Hello everyone.
I took a job today that I thought was going to be a timing chain overhaul on a 2002 24v Eurovan. It had the cam/crankshaft out of sync code and ran terrible. When I pulled the engine apart I found no damage to the timing chain, sprockets, guides, etc. Just this mass of slimy very dark brown sludge. It does not at all look like the brown flaky stuff that builds up under the valve covers on motors that are neglected, it's not that stuff. It's very slimy, slippery, buttery texture with the consistancy of very thick grease.
I've never seen anything like this before and was wondering if anyone else has. Customer states that he has done the regular maintainance and has a sticker in the window for an oil change about 3000 miles ago.
If I was to hazard a guess, it looks like there might have been a very small coolant leak at the head gasket, but not enough to color the oil and during normal engine operation the water would boil off, leaving the glycol behind and after 50,000 miles, there is this buildup. Owner was complaining of coolant use, but there is external leaks at the thermostat housing and the heater cut-off valve, so I am guessing at this point.
I have an inquiry sent to Blackstone Labs to see if they have the ability to test this stuff. If so, I am going to get it tested and try and determine what this goo is made of.
Thanks for any input you might have.

 

Coolant is the only thing I can think of.

Toyota has finally been called on an oil sludge problem that has been linked to poor crankcase ventilation........just reaching.

 

My guess would be that this is all condensation buildup. Does it have a creamy to brownish color and consistancy? Usually you'll find that an engine that is constantly run cold and shut down without a complete warm up will put condensation all over the danged engine. Have you looked in the oil gallery between the heads? Even if the oil is changed regularly, unless the block gets flushed once in a while...if ya run it cold and don't let the moisture evaporate, it eventually builds up one heck of a sludge, not only under the breather cap, but also everywhere else that the oil fumes roll around...with the exception of where the oil flows freely.

I've also torn down old engines that had black sludge built up in the covers, but also nearly everywhere else. My belief was that the person never changed the oil, but added when it needed some. Hard to say. My guestimate is still condensation build up from over a long period.

And as stated above... if the heads and valve covers aren't "breathing" properly... there ya go.

 

DOHCmarauder and Fordlover, I agree, it looks like a long process of coolant buildup.
I am hoping someone else has seen this phenom and can say what it is.
This sludge buildup is the same color as the engine oil, very thickly deposited everywhere from the oil pan to the valve cover with the thickest part being in the valve cover. 1/2 inch deep in places! Everywhere else it's glazing everything like frosting on a donut. Even the inside of the oil pan. I have the timing cover off of the side of the engine and it's easy to see inside.
This engine is ruined at 50,000 miles due to this stuff.

 

I don't know if the engine is ruined. There are several good block flushes you can try to clean the block out with. The valve covers and other things you can get at, you can just dirty up your parts cleaner, after using a scraper and un-gooing what you can get your hands on. I've seen MANY engines looking like that on the inside. Try a good block flush before trashing the whole block, unless something is obviously very plugged, affecting oil pressure or breathing. All the PCV valves and the breathing systems are probably also fairly plugged with this goo.

 

Im guessing it may be oil flow related. My sister has a toyota truck and the guage goes up and down like jornals are worn. except the truck is almost new...Poor oil flow and low pressure can cause buildups

 

Had a big reply typed out - but Opera cacked its pants...

Anywho - it is essentially 1 of 4 things.

1. Engine oil getting too hot (fit a bigger engine oil cooler when it gets fixed)
2. PCvalve not working correctly, blocked etc.
3. Poor maintenance records
4. Wrong oil - USE SYNTHETIC, and make sure its the right viscosity.

If you can fix the engine, and maintain good oil pressure, make sure you check/fix all the above.

Hope that helps!

 

I think it might be a combination or at least 3 or 4 things:

1. Defective thermostat that doesn't let the engine get to normal operating temperature.
2. Ineffective or inoperative PCV system.
3. Short trips that doesn't let the engine get to normal operating temperatures.
4. The above combined with oil changes based on miles rather than time.

 

The Toyota 3.0, 3.3 and 3.5 V6 engines have a notorious reputation for sludge issues.

Toyota originally stated the cause was that owners didn't change the oil at proper intervals.

But when Toyota stated that...they also offered (on the QT) to cover the cost of repairs the owners had incured on the vehicles after the powertrain warranty ran out.

 

Just for kicks, see what oil he was using.

When you do get it back together, I'd use a diesel oil. CI-4 or later rated. It is designed to better hold particles in suspension, and should slowly clean up anything you cant get to. The engines I've used this in were spotless.

