Sludge in Valves

[mluder]

I did it... I started my foray into the Valley of Death. Surpridingly no issues with bolts breaking and the valley appears to be in pretty good shape. On my way to replacing my water pump (note the coolant in the valley), clutch slave, and general cleaning and polishing the engine bay.

When I removed the manifold I found this sludge on the intake ports and valves. I don't think that's typical.

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So... what is it indicative of? What do I do to correct? Engine flush?

FYI - I did an oil change about 1500 miles ago.

Thanks for any help in advance.

Cheers,
Steve

[DMCMW Dave]

Actually looks pretty normal.

[David T]

Very normal. If you feel you have to clean it up just use some solvent on a rag and wipe it off. Just make VERY sure you do NOT drop any parts in there!!!!!!!! Use rags to keep any dirt or parts from getting in till you reinstall the intake manifold. Or masking tape. Just don't forget to remove it! Use a dab of grease in the groove to hold the "O" rings in place when you install the intake manifold. When you install the manifold you have to slide it a little and you do not want the "O" rings to move out of the grooves. Consider yourself very lucky you did not have to contend with any broken bolts. You could easily spend more time removing them then the whole rest of the job! BTW, this has nothing to do with changing the motor oil.
David Teitelbaum

[Ron]

+1

Never ever, ever put engine flush in a good engine...it softens and turns loose crud etc in the crankcase, top of the heads, and lubricating system...the last thing you want to do. Besides, it wouldn't flow through that area....

[mluder]

Thanks, everyone.

Good to know that things are normal in that area. I was concerned because periodically when I check the oil I give it a sniff test and it smells kinda burnt. I was afraid that I had a ton of build-up in there that was causing the oil to burn.

So running an engine flush is a bad idea at all times? Just curious... My engine has only 10,000 miles on it but she sat for almost 10 years before resurection so I assume there's porbably some sludge in the oil pan. Perhaps I'll drop that at some point and clean it out.

Cheers.
Steve

[WelmoedJ]

Take the car on a good long drive.
Let it reach operating temperature before you go faster.
You may want to do a stretch of some 20 Miles at speeds over 85 MpH to get her really warmed-up.

This surely will clean and remove most of the remains of the past.

Welmoed.

[David T]

Properly used, under the right circumstances I have not had any problems with engine flush for the motor oil. If I feel it is necessary, I do it just before an oil change. Flushing the cooling system can also be a good idea when necessary. It is no longer a good idea to try cleaning the top end with chemicals, they can damage the catalytic convertor. Modern fuel already contains enough junk in it to clean and keep that area clean. Once a year you can use injector cleaner if you feel you must. Regular use is the best prescription to keep a car in good shape.
David Teitelbaum

[Ron]

"Properly used" speaks for it self, of coarse. But I'm curious as to under what circumstances you feel it is right, other than something like someone dumped something weird in it etc.

In any event, almost all manufactures have had written statements stating that using it will void your warranty since way before they had all of the sensitive sensors.
Have you ever worked for Jiffy Lube?

A word for the wise- Google it and see for yourself...

[David T]

If I had say, the valve covers off and it looked sludgy, I would consider flushing. If I did an oil change and it looked lumpy as the oil came out. If I had a high mileage car and did not know it's history or what kind of oil was in there or for how long. These are some things that would make me consider it. You are correct, all h-ll could come loose, that's why I would do it right before I planned to change the oil so the flush would not be in there very long. Modern oils are high detergent, they are supposed to loosen deposits and hold them in suspension. That is one of the reasons they have to be changed, at some point they get overloaded and can no longer hold all of the junk in suspension. If you use cheap oil and don't change it often you get a build-up of deposits.
David Teitelbaum

[Ron]

Wouldn't you be concerned that deposits, of a type somewhere between those that a GOOD heated acid tank don't take off (I'm sure you've seen that before) and that which turns loose with a flush, would turn loose while running down the road miles later and run through the pump and/or stop up the filter, if not suddenly stop up the pick up strainer (depending on the size and amount that turns loose)?

