Ecoboost Carbon on Intake Valves

[abs99]

Okay folks, some time back I had promised that I would use my boroscope to check for carbon build up on the intake valves of the EB engine in my Flex. The weather is finally warm enough and I've just today taken some nice photos and they are posted in my gallery http://www.fordflex.net/photos/u1446-abs.html. What you can see in the photos are images of the boroscope I used, and the sensor I removed in the top of the intake to gain access to the engine. You can see the two intake valves from the front center cylinder. I'm sorry the photos are so dark but the boroscope has limited lighting given its small size. Nevertheless, it looks to me like the top surface of one valve is worse than the other, showing some signs of carbon build up along the edge of the intake manifold itself. both show signs of carbon build up on the valve stems. Given the angle of the camera, I was not able to get a good photo of the top of the valve stem where it slides into the guide, but I would surmise that if I could see it that it would be in worse shape. You can also see a photo of my hand with a couple of spots of the black goop that came off the boroscope camera after I removed it from the engine. The goop was very thick but was definitely not a solid. I took soap and some scraping with my fingernails to get the stuff off my hand.

For reference the car has just over 30k on it now. It was run exclusively on Motorcraft semi-syn for the first 10k miles with frequent early oil change intervals (500 miles, 1500 miles, 3000 miles) and then 5k oil changes thereafter. Since then, the car has had oil changes with only Pennzoil Ultra, Pennzoil Platinum or Castrol Edge Titanium full synthetics always in 5w-20 and with the OEM Motorcraft FL500s filters. Also, the intake is completely stock and has been run for 15k miles on the OEM Motorcraft filter then with a Fram filter and now has a new Motorcraft filter in it.

Also, at 20k miles, I had run 2 cans of Amsoil Powerfoam through the intake. I have no idea what impact this had although I'm guessing it may have helped some as there was a lot of smoke coming out the exhaust and openings in the intake while I was using it. Also, I just finished running Chevron Techron in two back to back tanks of fuel on my last fill-ups prior to taking these photos. I have no idea if this had any impact on the valves but tend to doubt it.

It does look to me as though Ford has modified the variable intake timing to enable the valves to get hit with some exhaust gases at certain points in the cycle to help burn off any carbon build up on the tops of the valves but that this is not enough to keep the valve stems clean.

 

[EcoBrick Bob]

Nice Job!

Darreli had his engine cleaned with BG system. Looks like this is going to be necessary for our engines at some point. Curious how mine look after using W/M spray. But... since it doesn't spray unless I'm running 8 PSI or more, likely of limited help. Guess I need a scope....

 

[abs99]

Nice Job!

Darreli had his engine cleaned with BG system. Looks like this is going to be necessary for our engines at some point. Curious how mine look after using W/M spray. But... since it doesn't spray unless I'm running 8 PSI or more, likely of limited help. Guess I need a scope....

I got mine off Amazon for about $150 if I recall correctly. The scope is smallest size which is 9mm and the model # is GB8803, called "Explorer Premium". It works okay and having the ability to both video and photo what the camera sees on the wireless rechargeable display is really nice. The only downside is that it would be better with even brighter/more lights on the end of the camera. I bet the larger camera has better lighting but would most likely be too large for our purposes.

I would better the W/M spray is keeping your valves nice and clean. I've been thinking about doing something similar but more of a passive design to get some Marvel Mystery oil into the intake when there is vacuum in the intake (boost off). I think this could also help with fuel economy by not only cleaning up the valves but also lubricating the valve stems better. By passive I mean it wouldn't use a pump of any type. Also, it might be possible to mix in other additives, like low doses of fuel injector cleaner into the MMO to help with breaking down the carbon deposits.

In the short term, I'm going to try the Amsoil Power Foam again and take another look-see to determine if it helps at all. If it does a sufficiently good job, then maybe I won't go the Marvel route.

Oh, one other thought. I'm not so sure how the BG system would work since the spray is fine and won't "cling" to the valve stems the way the Amsoil stuff is supposed to. Also if you take a close look at the BG FuelTest site, it can clearly be seen that they were manually scraping and scrubbing the carbon off those valves. I'd rather avoid having to do that altogether if at all possible.

 

[Crash712us]

This is why I plan to clean yearly with 3m's fuel system cleaner.

 

[Showgun]

This is why I plan to clean yearly with 3m's fuel system cleaner.

Give us a headsup on that system would you Crash...
Cheers

 

[Crash712us]

i posted on here before. there is a youtube vid in this thread below.Or are you get at me being the guinea pig for. If so you have to wait a few more thousand miles probably will do every 15k. Autozone caries for less then $50.
http://www.shoforum.com/showthread.php?t=117124

 

[Showgun]

i posted on here before. there is a youtube vid in this thread below.Or are you get at me being the guinea pig for. If so you have to wait a few more thousand miles probably will do every 15k. Autozone caries for less then $50.
http://www.shoforum.com/showthread.php?t=117124

Thanks Crash. Having reviewed it, I now remember it.
Product looks good. I take it that you found out that it's compatible with our DI system?

C.

 

[Crash712us]

Can't say that Positively. But the mechanic's that I've spoken with don't see why it wouldn't be.

 

[markathome]

Interesting read. We'll definitely find out more now that this engine is used in the F150's.

 

[EB_SHO]

Looks pretty clean to me. I'd be more worried about the stuff you're dumping in the intake to try and clean it than I would be about the small amount of buildup on the valve stem.

