Just thought I would pass this on.
I've used this product on various liquid/semi liquid and baked on oils.
Spray Nine
I've never done it, but using this might clean the "evil mung" from the intake valve area instead of the walnut thing.
I could see closing off the valves and using a soft rotary brush on a drill with the cleaner and after that vacuum/mop the liquid out of the port.
I do believe in K.I.S.S.

 

The walnut thing is used for the hard cooked on coking, not the oily goo.

 

Well let's say if your intake valves are not that far gone then.

 

Might be an idea for yearly maintenance, some people have experienced the rough scaly deposits after only a couple years.

 

This could work for some. The gunk I had was softer than I expected. I scraped and vacuumed prior to actual blasting, you would do the same prior to a chemical cleaning. Where it gets dicey is there are areas deep in there that you cannot get to with a bottle brush chucked into a drill. You could bend a bottle brush and try to get it by hand, but the blaster is more efficient.

If, like me, you have valves that are not sealing, all the chemical you spray in there(and some of the gunk) will get into the combustion chamber. This is not desirable.

You will want to open the valves near the end of the procedure to spray and brush the seats, which will put some spray and gunk in there, don't really want to add to that.

The brushing action would splatter gunky spray all over, so you'd still want to do some masking(not as much as with shell blasting).

It would be about as much work as the shell blasting procedure. You could save some money on tool purchases if you don't have access to a blaster, an air compressor and hose, as well as buying blast media.

As for yearly maintenance, I don't want to ever have to do that again! Removing the intake was a pain! I've got catch cans set up now to keep the deposits from forming. Much, much better solution. I imagine there are deposits in the intercooler also, that I will no longer be adding to. And all the crankcase contaminants that are no longer going into the turbo, intake, combustion chamber, catalytic converter.

My initial plan was to scrape and spray, but once I opened it up, I went right back to Harbor Freight and bought my blaster and media.

In summary, (this got longer than I hoped) you should do a leak down test to see if your valves are leaking(so, you do have an air compressor after all, I knew it!). If no leaks, open it up. If deposits are light, you may be able to get away with chemical cleaning. If you have leaky valves, or heavy deposits, I would advise shell blasting.

 

X2 what RJ said.