I'm with you on the modern oils, so if a layer is too thin for the above to be a problem, doubling up on good oil and filter changes for a while should take care of it. Otherwise, the engine is like a time bomb and land mine rolled into one and simply a core anyway, to me. I'd just be too leery of it not knowing what was inside one even without hearing all of the horror stories warning not to disturb it and seeing what's left in one after a flush.

[DMCVegas]

Wouldn't you be concerned that deposits, of a type somewhere between those that a GOOD heated acid tank don't take off (I'm sure you've seen that before) and that which turns loose with a flush, would turn loose while running down the road miles later and run through the pump and/or stop up the filter, if not suddenly stop up the pick up strainer (depending on the size and amount that turns loose)?

I'm gonna have to agree on this. I used Berryman Chemtool on an old pickup truck I had, and some sort of sludge broke loose and caused my fuel pump to seize up while driving. I would hate to have the same thing happen to an engine. Granted a fuel filter should have a bypass to keep the lubricant flowing, but on the even worse side gunk could get stuck in any one of the ports in the engine...

What we're looking at here is carbon buildup of course, and it's coming from the Fuel Injectors. Since it's CIS is sprays all the time, so the intake ports get bathed in the stuff. It happens from a combination of not running the engine up to temperature, as well as using cheap, crap gasoline with no detergents and even the wrong Octane (too high). Start using a nice top-tier fuel like Chevron or Texaco, and then pour in a bottle of Techron every 6 months to slowly dissolve the carbon and gently burn it off. Since it's CIS and always spraying too, it should clean up easier as well.

[kings1527]

Not to hijack, but I'm doing the exact same thing right now (water pump). I figured the deposit from the intake was normal but I pulled the valve covers off to repaint them and I'm wondering how much deposit is too much? I'm on my phone right now but I'll post pics tomorrow. They weren't necessarily coated in sludge but there's a pretty decent layer underneath with a notable burnt oil smell. Normal (I hope) or not normal and indicative of a shady past? Thanks!

Alex
6575

[Ron]

That would be hard to even guess about w/o pics....post some em when you can!

[mluder]

I'm gonna have to agree on this. I used Berryman Chemtool on an old pickup truck I had, and some sort of sludge broke loose and caused my fuel pump to seize up while driving. I would hate to have the same thing happen to an engine. Granted a fuel filter should have a bypass to keep the lubricant flowing, but on the even worse side gunk could get stuck in any one of the ports in the engine...

What we're looking at here is carbon buildup of course, and it's coming from the Fuel Injectors. Since it's CIS is sprays all the time, so the intake ports get bathed in the stuff. It happens from a combination of not running the engine up to temperature, as well as using cheap, crap gasoline with no detergents and even the wrong Octane (too high). Start using a nice top-tier fuel like Chevron or Texaco, and then pour in a bottle of Techron every 6 months to slowly dissolve the carbon and gently burn it off. Since it's CIS and always spraying too, it should clean up easier as well.

This is interesting... Until recently my car was running really poorly. Turned out my injectors were bad and not sealing correctly when the throttle was at zero - i.e. they would drip excess fuel at idle. In an effor to try to clean them up a bit DMCNW suggested I run some injector cleaner throught the tanks on somewhat regular basis. Didn't really help and I was always smelling unburnt fuel. I have since replaced them and things are much better now.

BTW, I was also using high octane premium gas. I few months ago - also on advice from DMCNW I switched to regular ol' unleaded. I have always filled with Chevron fuel if I have a choice.

So you don't think I should run an engine cleaner right before my next oil change? Other than than, I'll follow your advice and continue with what I'm doing now and things should clean themselves up...

Cheers.
Steve

[mluder]

Not to hijack, but I'm doing the exact same thing right now (water pump). I figured the deposit from the intake was normal but I pulled the valve covers off to repaint them and I'm wondering how much deposit is too much? I'm on my phone right now but I'll post pics tomorrow. They weren't necessarily coated in sludge but there's a pretty decent layer underneath with a notable burnt oil smell. Normal (I hope) or not normal and indicative of a shady past? Thanks!

