Anyone had a valve cleaning performed yet?

[Retired Bob]

With our GDI engines, I thought this post from a senior member on the Corvette member was worth the read as it is a good explanation. My dealer said I should have my valves cleaned about every 25k miles - that's gonna be very expensive (and require a lot of crushed walnut shells).

 

So, has anyone had their valves cleaned?

 

"I've EXCLUSIVELY used Top-Tier gasoline for over a decade, and the research on the benefits is compelling in traditional fuel-injected engines. However, the research is also beginning to show that Top-Tier doesn't prevent the emerging problems of valve deposits on gasoline, direct-injected (GDI) engines, and all the LT engines now are GDI. In fact, the majority of modern engines now are GDI.

In traditional port-fuel injection engines, the injectors spray fuel on the valves, and the detergents in Top-Tier fuels do a good job of keeping them clean. In a GDI engine, the fuel is injected directly into the cylinders, by-passing the valves, and the same cleaning effect does not take place. The industry has recognized that new oil and fuel standards are required for GDI engines, and they are under development, but, as of yet, it's not clear what the answer is.

Thus, it's questionable that Top-Tier fuel alone can produce the same benefits in our GDI engines. It's a potentially, very large, "ticking time-bomb" w/ many GDI cars showing severe valve deposits relatively early in their lifetimes. Right now, the only solution is removal of the top-end, and mechanical valve cleaning."

Last edited by Foosh; 07-10-2016 at 10:43 AM.

 

[TJay74]

I doubt anyone has as of yet. I would venture to guess that only the exhaust valves are going to show any real deposits. I would just have the GM top end cleaner or something similar ran thru every 10k miles to keep the deposits on the low side.

[njk4o5]

engine needs complete tear down, cleaning, and then rebuild every 25k. Dealer is 100% correct

[BigBadSierra]

Find another dealer that's not fishing for your cash.

[Silverado Steve]

Throw a can of Seafoam, CRC or Gumout intake valve cleaner through every 25K. Lots of discussions on catch cans and if they help. I'm not taking my truck in every 25K for a valve job; instead I run Seafoam through and at 42K haven't experienced an engine failure. To my knowledge there is no stated requirement in our warranty books and schedule of maintenance that says a valve job is required...sounds like a major upswell by your dealer...much like them trying to sell you a highly encouraged paint sealant at time of purchase.

[MikeNH]

25k is a bit excessive but you guys are over-imagining the procedure. They just pop off the intake manifold to clean the valves.

[ColoRetiree]

engine needs complete tear down, cleaning, and then rebuild every 25k. Dealer is 100% correct

 

I just checked the 2016 Silverado User Manual maintenance section, and there is no mention of this "complete tear down". It is hard to believe that GM would build and people would buy a truck that needed a complete tear down every 25k.

 

I would love to hear from anyone who has actually had a "complete tear down" at 25k.

Edited August 22, 2016 by ColoRetiree

[Retired Bob]

I don't think he REALLY meant a 'complete' tear down - it's just the underside of the intake valves that need cleaning as with a DI engine there is no gasoline being sprayed to the under side of the valves. Thus the article was that even Top Tier gas does no good in keeping the valves clean when they don't get sprayed in the first place.

[Silverado-Hareek]

This issue has been discussed exhaustively in the catch can thread. It would take a while but you should read through that.

-

-A mechanical cleaning is one way to clean the valves. The other method is to run Seafoam or do a BG Induction Service which pumps cleaning chemicals into your engine at the throttle body to clean the valves. This should be done every 15,000 miles. Nothing that goes into the gas tank will every wash over the backside of the valves so Gumout, STP, and Techron fuel system cleaners or Top Tier Gasoline will do nothing to keep your valves clean. They will, however, help other parts of your fuel system so it's not a bad idea to use these products.

 

My personal opinion, your manual doesn't say anything about it because these engines likely won't have major mechanical issues from valve buildup until 100k+ miles. At that point, cleaning the valves would be a "repair job" not a maintenance item.

Edited August 23, 2016 by txab

[njk4o5]

I do mine every 20k to be on the safe side

[cbrsilv15]

Running a higher octane fuel in these GDI will do nothing as far as cleaning the valves. 87 for me.

[Silverado-Hareek]

Running a higher octane fuel in these GDI will do nothing as far as cleaning the valves. 87 for me.

 

Correct. I run 89 based on the recommendation of Blackbear Performance with regards to engine knock. I run Shell for it's top tier status with regards to cleaning the engine. But yes either way it will do nothing for the valves themselves. Only a manual cleaning, upper induction cleaning service, or prevention with a catch can will help the valves. I prefer a combination of using the catch can to reduce the valve buildup and an upper induction cleaning service every 15,000 miles to clean off the stuff that does get by the catch can.

[Silverado Steve]

There is no reference in either warranty or maintenance guide of a valve cleaning. Like I mentioned earlier, I do a GDI valve intake cleaning at 25K and every oil change I throw a whole can of Seafoam into the crankcase when there is about 5% oil life left on the OLM which for me is about 350 miles. You can get any brand of intake valve cleaner from Wally World for $6-$8. I haven't taken the valve cover off or seen my intake valves, but I am confident and comfortable that my truck will suffer some other catastrophic failure such as a water pump or transmission, long before my engine takes a dump. Last I saw the newly redesigned 3.5 Ecoboost coming out next year will have a port injector to hose of the intake valve with gas. The new Tacoma 3.5 taken from Lexus already runs this setup.

Edited August 23, 2016 by txab
removed off topic material

[mookdoc6]

hmmm.....Gm reconfigured the intake/outlet ports on their heads to minimize the problem recently......hmmm.....go check out the Ford Ecoboost boys forums all coked up at 50,000K.....hmmmm Ferd's new 3.5 EB has completely addressed this seemingly made up problem of GDI's coking the valves to Mt Rushmore granite hardness!

 

All of which are facts and all of which can be found on the internet......interesting!

Edited August 22, 2016 by mookdoc6

[Silverado-Hareek]

http://artofgears.com/2016/02/26/all-2nd-gen-3-5l-ecoboost-v6s-for-f-150-to-benefit-from-direct-port-injection/



Back on topic, I don't think you need a mechanical cleaning every 25k miles but how much are they charging for it? I do like mechanical versus chemical just so it's not blowing all that crap through your engine and exhaust system.


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Edited August 23, 2016 by txab