Head gasket opinion

[Johnny25]

Hello BITOG,

Noob question:

I am changing the head gasket, engine head resurfaced and all.

But when mounting the head gasket I noticed a small mark in the fire ring.

Do you recommend not assembling or when everything is torqued down that dent is not going to cause problems?

Will the pressure from the head torque minimize the "dent"?

I don't recall hiting it with anything, though


Thank you!

 

[spasm3]

Did you scrape the block to remove the old gasket ?

 

[Johnny25]

Did you scrape the block to remove the old gasket ?

Thank you for replying so fast.

Of course, the head was resurfaced and cleaned with alcohol.
And the block (cast iron) scraped with blades, scotchbrite and sandpaper, and the, cleaned thoroughly with alcohol.

The image from the gasket is the cylinder head resting side.

 

[dumkid]

the gasket should crush and small imperfections on the gasket should get smoothed out. i would get another opinion though, I've never replaced a head gasket

 

[Blueshound]

I've replaced a lot of head gaskets and I can't even see what dent you are referring to. Certainly I've assembled far, far worse without problems. The gasket is thick and sturdy and will seal up all minor imperfections. Honestly I can't ever remember a failed reassembly except one time I didn't spot a cracked head. For peace of mind you can use a copper spray or other sealant.

 

[JHZR2]

I can’t really tell what we are looking at. I am not seeing a dent but it looks like there are residues on there.

Hope the scotchbrite didn’t get abrasives in places it shouldn’t…

 

[Cujet]

I don’t see a dent, I do see some surface contamination. I’d clean that off.

 

[Trav]

Thank you for replying so fast.

Of course, the head was resurfaced and cleaned with alcohol.
And the block (cast iron) scraped with blades, scotchbrite and sandpaper, and the, cleaned thoroughly with alcohol.

The image from the gasket is the cylinder head resting side.

The first thing I would do is vacuum the cylinders and all around where you used this stuff. Never use either of those near an open engine.
I don't see the damage you are referring to, clean any residue away.

 

[Johnny25]

Should be more clear now

I was referring to this specific dent, it's very smal and hardly noticeable when I pass my finger over it.

 

[Johnny25]

I've replaced a lot of head gaskets and I can't even see what dent you are referring to. Certainly I've assembled far, far worse without problems. The gasket is thick and sturdy and will seal up all minor imperfections. Honestly I can't ever remember a failed reassembly except one time I didn't spot a cracked head. For peace of mind you can use a copper spray or other sealant.

I read that the gasket should never have sealants unless the manufacturer asks for them.
But thank you

 

[Johnny25]

I can’t really tell what we are looking at. I am not seeing a dent but it looks like there are residues on there.

Hope the scotchbrite didn’t get abrasives in places it shouldn’t…

Picture above this reply

I hope so, although I covered every oil gallery to remove that possibility!

 

[Johnny25]

I don’t see a dent, I do see some surface contamination. I’d clean that off.

Will do, oddly enough, I cleaned the cylinder head and the gasket with alcohol and found the residue there... Don't know how and why!

 

[Johnny25]

The first thing I would do is vacuum the cylinders and all around where you used this stuff. Never use either of those near an open engine.
I don't see the damage you are referring to, clean any residue away.

Thank you

Everything was cleaned and blasted off with a 10bar air compressor.
Every oil galery was covered to remove the possibility of contamination with abrasives.

Tonight I'll clean it off again and start torquing to spec

 

[zzyzzx]

What type of head gasket are you planning on using?
MLS?
Something else?

 

[Astro14]

Wait, sandpaper!?

To clean an engine?

Clean this as thoroughly as you can. You’ll likely have a real oil burner when you get it running again. Tiny abrasive particles have landed in between pistons and cylinders. Maybe they vacuum out, maybe they don’t, and you’re going to have severe bore wear.

 

[skyactiv]

I'd like to see a better picture of that cylinder bore. What I see of it doesn't look promising.

 

[bdcardinal]

I'd like to see a better picture of that cylinder bore. What I see of it doesn't look promising.

Seriously. I would be more worried about the bore finish.

 

[Johnny25]

What type of head gasket are you planning on using?
MLS?
Soething else?

Composite.

Wait, sandpaper!?

To clean an engine?

Clean this as thoroughly as you can. You’ll likely have a real oil burner when you get it running again. Tiny abrasive particles have landed in between pistons and cylinders. Maybe they vacuum out, maybe they don’t, and you’re going to have severe bore wear.

Yes, water based sandpaper.

I'll describe it down, step by step:

1 - disassembly
2 - covering the cylinder holes to prevent abrasives creeping down
3 - wetting the block gasket surface with Mistolin (strong oven degreaser)
4 - scrape the most of grit with a blade (x-acto), +/- 45º angle
5 - removing the majority of the grit with scotchbrite
6 - wet sanding (600 grit) to level and remove as much of hard grit as possible; note that this wet sanding was just spraiying a bit of water to help the sandpaper glide and not drying out.
7 - cleaning the head with brake cleaner, paper and rags, followed by compressed air.

I'd like to see a better picture of that cylinder bore. What I see of it doesn't look promising.

Seriously. I would be more worried about the bore finish.

This is the 80% finished block.
You notice some darkening arround the water passages, but that surface is as flat as it can be.

The cylinder bore looks perfectly fine to me, and what you see below:

Its the reflection of oil that i brushed on the cylinder walls to help with the dry startup of the engine.

I'll post a picture with more detail as soon as I can.
But this engine didn't consume a drop of oil.

 

[mattd]

Hello BITOG,

Noob question:

I am changing the head gasket, engine head resurfaced and all.

But when mounting the head gasket I noticed a small mark in the fire ring.

View attachment 159045

Do you recommend not assembling or when everything is torqued down that dent is not going to cause problems?

Will the pressure from the head torque minimize the "dent"?

I don't recall hiting it with anything, though


Thank you!

Do you feel that with your finger or visible only?

 

[Blueshound]

Composite.



Yes, water based sandpaper.

I'll describe it down, step by step:

1 - disassembly
2 - covering the cylinder holes to prevent abrasives creeping down
3 - wetting the block gasket surface with Mistolin (strong oven degreaser)
4 - scrape the most of grit with a blade (x-acto), +/- 45º angle
5 - removing the majority of the grit with scotchbrite
6 - wet sanding (600 grit) to level and remove as much of hard grit as possible; note that this wet sanding was just spraiying a bit of water to help the sandpaper glide and not drying out.
7 - cleaning the head with brake cleaner, paper and rags, followed by compressed air.




View attachment 159080


This is the 80% finished block.
You notice some darkening arround the water passages, but that surface is as flat as it can be.

The cylinder bore looks perfectly fine to me, and what you see below:

View attachment 159084

Its the reflection of oil that i brushed on the cylinder walls to help with the dry startup of the engine.

I'll post a picture with more detail as soon as I can.
But this engine didn't consume a drop of oil.

All good. You do need to consider that there will be abrasives in the oil and coolant passages that you didn't cover. I would probably drain and fill the oil and coolant after reassembly but before you crank it. Then (after that sweet sweet sound of startup) another drain and fill of both after you run it for 10 minutes.

P.s. don't forget to pull those rags out first!!