Head Removed ::Mercruiser Inline 6 Cylinder

MercMonster

Petty Officer 2nd Class
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Jun 3, 2007
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I removed the inline 6 cylinder head from the block just minutes ago and found no visible cracks on the head and there was just a hint of moisture around the edges of the piston in the back cylinder. No visible cracks in or around the cylinders either or the block that I can see. It looks like there was a location in the head gasket itself where water may have penetrated into the oil. No cracks or tears in the gasket itself though. Is it common for water to leak between the gasket and head and flow into the oil. I have pictures that the missus is downloading right now that I may post shortly if anyone cares for a look. I'd like to go match up and get the gaskets (head & exhaust) today. The exhaust gasket was leaking water slightly in the rear to the underside of the exhaust manifold. What else should I look for in the interim while the head is removed? The water jackets are pretty built up with rust. Is there a way to flush out some of that rust? Should that be done once the head is reassembled?
 

MercMonster

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Re: Head Removed ::Mercruiser Inline 6 Cylinder

Here's the rear cylinder:

back-cylinder.jpg



I'll post some more here....
 

MercMonster

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Re: Head Removed ::Mercruiser Inline 6 Cylinder

I don't know if this is anything or not:

leak1.jpg




Ha, was just looking at this pic on the computer and saw what looked like a crack. Went out to inspect it on the boat and sure enough, cracked manifold. Can that be repaired (welded, jb weld?) or should I look for another one?

cracked-manifold.jpg
 

MercMonster

Petty Officer 2nd Class
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Re: Head Removed ::Mercruiser Inline 6 Cylinder

Here are the cylinders from front to back:

front-cylinders.jpg


middle-cylinders.jpg


rear-cylinders.jpg


Waiting on how I should proceed....;)
 
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Windykid

Lieutenant Junior Grade
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Apr 17, 2007
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1,177
Re: Head Removed ::Mercruiser Inline 6 Cylinder

Pull the gasket off and clean head. Inspect for cracks. Have magnifuxed if uncertain. Clean block. Inspect. reasemble.
 

ziggy

Admiral
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Jun 30, 2004
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7,473
Re: Head Removed ::Mercruiser Inline 6 Cylinder

Can that be repaired (welded, jb weld?) or should I look for another one?

look for another one. + do the riser too.

got mine at perfprotech.com

when i R&Red my manifold. i took the old one and filled up the waterjacket with water. next morning all the water was in the exhust runner, none in the waterjacket......
 

jimfj

Seaman Apprentice
Joined
Apr 13, 2003
Messages
40
Re: Head Removed ::Mercruiser Inline 6 Cylinder

Hello,

I have the same engine and a little water in #2 cylinder. Marine mech said it was probably headgasket. The only clue was a low end miss and and a difference in color on the plug. The only way I knew any of this was compression test.
Did you do a compression test before removing head?

What was the motivation for taking the head off?

Thank you for the pictures this newby really apreciates them!

Jim
 

MercMonster

Petty Officer 2nd Class
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Messages
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Re: Head Removed ::Mercruiser Inline 6 Cylinder

What was the motivation for taking the head off?

The previous owner stated that the "head gasket was blown". When the engine was started briefly, I checked the oil and it had the "milkshake" look. I wanted to get this thing ready for the water and see what all was wrong anyhow.

Only I keep finding more and more wrong:eek: After I found the original hairline crack, noted in box 2 below (although hard to see in this picture), I looked inside the channels after hearing of ziggy's problem. Inside the channel in box 1 it looks like it exploded outwards from buildup of heat.

block-exhaust.jpg



So that manifold is pretty much scrap from my point of view. And as I was looking over the manifold, which was still attached to the riser and rubber connector attached to it, the rubber hose snapped in half and you could tell that the inside of that rubber connector had dry-rotted. So now I'm adding that connector to my list of parts. (what is the name of that connector, BTW) HAHA:) This is getting so horrible I can do nothing but laugh and keep treading forward. Thanks for pointing that out ziggy!;)
 

MercMonster

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Re: Head Removed ::Mercruiser Inline 6 Cylinder

After a few more purchases, my budget is going to be blown for this month. What can I coat the cylinder walls and exposed metal surfaces to keep rust from forming?
 

MercMonster

Petty Officer 2nd Class
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Jun 3, 2007
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Re: Head Removed ::Mercruiser Inline 6 Cylinder

what is the name of that connector, BTW

Looks like I can answer my own question now...

I've found its the bellows assembly. Anyone have a source for this part?
 

Coors

Captain
Joined
Dec 8, 2006
Messages
3,367
Re: Head Removed ::Mercruiser Inline 6 Cylinder

Coat the walls with grease.
 

MercMonster

Petty Officer 2nd Class
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Jun 3, 2007
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Re: Head Removed ::Mercruiser Inline 6 Cylinder

Coat the walls with grease.


I'll do that!:)

Has anyone used Stem to Stern? I found availability for the bellow assembly on their site @ $55.85 Does that sound reasonable?
 
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