Alex
6575

I too noticed the burnt smell in the oil - as I may have mentioned I give it a sniff test when I check it at the dipstick. I'm going to pull my valve cover to repaint them as well so I'll let you know what I find and post some pics too.

Cheers.
Steve

[kings1527]

That would be hard to even guess about w/o pics....post some em when you can!

This is definitely one of those things where a description just won't cut it! Here we go:

11995

If I had to get all CSI on this thing, take a look at the cover on the right (which is the left side on the engine). There are some scrapes on there as if someone tried to clean it before me and then left it. After they left it, it burned pretty clean around that small area they cleaned. But the grime before that was pretty heavy. Almost as if there was an issue at some point which caused the PO to pull the covers off to take a look.

Or maybe this is normal...

Alex
6575

[stevedmc]

Would 10% ethanol fuel do any good in this case? I'm thinking a tank full of ethanol laced gas and a few hours of driving would help clean those valves. I certainly wouldn't pour any cleaning products in there. If you break a huge chunk of carbon off that could be really bad.

[DMCVegas]

This is interesting... Until recently my car was running really poorly. Turned out my injectors were bad and not sealing correctly when the throttle was at zero - i.e. they would drip excess fuel at idle. In an effor to try to clean them up a bit DMCNW suggested I run some injector cleaner throught the tanks on somewhat regular basis. Didn't really help and I was always smelling unburnt fuel. I have since replaced them and things are much better now.

BTW, I was also using high octane premium gas. I few months ago - also on advice from DMCNW I switched to regular ol' unleaded. I have always filled with Chevron fuel if I have a choice.

So you don't think I should run an engine cleaner right before my next oil change? Other than than, I'll follow your advice and continue with what I'm doing now and things should clean themselves up...

Cheers.
Steve

I would not run an engine cleaner, no. And engine cleaner goes through the oil ports of the engine itself. That isn't where you're seeing an issue at. You're seeing carbon buildup on the intake sides of the Valves and the Ports themselves. Techron in the fuel will go ahead and spray everything down to slowly wash the deposits off. Inside of your engine is OK.

High Octane Fuel is absolutely bad news for an engine that doesn't need it. Prepare for one of my long-winded posts, but it's worth it.

First, know that in order for something to catch fire you need 3 things: Fuel, Oxygen, and Heat. Obviously we have both air and fuel, but we still need need heat.

Second, know how Gasoline and Diesel engines work. Gasoline provides heat through the spark plugs, and Diesel engines create heat through their very high compression ratios. In both cases heat causes the ignition of the fuel inside and thus of course the explosion that drives the piston down and creates power. The important thing about this however is of course that we achieve as complete of a combustion as we can resulting in burning as much fuel in the chamber as possible, and also that the engine dissapates as much of the heat as possible. Once detonation occurs, most of the heat that is generated is carried out of the engine with the heated exhaust gas, and the remaining portion is absorbed through the liquid coolant that flows through the engine and is dumped out by the radiator.

Why is High Octane fuel bad? Pump Gas still has the same energy factor no matter what octane level it is. No matter what you burn, it's still gonna emit the same level of BTUs and perform the same amount of work. Your car won't go any faster, only slower. So what is Octane? Octane is Gasoline's resistance to combustion!. Higher performance engines require higher octane because of their increased combustion chamber pressures, or Compression Ratios. It allows an engine to extract more energy from the fuel that it is using, thus increases torque and horsepower. But it does this with a cost. Remember that the higher the pressure, the more heat that is generated (like how Diesel engines have combustion). So you actually have a situation where the combustion chamber can push gasoline past it's flashpoint and can cause it to catch fire before the spark plug fires (pre-detonation). As a solution you increase gasoline's resistance to combustion, meaning that it has to get even HOTTER before it catches fire. This is Octane. There are different methods that represent various numbers (think Imperial versus Metric), but the physical properties are the same. The Spark Plug Temperature always remains way hotter than gasoline needs, thus it detonates the fuel with no problems.

