Valve Train Sludge

[TopGear]

Warning - Newbie Post Ahead!
Have just removed my valve cover gasket from the old 3FE and was surprised by what I found underneath. The rocker arms, pushrods and rocker shafts all seem to be coated with a black sludge or varnish. If I scrape at it, it flakes off, and it is almost gritty when I rub it in my fingers.
I have owned this truck for just over a month, and the PO says it was well maintained. Even went as far as saying "regular oil changes". Sure doesn't look like it to me!
I will try to "flush" it by doing frequent oil changes, but is there anything else I should do? Am now worried about the oil passages etc.
Will try to attach a picture:

 

[concretejungle]

sorry i don't have much to add other than great pic, it will help the others on this board diagnose.

By the way, welcome!

 

[Andrewsreef]

I think I have the exact same problem on my 97LX450. I was shocked to see some when I replaced the PCV valve. Why I was espacially surprised is that the oil stays nice and clean between oil changes (even after 3K) so it seems to just be in the top of the motor.

If anyone has a solution besides replacing the HG, I would love to know.

Thanks

Andrew

 

[Scamper]

...the PO says it was well maintained. Even went as far as saying "regular oil changes".

Depends upon your definition of the word "regular"

He probably meant that he used regular oil, as in "not full snythetic". But he only changed it every 60K or when the truck seized up...whichever came first. Since he used the plural of the word "change" we can assume he did at least two oil changes.

 

[concretejungle]

marvel mystery oil. That stuff is supposed to clean upper engine parts right?

 

[lurker]

Try a search here on SeaFoam, others here have had some success with it.

If it doesn't blow your engine let us know, I might try it next.

BTW nice picture, what type of camera did you use?

 

[semlin]

is there any reason why you can't use carb cleaner to get it off while the valve cover is off?

 

[cary]

You want to try a product called Auto-rx. Check out the info about it on bobistheoilguy.com. Make sure you follow their directions very carefully if you want it to work properly. It will clean up most of that junk without cloging up oil passages.

You should call the previous owner what he considered regular. It looks like about once a year with the cheapest no-name oil he could find.

Cary

 

[Beowulf]

>> If anyone has a solution besides replacing the HG, I would love to know. <<

Andrew,
Replacing the HG will have no effect on oil sludge in the engine.

-B-

 

[Andrewsreef]

I realize the gasket itself will not but while the head is off, it can be serviced at least the top of the motor that is.

What is odd about mine is if you look into the hole for the PCV valve, you see some sludge. I got some on my fingers when I reached in. However, the dipstick is always very clean even after 3k. The oil is also relitively clean when I change it. Could it be I just have the stuff up top?

Thanks

Andrew

 

[TopGear]

Andrew, mine is the same - the oil looks very clean on the dipstick, but the top end is full of sludge. It almost looks "baked" on, as if the engine over-heated. There is a new radiator, that could be a warning sign! But she runs cool now.

I must admit that I am a little skeptical of running an oil additive. Has anyone ever tried that Auto-Rx? It sounds almost too good to be true!

Mark

 

[Tools R Us]

That type of deposit is from poor maintenance, but most often seen in cool humid climates, where the truck is used for short trips and not allowed to warm up properly. As the motor cools after a run, a small amount of fresh air is sucked into the motor and the moisture condenses out of the air, like dew. When restarted that small amount of water is mixed with the oil, as the motor warms up it is boiled off, as steam it rises to the top of the motor and is sucked off and burned. That is why the crankcase vent is always at the highest spot of the crankcase. If the motor is never allowed to properly warm and is shut off just as that "steam" is sitting at the top of the motor, more fresh air is pulled in with more moisture.... The moisture mixes with acids and other contaminates causing the soup you are seeing, over time some will harden and can clog passages.

On the F motors there is only enough oil flow in the valve cover to lube the rockers and valve stems, so on high miles motors tend to get some buildup there. I have adjusted the valves many times with the motor running, as long as it is idling oil just dribbles out. Not enough flow for aggressive cleaning.

>What is odd about mine is if you look into the hole for the PCV valve, you see some sludge.<

On the later overhead cam motors there is loads of oil in the head to lube all the sliding parts, it also dose a great job of cleaning. In the valve cover is a baffle box, its job is to separate the oil from the gases that are sucked off, the hose you pulled goes to that box. I bet if you take the valve cover off that most all of the goo is in the baffle and the in side of the motor is relatively clean. The bottom plate on some of the Toyota baffles are screwed on and can be removed for cleaning.

If the motor runs well with good oil pressure and temperature readings, my recommendation in both cases is to treat it to a nice trip, maybe a weekend of wheeling. Then recheck after a couple of oil changes, you maybe pleased with how well it will clean it self!

Mark, the oil is drawn into the pump through a screen in the oil pan, if you break all of that stuff loose at once you run the risk of clogging that screen and causing a very bad day. It maybe ugly but is not causing any problems right where it is!

 

[landtank]

Here is a pick of my head when it came off at 128k. I was pretty happy with how it looked. Don't know what oil and how often it was changed prior to my owning it, but from 38k til then it has been M1 every 5k.

 

[lurker]

Here is a pick of my head when it came off at 128k. I was pretty happy with how it looked. Don't know what oil and how often it was changed prior to my owning it, but from 38k til then it has been M1 every 5k.

I’ve eaten at restaurants dirtier than that!

 

[landtoy80]

<I bet if you take the valve cover off that most all of the goo is in the baffle and the in side of the motor is relatively clean. The bottom plate on some of the Toyota baffles are screwed on and can be removed for cleaning.>

True.
My head had no sludge but had a nice coating of varnish.
My baffles didn't have screws so I cleaned it best I could. Lots of crud came out.