Cleaning head gasket surfaces

[JohnMSawyer]

It should be mentioned that you don't want to use any kind of abrasive on the engine deck, even fine-grit sandpaper, if you're not also going to remove and disassemble the engine so it can be cleaned out afterwards. If abrasive dust is left in the cylinders, it can scratch their walls, and if it gets into the oil passages, it can get into bearing surfaces and scratch them too. Abrasive dust in the coolant might not be as bad, but chunks that are large enough will clog coolant passages, some of which are pretty narrow in the radiator and heater core.

[Zen-]

what about the filings getting into coolant and oil holes?

[chasedavis]

You can spray shaving cream in the passages to capture the debris and the vacuum it out

[spooln]

Thanks for showing the CORRECT way to clean up the head/block surfaces. People who use those roloc disc's are just asking to do the job twice. although I would start with such a course grit on aluminum. I usually start with 600 and work up to 1000. i dont remember ever having to go lower then 600 to start and if you do need something lower then 600 you probably need to have that part machined. I also use a little water because I like to use wet sand paper.

[darryl]

cool tip I'm cleaning up a set of small block ford heads in the garage got it nice and shiny like this video but still see some of the "black" marks same as you have on yours should i keep sanding to remove those marks? very helpful video

[nickolasedmunds]

On the cologne v6 2.8 make sure your choke works it needs a heater tube and everything working also a filter before the fuel pump and the one is ok on the carb otherwise you can plug your mechanical fuel pump.

[HookinwithJim]

A piece of glass with sandpaper taped to it does the same thing and is more level

[angelhelp]

Years ago I attempted to remove an old head gasket from a 1984 Toyota block.  After removing the head, the gasket remained on the block, and was rock hard like it was welded to the surface even after multiple attempts to soak it with head gasket remover and scrap it off.  It visibly looked like perfectly smooth brown glass.  I worked at it for days and only made any progress after testing the edge to see if it could be removed at  all with a metal scraper.  I ended up selling the vehicle as junk just to get it out of my sight.  I am now getting ready to tackle a head gasket job on my 1986 Jeep Cherokee with a 2.8 V6 and don't want to have the same issue as with the Toyota. 

After watching your video showing you using a flat sanding pad to remove the gasket.  I have several questions.

#1 When doing the block surface, doesn't the abrasive material from the sand paper get into the oil, water and cylinder openings?  What materials should you use to stuff in the holes?  It seem like even the smallest particle of grit from the sandpaper could scar the cylinder walls.  A head can be flushed out, but the block is different since it can't be turned upside down and blown out or flushed with the cam, crank and other parts still installed..

#2 I understand that a warped head will not seal well, but the machine shop will be taking care of rebuilding my head.  The block surface presents a different problem.  I observed in your video that the outer ends and edges of the cylinder head shown look cleaner.  I conclude this is because more pressure is inadvertently being applied when hand sanding because the flat sanding pad is partly off the edge of the edge head and not supported allowing more pressure to be applied to the smaller surface in contact with the pad on the ends and edges of the head.  You can somewhat correct for this while there pieces old head gasket material remain visible on the head or block, but once it is clean, how do you know you didn't take too much off the ends and edges of the block, thus leaving it with a bowed or lower surface on the outer edges and ends?

#3 You stated the grit of the sandpaper, but not what type.  Your sandpaper looks like aluminum oxide which is commonly used for wood, but shouldn't I be using a wet/dry sandpaper which would leave less dust particles from the paper and a smoother surface?  Or am I being too picky?

#4 My Jeep was donated to me buy the original owner, and had several issues with emissions and poor gas mileage when I received it.  I solved the emissions problem with a carburetor adjustment, but it is still getting only 11 mpg which is pretty bad for a 2.8 V6.  I suspected a vacuum leak,  and found something odd when looking through all the old receipts from the original owner who had this Jeep before me.  Twice the intake manifold gasket replaced under the dealership warranty program.  To me this would indicate a vacuum leak from someone not doing the job right, or something is warped.  How do I determine the if there is a problem with the intake manifold surface or block surface?  Just how straight does it need to be?  Doesn't grinding the head effect the way the intake manifold seals l to the head?

Thank you for answering my questions.  God bless.

[rocketc.]

What's the coast of replacing the heads having them shared and refinished

[kylestivers]

What about the grains of sand that will come off of the sandpaper?

[patrickwilson]

Even the 220 grit works great for cleaning the head

[chrismc]

Or have the machine shop do it. They most likely have to correct a warp anyway. Better to pay the $100-$300 for cheap insurance rather than doing it again or worse, replacing the head and/or short/long block, used, or new crate engine

[mjl]

What about 2000 grit sandpaper? I used one of those handheld toilet brushes to clean the surface of the head where the intake manifold mounts to. Now there's fine swirl marks everywhere.

[markschmitt]

You can take one of those large green scratch pads... and epoxy it to a level piece of wood... it's slow, but gentle.

[barryparsons]

Don’t use anything aluminum oxide “sandpaper” near an engine. It will destroy bearings when the dust get into the engine.

[arthurfricchione]

Your videos are absolutely great. Wish I found your channel sooner. Very helpful. thanks, Artie

[cruzanbum]

The width, length and height of my Subaru heads leads me to believe it would take quite a bit to warp them... I just replaced my head gaskets and lapped my valves after badly overheating my engine. No machine shop involved. I hope I'm ok...

[ChanceJoneshasdanceloans]

How do you remove the pegs in the head or block, so you can sand evenly over all of the head?

[darrininverarity]

Guess this guy did body work before becoming a “professional” engine builder.

[pashko]

Geo metro(suzuki g10) engine detected :)