Get ready to shake your head at me...

[bottobot]

...so hard you might break your neck. Be warned. This post is one of the most embarrassing motorcycle mistakes I've ever made.

So while waiting for my valve compressor tool to come in I decided I wanted to clean up my cylinder heads by sandblasting them. The paint was flaking off pretty bad and the whole thing looked terrible. I took them to Motomethod (a DIY shop) where they have a small blaster. Its got some nice fine sand but doesn't work very well as its powered by too small a compressor. There are some mobility issues on the hose inside as well so its hard to get good angles. No big deal they told me all this stuff beforehand, but I thought this will be good practice and I can't possibly make it look any worse.

Which was true for the outside. Not for the inside...

My taping job was woefully inadequate and now I have sand everywhere inside the cylinders. Oil passages, valve cups, just everywhere. I can't wipe it out. My solvent bucket isn't big enough for me to splash it around in there. I'm pretty leery of taking a garden hose to it. I am really not sure what do.

Please give me some advice as I really want to fix it. Thanks guys.

Here is a pic so you can laugh and/or cry.

[Toasty]

Wow . Honestly man, I would tear it down completely and do a really through cleaning up.

[bottobot]

How would you suggest cleaning it? I am taking all the valves out and cleaning the componnets individually but I am not sure how to do the rest.

[FiremanBob]

If you have sand down in the cylinder bores you want to take it completely apart before allowing a single piston to move.

[hampshirehog]

You have got sand down the cam chain tunnel as well. You have to take that engine to bits completely and clean it in a tank. And then clean it a couple of time more again. You have to get every last grain of sand out of there before you start that engine again.

[Nessism]

I got sand inside a cylinder head like that before too. You are going to have to degrease the head to within an inch of it's life so the sand has nothing to stick to, then scrub it down with small brushes to remove the sand. I used some long engine brushes, a toothbrush, Simple Green, Gunk engine degreaser, etc. Took a LONG time before I was confident the thing was properly clean. The real challenge is down inside the oil galleys. The oil feeds up though the outer stud holes, into a horizontal galley which feeds each cam bearing, and then dumps into the cam chain tunnel. Get yourself a small diameter hose nozzle and spray water inside the various passages until you understand how the oil flows. Shoot the degreaser product down into the oil galley and let it soak for a while then flush. I did this again and again. It will help if you have some small diameter brushes to clean inside the various passages you can reach.

As I type this it occurs to me that you might want to find a machine shop with an aluminum safe dip tank to degrease the head first. After a really deep degreasing you will have a much easier time assuring there is no sand down in the various passages. You will still have to scrub the head down with the toothbrushes, but at least the oil passages should be properly degreased which will make the job easier.

Good luck

[tkent02]

You have got sand down the cam chain tunnel as well. You have to take that engine to bits completely and clean it in a tank. And then clean it a couple of time more again. You have to get every last grain of sand out of there before you start that engine again.

Then change the oil filter several times right away.

[bottobot]

Thanks for the good advice guys, just a note though. There aren't any pistons in place. I did this with the heads off the bike. So there isn't much taking apart to be done other than taking the valves out. Glad to know I'm not the only one who's done this.

[hampshirehog]

It's doable if it's just the head - you had me worried for a moment there. Ed has described the process to a tee - it's painstaking work but it's the only way.

[7981GS]

Can you at least pour solvent down into the crankcase and rock the engine side to side and flush it a few times allowing it to drain over-night and repaeating?

Eric

[bottobot]

Can you at least pour solvent down into the crankcase and rock the engine side to side and flush it a few times allowing it to drain over-night and repaeating?

Eric

Sorry if I wasn't more clear but I didn't get any sand in the crankcase. Just the cylinder heads. I would just junk the engine and slit my wrists if that were the case.

[7981GS]

Just the cylinder head and cam covers got coated with sand particles?
Much better news that I thought that I read.

Eric

[1948man]

The head was away from the rest of the engine, right? So the head is the only thing corrupted??

[1_v8_merc]

I say- reassemble and see how long a GS can run on sand????

I hear that the Hondas can run with rocks in the crankcase!

[Mekanix]

Your going to need a few things If you want to do it yourself.
I've been there and this is how I did it by my self.

Spray 9
brake cleaner
Dish washer (significant other wasn't pleased with that one)
Pressure washer
Q-tip's
hot soap and water...
Air compressor.


I soaked the head in spray nine and cleaned it off with soap and water with a brush. Then stuck it in the dish washer, then to the pressure washer.

Took it out and sprayed it with brake cleaner through all the ports and oil passages. Clean every passage with Q-tips a few times and then coat one in oil and coat the valve guides so they don't rust.

I kept at it with spray 9 and q-tips for a few hours just to be sure. but its one of those things where you can't be too careful. After all that I did actually miss some and it made its way out with little damage but I could see a few pits in the cam journals.

Hope this helps.