 

Oil sludge, boy does that bring back bad memories. I used to work for a Mercedes Benz dealer, and the job I got that solidified my leaving was a "sludge" job. Customer was complaining his oil level light was on, went to do a service, which it was over due for, and found lots of sludge built up under the oil cap. Not the yellowish condensation, but oil colored sludge. Mercedes is involved in a class action lawsuit due to this issue early on with a certain series of engines. It can be caused by over heating, running too cool, PCV issues, but all to commonly it's using the wrong oil that causes it. See, when this engine series came to the US, they specified "high quaility oil" be used, and most took that as brand name dino juice, but what they meant was SYNTHETIC. They become a sludge "factory" on regular oil. Back to what I started with, I pulled the oil level sensor out of that car, and it fought me coming out, and was covered in sludge. Cust played dumb and said nobody ever worked on it but our dealer(had snow tires on we did NOT install!), and it was our fault. Well the factory rep ok'd it for warranty, and I got to remove it from the car, diassemble it down to a bare block and heads, and clean every part by HAND! It's all aluminum, so nobody could cook it clean. Took a total of 86 hors till it was running again!!!!! (this was a v-8). They then screwed me on the pay for the job, and I started counting down the days till I could quit!!

 

ok guys heres 42 years of vw shop work.

1- vw is famous for bad oil coolers, first thing i found was the trans cooler in the radiator if it has one

2- the engine oil cooler

3 - sludgeing up from useing the wrong oils.these motors most at all times have 5w40 full syntec oils only.

so as you say dark brown color. it's suldge from running cheap improper for vw motors dyno oil. all you needed to do was buy 2 cases of carb/choke cleaner and start cleaning away. first by cleaning all the sludge off the top end under the valve cover. then pull the oil pan and clean it out along with spraying and cleaning out the block area from the piston bottoms down. remove the oil pump pick up tube and clean the snot out of it also so the screen is spotless clean and open.

any one with a vw who uses the car wash/fast lube changes or changes thier own oil with poor grade oil filters and uses dyno oil from any company will find that from 20 k up will get this problem.

a big word of advise last i knew before retireing was that vw will not cover this problem under warrenty, as it's only caused by the wrong type of oil and the high heat the vw motors run at. and cause dyno oils to coke/sludge up. a full syntec most be used .also another so you know the factory fill is castrol syntec german spec 5w40.

if you don't have the head off that vr6 leave it on and start cleaning it up.

also if you don't have a lot of specail vw factory tools or the money to buy them don't try pull that head and think the valve clear the pistons. WRONG on all the new/newer vw's if not right on they hit and bend real easy

 

I'm sending a sample of this sludge to Blackstone labs. I've been working on VW/Audi exclusively for 25 years now and I have never seen anything like this.
This particular customer had been taking his car into the dealer for all the service work.

 

CHOCOLATE only happens when coolant mixes with oil.

BIG QUESTION:

From WHAT?

Something is leaking over somewhere - I'd bet on a gasket, or a crack.

CAVEAT: In some Toyota engines, there is a hidden core plug in the half-shaft galley that can fail. Often overlooked, but can do it.

 

boy would i be curseing that dealer out big time. they of any know better.


graywolf

in a vw if it's in the coolant bottle it's a head gasket, radiator cooler. engine oil cooler. if it's brown and under the valve cover and in the oil pan it from the wrong oil type.
since around 2002 vw has had a standing tsb about oil grades and listed the comapanies who have grades that passed the german tests to the vw/audi specs.

the oil gets so hot it turns into some thing that looks like bunker oil big marine and rail road diesels run on. only it can't pass though the pickup screen and filter. when that happens we saw the timing chain fault kwick found. many times we were able to clean it out of the motor. some times not.

we would check the oil pressure, remove the valve cover or covers, check the camshaft bearing. if ok we cleaned the sludge out. if not new motor time.
the public really needs to read the owners manuals better if they did at all. and get used to the fact that cheap oils and oil changes don't work in the small high reving motors in cars like from over seas. even with out turbo's these little motors make heat the dyno oil can handle. making the car companies simplie say you MOST USE a full syntec grade of oil.

for those with vw's "and maybe other brands" vw/audi simplie came out with a very big multi page tsb. on how a dealer was to check and advise the customer about the problem. 90% of what i repaired vw refused to cover the work or problem under warrenty as it was found the wrong oil and oil filter was used.another yes guys the fast lube shops use the wrong filter for a more universal fit type with out any bypass valve in them.esp. on the 1.8 4 valve turbo motor.

toyota is another company fighting suldge problems and has gone to a full syntec oil spec. as per a close buddy who is a toyo shop forman at a local to me dealer.

we all really need to open or eyes to changes going on around us. the psd gang in fte is one of the more eye open bunch i have meet as they realy watch their oils and brands to keep their prized motors running at top levels all the time. now it's the gas gangs time to step up to the plate and do the same. meaning take better care of our prized rides.

todays motors rev higher and run hotter then ever before. grades and types of oil needed has changes. in our fords the factory fill has become a semiblend oil in other brands like vw/audi it a full syntec oil with vw useing castrol. that comes in 1 litter gray bottles at my last price check of near $8.00 a bottle. which is were the cheap sakes run to the fast lubes for a $15.95 change and free car wash.

lots of good and bad here with this type of problem and some one not inside or has been inside at the factory level as i was. would find it hard to understand the problem as deeply .

another note a vw turbo can reach temps of near 2000 degs plus or minus talk about cooked oil. it's right there. the oil that returns to the pan is already past boiling points.