Intake manifold off with pics of intake valves with deposits.

gone_fishing · January 21, 2015

First I have to explain why I removed the intake manifold. I've had a RX catch can installed for about 6 months now. I decided the other day I was going to try to clean up the hose installation for the catch can. I purchased some expandable braided sleeving and shrink fit tubing in an effort to make the hoses look a little more factory. While trying to remove the hose that goes from the catch can to the intake manifold I broke the plastic elbow off the comes out of the intake manifold. Needless to say I was extremely pissed that I did this as I should know better then to pull on a hose like that. After doing some research at the dealer, this elbow that comes out of the intake manifold is not a replaceable item. It's basically part of the intake manifold. I thought about trying to repair the elbow but didn't like that idea. I wanted it done right and the only way I knew how to fix it was to replace the entire manifold. Cost me about $160 shipped for a new one.

Replacing the intake manifold didn't look too bad. Of course this theory got shot down as I started to remove the cover that goes over the intake manifold. This cover really doesn't service much purpose other then to provide holes for various plastic snap-in fittings that hold an electrical harness down. These connectors are barbed so they go in easily but don't come out with out a fight. The worst ones were behind the intake that are against the firewall. Once I finally got everything out of the way I could then remove the intake manifold along with this cover.

I have about 30,000 miles on my truck when I did this. The catch can has been on for the last 9,000 miles and recently added the RX clean side separator after find oil in my intake tube (http://www.gm-trucks.com/forums/topic/168584-oil-in-intake-tubeanyone-else-check-theirs/)

I tried to take the best pics I could of the intake valves but it's tricky to get go lighting. They all appeared to have the same amount of carbon build up on them. I didn't think there would be this much on them. Assuming the catch can prevents majority of the crankcase vapors from getting back into the motor, these deposits formed within the first 20,000 miles. I would be interested to see what an engine with no catch can looks like after 100,000 miles.

Valves

gone_fishing · January 21, 2015

Pics of valves (one pic zoomed at full resolution and one pic resized)

gone_fishing · January 21, 2015

Few more valve pics

ToesonTheNose · January 21, 2015

Holy SHYT!

this is really going to decrease the life of these motors, how they hell are you gonna see 200k on this

haider320 · January 21, 2015

That looks horrible!

newdude · January 21, 2015

I tried to take the best pics I could of the intake valves but it's tricky to get go lighting. They all appeared to have the same amount of carbon build up on them. I didn't think there would be this much on them. Assuming the catch can prevents majority of the crankcase vapors from getting back into the motor, these deposits formed within the first 20,000 miles. I would be interested to see what an engine with no catch can looks like after 100,000 miles.

Honestly if it looks like that with 30k on it, and you put the can on at 9k, I bet that majority of the those deposits came in the first 9,000, and the can is doing its job. I say this because...one of our techs last week or so ripped into a 2014 with 21,600 on it (came in running bad). Had an AFM lifter collapse, wasn't opening the intake valve. The valves in the heads, looked as if they were in the truck for 150k miles. All stock, no catch can. Just relying on the factory PCV and those oil/air seperator domed sections in the valve cover (that were supposed to work 3x better than the LS PCV design).

I wish I had some better lighting but it appeared thicker on the valves and stems than on yours.

00Silverado4x4 · January 21, 2015

That is so hard to believe considering it's a brand new engine. That looks what I found on the throttle body of my 2500 with over 363k miles. That's insane!!!

07Softail · January 21, 2015

WOW....that is crazy on a basically new engine. I guess I will go ahead with the oil separator and clean side filter. Not to stray from the post but the bowl area could really be cleaned up with some port work.

RT

Bvonscott · January 21, 2015

Which RX catch can did you get? And does it affect any of the engine performance?

POS VETT · January 21, 2015

Have the intake valves media-blasted; the intake valve cleaning process in BMW direct-injected engines use walnut shell. I suppose the same media can be used in this case.

bdbake01 · January 21, 2015

Well...that's disappointing.

Silverado-Hareek · January 21, 2015

According to the gentlemen at RX, he said at roughly 11,700 miles when I installed my catch can that I probably already had a good amount of build up on my valves and may even notice a rough idle on initial start up until the engine reaches a higher temperature. Well I don't necessarily have a rough idle on initial start up but I do have a rough idle that pops up every so often regardless of engine temperature and I do attribute that to build-up on the valves. I may spring for the clean side seperator soon.

From what I've read online, those pictures don't look that bad for 30,000 miles. In fact you probably did get all of that in the first 20k miles and the catch can has prevented it from getting worse. Direct injection is not new technology to benefit the consumer, I'm of the opinion it's new technology to beneft the manufacturer's pockets. You're telling me certified engineers can't figure this problem out but us laymen are discovering it on our own? Diesel engines are direct injection and come with catch cans. The Corvette is the same engine and comes with a catch can. I think they aren't putting it on non-sports cars for 3 reasons:

1) It saves them a couple hundred bucks on manufacturing. When they sell way more of these trucks than they do Corvettes, that's a lot of profit.

2) It's a maintenance item for the consumer that soccer moms who trade in their suburbans every 3 years aren't going to want to perform.

3) For those of us that DO keep these engines for a long time, it's maintenance profit for the dealers and GM.

how they hell are you gonna see 200k on this

You aren't. Not without spending $800-$1,000 to tear down the engine and clean it.

All these guys that had Silverado's up through MY 2006 that say they never had any issues and that's why they sprung for a K2 series truck are in for a RUDE awakening.

Crf450r420 · January 22, 2015

Because most of it is at the bottom of the port, I have to wonder how much of it is reversion. I think I'm back to making a nitrous system to spray Seafoam into the intake at WOT so I can clean the intake valves when I'm having fun. Also, that port looks jacked, but maybe it is just the way it is pictured.

Higgs Boson · January 22, 2015

According to the gentlemen at RX, he said at roughly 11,700 miles when I installed my catch can that I probably already had a good amount of build up on my valves and may even notice a rough idle on initial start up until the engine reaches a higher temperature. Well I don't necessarily have a rough idle on initial start up but I do have a rough idle that pops up every so often regardless of engine temperature and I do attribute that to build-up on the valves. I may spring for the clean side seperator soon.

From what I've read online, those pictures don't look that bad for 30,000 miles. In fact you probably did get all of that in the first 20k miles and the catch can has prevented it from getting worse. Direct injection is not new technology to benefit the consumer, I'm of the opinion it's new technology to beneft the manufacturer's pockets. You're telling me certified engineers can't figure this problem out but us laymen are discovering it on our own? Diesel engines are direct injection and come with catch cans. The Corvette is the same engine and comes with a catch can. I think they aren't putting it on non-sports cars for 3 reasons:

1) It saves them a couple hundred bucks on manufacturing. When they sell way more of these trucks than they do Corvettes, that's a lot of profit.

2) It's a maintenance item for the consumer that soccer moms who trade in their suburbans every 3 years aren't going to want to perform.

3) For those of us that DO keep these engines for a long time, it's maintenance profit for the dealers and GM.

You aren't. Not without spending $800-$1,000 to tear down the engine and clean it.

All these guys that had Silverado's up through MY 2006 that say they never had any issues and that's why they sprung for a K2 series truck are in for a RUDE awakening.