Thread: Oil Turned to Sludge/Jelly

Originally Posted by rangieman

..............Im told its more to do with extreme operating temps , ........................... But the weekend that my oil solidified i had moved house and done some very heavy towing so the motor was worked hard ,...............................

Aah.............................I've seen oil turned to jelly only three times, twice it was to do with high temperatures. Once in 110+ degree temp driving from Perth to Heyden came accross a Toyota towing a trailer whose oil had jellified. Another time in NW WA the same thing in a Landcruiser in 110+ degree temp. The third time was with a 100,000 Km Commodore (Toyota Lexen) in for its FIRST oil change (enough to make you weep).

Did the OP have similar high temp issues ?

Deano

Seems to be a common thought of the oil being pushed beyond its limits, but from what OP describes it was pretty easy driving?

I have seen the effect of this jellied oil in farm tractors that were started as usual, but the morning was very frosty ( below -5 C ), the result was a complete rebuild of the motor.

Excessive kilometres between changes has been the another cause.

The worst culprit is a leaking fuel lift pump diaphragm, letting summer weight diesel which contains higher levels of paraffin, back into the sump, then when the cold weather occurs, this mixture will lead to oil congealment.
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Thanks everyone for your input...to answer some of the questions and add some more details:

Ambent temps have been at a max of 25C and the hardest driving on ths oil change has been sand on Teewah and Fraser - both of which weren't exactly hard and I have a lot of experience driving in sand so the engine wasn't stressed. Apart from that it's been driving 20min to work each day - so no stop/start runs either.

I guess there is a possibility the oil flush dislodged a whole lot of junk. But it seems unlikely as the previous oil was fairly clean when I dropped it after running the oil flush through, bringing the engine up the temp and then draining while hot. It is still a posibbility I guess.

I'll pull out the fuel lift pump and try and see if there's been diesel ingress with the oil. Wouldnt it dilute the oil first? I check the oil every 2-3 days and didn't notice the oil get any thinner...but how much diesel would it take to get jellying?

At the moment here's what I know...

It can't have been caused by:
Head gasket failure
Overdue oil change
Low oil level
Extreme driving or overheating

It might have been caused by:
Bad oil batch
Fuel contamination via lift pump or rings
Engine flush dislodged gunk - but as I said above it seems unlikely.

Hopefully be calling Nulon tomorrow, will keep everyone posted.

Originally Posted by wrinklearthur

I have seen the effect of this jellied oil in farm tractors that were started as usual, but the morning was very frosty ( below -5 C ), the result was a complete rebuild of the motor.

-5C won't do that alone. The last week we have been down to -11C overnight and had daily maximums of -2C. All diesels working fine (well those with winter diesel are, summer diesel filled machines are on strike).

If you really want to know what is in the sludge, get it analysed.

Just wanted to add to this as with ATF i have the same problems with shelf life of oils.

Most common problems i see with oils turning to Sludge or Rust Past is due to the age of the oil sitting on the shelf.

Oils that are not popular and sit on a shelf go off and cause these problems. A workshop i worked at had a run of vehicle returns with white sludge (Talking ATF) we noted that it could be a water issue with the transmission but we narrowed it down to an oil which was sitting in a bulk tank for more than a year. The bottom of the tank was full of this white sludge caused by condensation during transport and storage.

Oils can be tested and if you supply a sample new oil and the flush they will compare the samples. costs about $50 but worth it as its very detailed report.

Now all the comments about the oil specs not suiting the operating conditions hense causing sludge are on the money in my opinion. But this opens a door to any component that come in contact with the oil.

Any chemical that contacts the oil could cause problems. Possibilities could be some old Penrite HPR Diesel 5 does not like the Nulon High Protection Diesel Formula (similar to mixing coolants), To much EGR gas if not blocked, Fuel mixing due to rings or injectors (I know nothing about Tdi200 engines but had similar issues with Jackaroo Diesel engines) or a bad batch of oil which you need to now flush and flush.

Might be an idea to talk to the guys @ COST EFFECTIVE MAINTENANCE

Please note my knowledge base is ATF but have had similar issues with engine oil.

Cheers
Rhys

Originally Posted by RoverNova

Just wanted to add to this as with ATF i have the same problems with shelf life of oils.

Most common problems i see with oils turning to Sludge or Rust Past is due to the age of the oil sitting on the shelf.

Oils that are not popular and sit on a shelf go off and cause these problems. A workshop i worked at had a run of vehicle returns with white sludge (Talking ATF) we noted that it could be a water issue with the transmission but we narrowed it down to an oil which was sitting in a bulk tank for more than a year. The bottom of the tank was full of this white sludge caused by condensation during transport and storage.

So nothing at all to do with age, but actually caused by bad storage and moisture contamination?

Oil is already much older than your or I. It doesn't have a shelf life if properly stored.

Originally Posted by Dougal

So nothing at all to do with age, but actually caused by bad storage and moisture contamination?

Oil is already much older than your or I. It doesn't have a shelf life if properly stored.

But these days, oils ain't just oil. Maybe the modern additives don't store as well as the oil itself.