........
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

This sort of work should not be done by an outboard shop!-------You pass any expenses on to the customer.----This is for someone who wants to do the work themselves at home for a reasonable cost.---- The poster will let us know what the results are !
 
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wired247

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

It costs less than $50 to have a set of heads milled. Just sayin'.
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

The party stated that he is not near a machine shop.--He can do this at home for virtually no cost.----Some folks take pride in that.
 
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MAtkins

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

This motor is an '84 so yea, they're warped.

I'm using the technique and what I'm seeing is exactly what racerone describes.
I am seeing progress . . .
BUT - I've been grinding since about 11:00 AM and the entire middle cylinder hasn't been touched yet.
I spent 12 years in commercial construction; I know about elbow grease.
This is *painfully* slow.

Can I use emory paper or sand paper? At least to get it close?
If so, what grit?
Is there anything I can do (short of a machine shop) to speed this process?
 
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racerone

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

If you can find 120 or 180 paper it will speed it up.-Then finish it off with grinding compound.--What grade grinding compound are you using.
 
Faztbullet

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Take em to southeast cylinder head and let em throw em on there belt surfacer, 30 seconds and yer done...
1438 W Anderson St
Orlando, FL
(407) 730-9777
 
M

MAtkins

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Re: '84 Merc 150 - V6 2.0 - Rebuild - Compatible heads?

Hmm, a dilemma :eek:)

I may call Southeast Cylinder Head on Monday.
That looks like the easy way to handle it.

I think I've got some 180 grit sandpaper so over the weekend I'll play with that.
Either way it's gotta be better than the last 5 hours :eek:)

Thanks
 
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