Cylinder head carbon forrest

[joel5150]

71 C10 with a 307. Removed my valve covers and see a lot of carbon and muck built up around the valves and rods. To the point where the head bolts are all buried up past half their head height. I've done some "research" (I use the term loosely) I have found quite a few instances where it is suggested not to do a flush or treatment because a chunk of carbon could get stuck in the valve, jamming it in the open position. So my question is;

Anyone on here have any experience doing a flush, or have any other suggestions on how to clean it? How common is it to have a valve stuck after doing a flush?

She does run. Leave it till it breaks? LOL. Any way to clean it out without taking the head off the motor or did I just go full tard with that question?

[geezer#99]

That sludge is created from lack of a good pcv and long run times.
While you might get a valve stuck problem, I'd be more concerned about any of that stuff you disturb getting into the oil and on into your bearings.
I've had them like that. Best is to tear it down and totally clean it out. But then you're pulling the motor and partly rebuilding it.
I prefer to use a shop vac and slowly vacuum it up.
Some shop towels will finish the cleaning process under the valve covers.
Then you gotta look inside the lifter valley. It could be worse than under the covers.
Some people use diesel to wash it out but then you never know where all those fine products get to.
On a high mileage motor I'd clean it with the vac and just motor on.

[joel5150]

Perfect, thanks for the suggestions.

[kwmech]

Shop vac and a putty knife. Probably in the lifter valley also. The sludge accumulates from one main thing --- cold, moist and dirty. One is an engine running cold all the time. Two - from a poor flowing PCV system. Three - Older engine oils with additives. (My favorite, Penzoil with STP) Had a mustang when I was younger. Previous owner swore by that combo. I pulled the valve cover and it was like a jello mold. Few years later had a customer come into the shop with an F250. Said the engine was rattling. Pulled the drain plug on the pan--nothing. Shoved a screw driver in the hole and got this stringy, gooey type crap. Told him what I found and he needs a major oil change. He was one of those guy that believed that "oil never goes bad". I just spin a filter on it now and then. What-ever dude. I had to hang 2 drop lamps on both sides of the pan over the weekend, came in monday and saw the same thing, a jello mold in the drain pan.

[joel5150]

Thanks KW,

Yeah, I am dreading pulling off the oil pan. The stuff I scrubbed out of the valve covers was pretty sludgy. I'm expecting jello for sure. I will get my little shop vac and get as much as I can cleaned out of the heads.

[AcampoDave]

Don't dread pulling the pan. It goes a lot easier if you replace all those bolts with a stud kit. Then you can get the gasket set up on the studs, push the pan on and cinch 'er up.

[cadillac_al]

I vote to leave it alone and run it as is. Many engines looked like that in the 70's from our cheap oil at the time. In my younger days I used to clean them and gained nothing.

[68Gold/white]

IF you do something, do the #4 post deal, and/or pull the pan.

DO NOT try to put some stupid flush treatment in the oil. You get some of or all of the crap broke loose, you can ruin the engine at worst, or get the crud on the cylinder walls and make yourself a wonderful oil burner.

Pulling the pan is no easy task, unless you have experience doing this kind of thing. Worst part is the safety aspect, dealing with the heavy engine in suspension while working on it on your back, under the vehicle...I've done it, likely never again!!!

If the engine performs fairly well, and serves your purpose until you can completely rebuild it, I'd leave it alone, also!!!

[Ironangel]

I'd get as much as I could with rags and the shop vac, buy 4 cheap oil filters and a gallon of Marvels Mystery Oil along with a 5 gallon can of Delo 400 and have at her. Add 1 quart of the MMM per oil change, first two changes at 20 miles and see if the oil is cleaning up with the second change and go from there...That stuff's great on pancakes too!

[AcampoDave]

Is it really necessary to raise the engine to pull the pan on a 71?. It's not on a 63-66. In fact with the stud kit I mentioned earlier it's just simple dirty work.