10 replies to this topic

[Xiao_Bin]

hey guys,

i'm wondering what is the best way to clean the cylinder head and block surface so that the head gasket will be fine when refitting the engine together.
I've removed the carbon on the combustion chamber area, but there still are some black area on the surface, although it is smooth on the touch

I cant get rid of it, tried a smooth metal brush but its too smooth, and the spontex pad (green one) take ages and loose theyr material all over the water galleries


can i attack it with sandpaper? or is it fine to have it not perfectly clean?


thanks

[Bass Man]

Use fine wet 'n dry, with parafin, about 1200 should be ok, use it on a block of wood. You could also soak the head in parafin for 24hrs.

[bpirie1000]

get some sandpaper on there.might also try sandpaper and WD-40...... the smoother the better. But make sure you don't concnetrate on one area... I have an attachment for my drill that I use to clean everything up before Installing the head.

Cleaner the better....

Enjoy.......

[Xiao_Bin]

thanks guys

sandpaper and a nice square block of wood it is then, will try tomorrow
i've used some WD40, seemed to help
the head is not smooth from the start, can see the machining marks on the surface

Edited by Xiao_Bin, 15 October 2007 - 02:18 PM.

[Jammy]

Make sure you clean oilways out thoroughly after that though!

[Xiao_Bin]

Make sure you clean oilways out thoroughly after that though!

yeah thanks, i'll remember that

[Bluemini]

Get a large piece of glass, plenty of grinding paste and a good film to watch on tv while you rub the head back and forward over the paste on the glass. Old school refacing and works a treat...

Although I have used an offcut of kitchen worktop about 60cm square and stuck fine wet and dry paper to it with spray adhesive to make a masive sanding face. smear it in oil and rub the head over it for a while...

Edited by Bluemini, 15 October 2007 - 06:36 PM.

[iDustx]

Does soaking the head in paraffin work well? I'm about to try this now

[Shawbags]

won't hurt it , when they say use sandpaper I think they mean wet and dry , sand paper for wood is too abrasive in my eyes and could scratch it .

[Shawbags]

1200 grit wet and dry as above with wd40 would work well just be patient .

[dklawson]

Thanks for using search to bring up an old topic.  It's always good to see old topics come back to the top.

 

There are many ways to clean a cylinder head.  You need to give considerations to other areas before deciding how to clean.  

 

If the cylinder head is not completely apart with valves and springs removed, I personally would not use any abrasives on the chambers, ports, or sealing surface.  Wet/dry paper, sandpaper, lapping compound... they can all be left in the nooks and crannies that will eventually get into the bores.  Abrasives are perfectly OK if the head is disassembled and you can wash it thoroughly when done.

 

The kerosene/paraffin soak will help soften the old carbon deposits.  There are other cleaners you can use.  Locate and mask any brass plugs.  If the valve guides are bronze, plug them with rubber stoppers or cork.  Then use spray oven cleaner (with caustic) on the ports and chambers.  Allow it time to soak in, then use small wire brushes to scrub off the deposits.  

 

You can lap the seating surface flat as BlueMini said in his 2007 post.  However, a machine shop can handle this task a lot quicker than you can at home armed with only  a piece of plate glass and sandpaper.