But what happens when you use High Octane fuels in an engine that does not require them?

Higher Octane fuels need more heat to burn of course. And one of the things that I mentioned is that in a perfectly functioning engine, your goal is to burn as much of the fuel as possible that is in the Combustion Chamber. Ideally with an engine that has it's compression matched to it's fuel grade, we'll get that fuel to heat up just below it's flash point, and then the spark takes over and pushes it over the edge. In a lower compression engine, the temps do not become nearly as hot as in a higher compression one, so the higher Octane fuel never gets as close to it's flash points as lower Octane fuel in the same situation. As a result when the Sparkplug starts the chain reaction of ignition, we have a MUCH SLOWER burn because the remainder of the fuel isn't just catching, but is having to absorb more of the heat that is released from the already burning fuel. Ideally fully burned gasoline should be completely consumed and become Carbon Monoxide. But we only have a short, finite amount of time to burn gasoline. With a slower burn time, not all of it gets burned. The Hydro-Cabron chains begin to break up, but not all of the carbon is burned. Instead the hot carbon hits the rapidly cooling sides of the combustion chambers, pistons, & valves where it sticks. When it looses it's heat, it stops burning. Thus you begin to get carbon build up.

Why are there 3 grades of Octane?
You've got low octane fuel for regular cars, and High Octane for high-performance engines. Midgrade is meant to be available for screwed over engines that have high carbon deposits. Like I said, those carbon molecules begin to stick on the valves, chamber walls, and pistons, and also that after a combustion has occurred, the engine rapidly purges the heat out through exhaust and liquid coolant. Carbon however does NOT purge itself of heat quickly. It retains heat for allot longer. As a result there is excessive heat in the combustion chambers due to the residual BTUs. You also have varying factors of physical compression being increased and Chamber Capacity (CCs) being reduced as carbon deposits remain in the combustion chambers. What does this mean? You guessed it: Pre-Detonation. So you have to overcome this buy increasing the increasing the Octane of the fuel to compensate. But since the higher temps are caused by carbon, the issue will only get worse over time to where the engine doesn't' run well at all. Especially since carbon deposits will accumulate unevenly in each chamber and throw the balance of the engine off even further.

Bottom Line: DON'T use high octane fuel unless your car actually needs it.


Would 10% ethanol fuel do any good in this case? I'm thinking a tank full of ethanol laced gas and a few hours of driving would help clean those valves. I certainly wouldn't pour any cleaning products in there. If you break a huge chunk of carbon off that could be really bad.

Ethanol can be harsh on the fuel system. I don't know about the inside of the Accumulator, but with the old Fuel Pump Boot, and the O-Rings on the Primary Pressure Regulator on the Fuel Distributor, I can tell you for a fact that those items will be the first to suffer from Ethanol. I tried burning denatured alcohol in my engine and saw the results first hand.

You would be right to be concerned about the cleaning products, but that is why so many mechanics always recommend Techron. If you've ever had an bowl or a cup containing chocolate syrup and leave it overnight and tried to clean it the next day, the easiest way is to spray it with hot water. The water will slowly melt the syrup away. Techron works the same way. Chemtool is WAY too harsh, and IMO should only be used as a dip. Techron works very slowly over time to avoid chunks breaking off. That's why they always say you've got to run at least 5 tankfulls just to notice a difference. One treatment will NOT do it.

[DMCMW Dave]

This is definitely one of those things where a description just won't cut it! Here we go:

11995

6575

It's been too hot and too long between oil changes at some time in its history.

[kings1527]

It's been too hot and too long between oil changes at some time in its history.



Thanks Dave. So what would be my best course of action from here on out? I'm following the thread and not interested in an engine flush or anything like that. I'm going to do an oil change, run a series of Techron, and pretty much that's it. Any other ideas? Thanks.

Alex