Removing carbon buildup within exhaust manifold

[ChristopherASA]

There must have been a valve or ring problem ( ? ) with the engine that my "new" exhaust manifold came from. Three or four little "mountains" of carbon were sitting in one of the engine-side ports. I scrapped those off, but is there something I can run through the ports to remove such carbon build-up that might still be there but which I can't see? THANKS. /ChristopherASA

[noahwins]

Baking soda blasting works great at cleaning carbon, grease and light rust and corrosion. Harbor Freight makes a cheap gravity feed blow gun that should work well enough for spot cleaning.

[BradMph]

Let me guess, the carbon was sitting in the port that the EGR valve dumps crap in. Damn EGR valves just shoving engine poo right back down the engines throat for a reburn.

[ChristopherASA]

Noahwins and BradMph: thanks for the suggestion, Noah: there's a Harbor F in town. Brad: not sure if that's the EGR-associated port or not. I'll have to take a look tomorrow after returning home.

I learn something eeeeeevery day from the nick folk here.

[noahwins]

You can also try soaking it in oven cleaner and reaming it out with a rifle barrel cleaner (Wal Mart).

[pennyman1]

or soak it with charcoal lighter fluid and use the rifle barrel cleaner - less toxic and low fumes

[BradMph]

In that port Chris, there should be another little port hole that the egr vent dumps, you will need like the guys said above to hone it out. It comes from the egr sub valve in the carb thru the intake manifold then thru the head to the rear exhaust port hole and is just a small tube casted vent hole that gets very clogged up with carbon. You'll probably get about a half a cup of carbon crap. This is just in case you didn't know that that tube hole was there or not. It's in the number 4 port if not mistaken. Just FYI bud.

[ChristopherASA]

Pennyman1 and Noahwins:

Pardon my being gone so long; had some extended family visit from "the other coast" and spent much time with them. Hey, the "casted vent hole" to which Pannyman1 referred is on the forward-most port (Cyl 1?), and located about five inches from the oxygen sensor. The carbon goop was in the 3rd port from the front (Cyl 3). Not even sure I'm asking a question, and I obviously need to read the manuals more.