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Engine Sludge Removal

I’m taking a upper engine class. The project for this class is to find and repair a cylinder head from a vehicle that has been damaged due to Oveheating.

I was going to reinstall the cylinder head and noticed the scale within the cooling jackets of the block. I wanted to get a second opinion on weather or not I should try and remove the scale from the cooling jackets.

If it dried coolant and light rust that is normal. If it is from oil that entered the cooling system, “sludge” as you described it the cooling system will have to be cleaned, oil in the cooling system will cause the hoses to swell. There is no point trying to clean the block alone, the radiator, heater core and hoses will have a film inside.

Of course, us Hondaphiles immediately knew it’s an open block cast from aluminum with iron inserts.

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The OP is taking a class, shouldn’t this conversation be with the instructor ?

You are correct Volvo_V70. However when you Email your professor and he doesn’t reply, then you go to the place where all your questions will be answered lil buddy, The Cartalk Community!

Nevada 545 and Stony, I went back an re-read the original post. When I read interior walls on the engine block, I thought you were talking about the cylinder walls. Other people did also which is why you got suggestions to hone the cylinder after removing the ridge.

You also did not mention you were a student taking a class. I thought you were just someone who for whatever reason took the head off the car and thought you needed some help to get it back together.

Communication is the most difficult human art.

I guess most people expected the question to be about the cylinder walls and read it that way, water jackets are not usually of interest.

From the third post;
I removed the Cylinder Head for a project in my engine class.

Yes Communication can be most difficult sometimes

I sincerely apologize for my use of foul language and a foul acronym :cry:

Once again, I’ve proven I should be in the corner, where bad boys belong :disappointed:

Is it possible the cylinder head pictured ALSO overheated?

There is usually a spec which lists the minimum cylinder head height after machining

Are you still within specs?

Not your little buddy.

Yes, The Replacement Cylinder Head That I Purchased for the Customer Also Needed to Be Resurfaced. If You Notice, In One of the pictures I posted, you can see an area shaded in blue (the area is In the center of the Cylinder Head Deck, between the cylinders.) The area shaded in blue represents where the cylinder head did not meet the required specs. It bowed right down the center of the cylinder head deck.

I did see those shaded blue areas

That is why I suspected that particular head also needed to be shaved, because of overheating

Did you check the height of the head after it got shaved?

Talk to your instructor on what needs to be done before you reinstall the cylinder head. The problem of the crusty cooling system, that’s not something I’d worry about until the head is back on. After that job is complete you can consider a cooling system flush if you like. But if the engine didn’t overheat, I wouldn’t attempt that either.

Other than agreeing with others that the corrosion or scale in the water jacket is not a cause for alarm, I will reiterate that from the pic of the cylinder bore that one cylinder that is visible does appear to be badly glazed.
This can be caused by severe overheating and can lead to an engine becoming an oil burner once reassembled.

My questions are… Is the owner of this vehicle prepared to accept an engine which smokes and/or consumes motor oil and will there be any repercussions if it does?

“The engine overheated and as a result, suffered a blown head gasket . . .”

But it DID overheat, according to OP

Yes He is. I won’t get into specifics but let’s just say my budget for getting parts for this cylinder head has been a mission in itself trying to get this project completed successfully. I basically had to tell the guy once the motor is reassembled, all warranties are null and void. I’m just glad it’s not going to effect my grade in my class because I’d really be up shit creek without a paddle. Even though I could’ve just said F*#% it, and just slap the cylinder head back in due to the Null and Void clause, I personally had never seen build up like that inside of the cooling jackets within the engine block and wanted to get a second opinion on it just incase I ever happen to run into it again. Personally If the vehicle were mine, I would have just swap the entire engine out or just junk out the entire vehicle because what you have to pay for in parts you could have just purchased another engine and have less headaches in the long run.

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holy cow, that would of been a very big ridge. bigger than any i’ve even seen.

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I am quite certain that this is NOT @VOLVO_V70.

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