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Carbon Buildup

14K views 20 replies 12 participants last post by  UncleVOLK 
#1 ·
I spent my day off from work opening my manifold and manually cleaning my valves. It was a great learning experience and I'm pretty happy with the results. I used GM Top Engine Cleaner to soak the valves, but the best method by far was to scrape with picks and suck with a shop vac. I also found spraying carb cleaner and vacuuming it out worked well, kind of like at the dentist when they spray off your teeth and suck out the water.

Before:





After (I admit my patience level waned, but I'm happy):





I'm happy knowing my valves are clean and that I was up to the task. If you asked me to clean your valves I'd tell you I wouldn't get out of bed for anything less than $300.

*Thanks to Staulkor for his writeup and Stasis for their manifold removal PDF*
 
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#6 ·
Thanks all! It was a bear of a project, but as long as you take your time the results can be good.

The vehicle in question had 74K on the clock. I use a BSH block off plate and am a "moderate" driver I guess. I have a 44 mile round trip commute to work.

@el semental it's possible your valves look like this, how many miles do you have and have you ever had them cleaned?
 
#8 ·
I didn't buy any new parts. Non of my injectors popped out when I took off the manifold. I maybe should have gotten a new manifold gasket, but I never made it to the parts store.

Tools are a different story. I needed a special triple square bit, bought myself a shop vac, purchased a set of double sided pics, GM Top Engine Cleaner, and three cans of carb cleaner.
 
#9 ·
WOW. Very cool. I'm curious, as far as the "scraping" goes, from your experience did the carbon come off relatively easily, or was it like abrading granite off a cliff? Can't help but wonder what this same, un-scraped engine might look like at, say, 200K miles!
 
#11 ·
Here is the scraping in action. The carbon comes off in chunks, bits, and pieces. Once you start using chemicals it turns into basically a tar-like substance.


MY theory is this would eventually get to a point where the engine chokes itself out. There are already reports of misfires due to carbon buildup.
 
#14 ·
It looks like you're in for some serious maintenance! Safety first! Get those boots repacked, replaced if you've been driving around with them like that for a while. An easy way to clean the injectors is a product called BG 44K. It goes in your gas tank, but if you're not having misfires or poor gas mileage than your injectors shouldn't be too much of a worry.
 
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