Ever hear of "GM upper end cleaner" ?
 

I'm told you buy this at a GM dealer. You run your engine and warm it up...then pour the cleaner in slowly while running. Then shut the motor off for at least 20 minutes. Then start it up and all of the carbon is suppose to be expelled for the cylinders and pistons out through the exhaust. Anyone know anything about this ?

Merc sells it as well. Works good on an engine that has a lot of carbon built up so they say. Look in a spark plug hole and see if you need it.

are you trying to get rid fo the "cold start knock" in a 6.0 ltr. motor????

I've heard chevy recommend this before.

No cold start knock
 

No, I have 540 bulldogs and I've experienced fouling out plugs due to running so rich. I've changed the primary and secondary jets and I thought I would try this stuff. I'm still running rich.

hey guys just take and old spray bottle and put water in it and with the motor running spray in carb or air intake and it will I promise clean the inside to a polished clean ,its unreal everything is clean ,just add enough throttle to keep it from cutting off and spray healthy amounts in ,,windsheild cleaner with achol and soap does the best as it has distilled water ,achol ,soap and is cheap .Fromula fasttech did this on the board then pulled the heads and about fell over it was so clean :D :D :D

bobby...


WHAT?!?!?!?!?

It's called top end cleaner (part number 000001 or something like that).

Works great if done right, removes carbon from the top end and won't hurt the injectors. Once you find a line with constant vacuum the tough part is keeping the engine running long enough to suck the bottle down. Good luck with it.

Bobby's right.
It's an age-old trick that works! A fine-mist sprayer is the key. It's like steam-cleaning your carpet...kinda...well, not really...:D

It attacks carbon by cooling it rapidly, it then flakes off and disolves.

djm has it right......you can also go to NAPA and get sea-foam........Dodge also has their version of it but cant remember the name off hand.
As for runnning it through the engine on a car....best place i have found for a good vacume source is to pull the power brake assist hose and pour it through there......or if you have a PCV valve hose attachment on the intake hose thats another good place.......only remember NOT to introduce the chemical into the intake before the MAF consor!!! :eek:

A/C Delco part number for Kleens liquid bottle( it comes in spray cans too) is 992872. This is a stronger version of GM Top Cleaner.