The valve stem seals are designed to let a very small amount of oil to drip down and lubricate the guide. I think you're just seeing some of that oil build up on the stem. That won't affect the airflow at all.

30K? Drive it another 100k and look again.

 

[93rev2sev]

Looks pretty clean to me. I'd be more worried about the stuff you're dumping in the intake to try and clean it than I would be about the small amount of buildup on the valve stem.

The valve stem seals are designed to let a very small amount of oil to drip down and lubricate the guide. I think you're just seeing some of that oil build up on the stem. That won't affect the airflow at all.

30K? Drive it another 100k and look again.

Small amount? Which pics were you looking at? I've seen cleaner 300,000 mile engines

 

[abs99]

Looks pretty clean to me. I'd be more worried about the stuff you're dumping in the intake to try and clean it than I would be about the small amount of buildup on the valve stem.

The valve stem seals are designed to let a very small amount of oil to drip down and lubricate the guide. I think you're just seeing some of that oil build up on the stem. That won't affect the airflow at all.

30K? Drive it another 100k and look again.

Having seen photos of badly carboned up intake valves on Audi and VW engines, I would agree that relatively speaking these are not as bad for the miles. By the way, if you have not seen any of those photos, Google for them and you will have a better frame of reference as to what you are seeing in the photos I posted (which are admittedly poorly lit but the best I could do).

There should not be any build up whatsoever and it is very difficult to know how the build that is already there both on the stem and in the manifold around the valves may be affecting the intake air flow. For instance, I am very certain that Ford engineers took special measures to control the nature of the air flow into the combustion chamber to help improve fuel economy with the DI setup. My recollection is that there is a pocket of higher gasoline concentration near the center of the chamber and less fuel in the mix near the cylinder walls. This helps to improve fuel economy and reduce pre-ignition/detonation at the same time. What impact the carbon build up has on that configuration and I do not know but bet it isn't good.

Also, keep in mind that if there is already carbon there and it has built up some, that it will just keep getting progressively worse, perhaps at an exponential rate.

Last point, the build up of carbon can not be good for the valve guides. If the carbon gets really hard, it may, over time, begin damaging the guides, forcing them open and then further exacerbating the issue by letting more oil flow down the valve stem through the guide. Not to mention, I also fear that the carbon on the stem could cause the valves to "stick" in the guides a little and negatively affect valve timing and place undue stress on the camshafts and lifters.

Bottom line, there is NOTHING good about having significant build-up of carbon the valves, even if it were just on the valve stems.

 

[shobote]

I'd install a catch can to minimize the buildup as much as possible. oh, About the oil changes; it's considered best to stick with just one oil for the life of the vehicle to minimize buildup rather than changing to different brands, as they all have different chemical composition which react differently with the engine's metallurgy.

 

[yamahaSHO]

There is no reason you can't change oil types. Change regularly and you'll stay clear of buildup due to oil.

 

[EcoBrick Bob]

I'd install a catch can to minimize the buildup as much as possible.

The engine already has a reservoir that both traps breather oil, and allows it to return to the engine via the rear valve cover. I suppose you could add another catch can prior to this, but not sure if it would help much. I have catch cans on both my G8's and collect a considerable amount of oil.

While there may be oil & carbon deposits on the intake valves, my intake was very clean, showing no oil residue, at around 16K. G8 intakes feel greasy early on due to blow by.

 

[yamahaSHO]

I have catch cans on both my G8's and collect a considerable amount of oil.

Oil? Or brown watery stuff? A considerable amount of OIL would cause concern for me. That's how we know when we broke a piston/ring land.

 

[abs99]

The engine already has a reservoir that both traps breather oil, and allows it to return to the engine via the rear valve cover. I suppose you could add another catch can prior to this, but not sure if it would help much. I have catch cans on both my G8's and collect a considerable amount of oil.

While there may be oil & carbon deposits on the intake valves, my intake was very clean, showing no oil residue, at around 16K. G8 intakes feel greasy early on due to blow by.

EcoBrick Bob: You are correct on this. The one place where we do not have a catch can is on the pre-turbo ventilation line on the front of the engine. Turbo engines usually have two lines, one that provides positive vacuum under boost and one that provides positive crankcase vacuum when off boost. So, there is an opportunity to add a catch can to the second line . . .

 

[abs99]

There is no reason you can't change oil types. Change regularly and you'll stay clear of buildup due to oil.

Agreed, no reason not to change oil types. However, frequent changes will not prevent the build up on these valves and, some argue, makes it worse since all engine oil will have some volatile components which will find their way into the PCV system and to the valves. Longer oil change intervals it is argued will reduce the total quantity of volatile material flowing through the PCV system and slow the build up. I've been changing more frequently than recommended by Ford with a 5k OCI.

 

[yamahaSHO]

I vent to atmosphere and use water/meth injection. Next time I have the intake off, I'll look at the tops of the valves.

For my STi, I have a Crawford AOS, but will not drain it back into the engine.

 

[EcoBrick Bob]

abs99 - Think this would be a good idea, based on the amount of oil I get in my 2 G8's catch-cans. I e-mailed James @ Billett Specialties, who is one of the G8 Catch Can suppliers, but he never responded.

If you could send a pix of where the most appropriate location for placement would be, perhaps one of us can come up with something.