Premature thickening of engine oil

Had anyone put a centrifigal filter on woodgas vehicle? I have one i used to clean waste oil for fuel but built a single pass bowl type instead. Ive seen the multiple comments on blavk and thick oil so will be building a stand for my PAbiodiesel spinner to mount on valvr cover. Have one on my 6.5 and it definatkey helps and keeps the oil translucent for 3k miles…still black but can see through it and still read markings on dipstick. Get a couple ozs of muck and water out of bowl every oil change. And spinners need oil prrssure …my 6.5 is worn out and never sees over 30psi…the big block vetting gasifker sees 60 plus hot at idle and 80 going down road so should spin much faster and remove more garbage


I do not disagree with anything said.

But reflect the deference’s between the big-guys and us as individuals.
The big-guys maintenances and maintenances costs in down time; materials and labor are significant factors. Used oil “Hazardous waste” also has become a significant factor. Many of these are in locals where they must register lube oil purchases versus lube oils collected audits. The assumption (mostly correct) that differences were spewed out into the air or lost into the ground, then eventually aquifers.

As an individual doing my own engines oil changes the labor is mine. I can schedule engine down times. Ha! The traveling nurse Wifies vehicle always the one giving me fits! Honey! Let me have it! Not in the dark and cold, cold rain.
Open market best price oil buying I can afford the more frequent changes. Afford the better filters. Afford selected less-wear additive supplements for each engine usage.
I have no inputs versus outputs audits I have to be slaved too.
My disposal is the allowed 3; one gallon plastic milk jugs a recycling street-side pick-up period.

SHTF, and unable to get new oils then I’d have to rethink; reclaim and re-use a lot. Ha! I once had over 300 gallons stored here of my own drain outs for working shops waste oil heaters winter heating supplementing. Where we learned that synthetics burn poorly. Residue clogging the burner heads orifices.


(Nitration becomes significant at temperarures 135°F or 57°C) this explaines why on my hot trip back from Argos why my oil started to get thick and jell up. Oil pressure started to drop a low rpms. I changed the oil and a new oil filter and the problem was gone. I had over 3000 miles on that oil when it was changed. It was also the high mileage snythic blended oil. I am now running good old regular 10-30 grade oils. The cheap Walmart oil will work it is only going to be used for 2000 miles. Thanks for more infomation on this Rendert.

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A friend of mine uses corn oil in the summer in his 1969 F-250 390cid. He’s been doing this for 30+ years, though not many miles. Has anyone else heard of something like that.

Canola oil (rapeseed oil) was originally used as a lubricant for things including firearms. I don’t know what the autoignition temperature for it is though.

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If we could filter the gas better, maybe it wouldn’t be a problem?

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And castor bean oil if the base of Castrol.

A huge problem in Diesel engines is NOX production
But they don’t turn their oil to jelly

Another thing that I was thinking too
The fuel itself is full of highly reactive co and hydrogen

Maybe that plays a roll?


Castor was for a very long time constantly seres the best lube oil because as it cooks t thickens and it’s film strength improves
It’s still used in a lot of applications like rc fuel
It also smells nice

My mentor EC Birt used to say I pricked my finger this morning and it still smells like blendsall

Used used it blended with synthetic 2 stroke in methanol
It could be reliably counted on to lubrication when things got too hot

I did use it as a top line in my 4 stroke meth motors too


Only thing I could think of is the hydrogen.

Hydrogen when combusted makes water as a byproduct, so maybe vapors are getting into the engine, not recovered, and turning to water and emulsifying. And the darkening from carbon is giving us a red herring.

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I drove old cars with diesel engines, which made the oil very dirty, even to the point of thickening, the main cause of this problem is poor sealing of the piston rings, or a worn engine. If the gases escape past the piston rings they will do damage to the lubrication system no matter what fuel you use, but if the engine seals well I don’t think there will be any problems, Mr. Wayne could say more, or JO.


Hello Tone .

I have never had any problem with the oil other than it turns black in a short time. I try to change the oil at about 4-5K miles but may start changing sooner.

For several years I have been using Castrol 10W30 bought at Walmart for about $20 for a 5 qt bottle.

I just realized the last oil that wife got me was 5W30 because they were out of the 10W30 . I just read the 5W30 bottle and it says it is a synthetic blend where as the 10 W 30 doesn’t say anything about synthetic.


Hopefully blend/semi synthetic will be good to go for a 3000 mile interval like I’m used to. Just about all High Mileage formulas are a Semi Synthetic.

We’ll see how it goes with the Sierra.


Hi Wayne if it says it is high milage synthetic blend it has more synthetic mixed into the oil , if it just says synthethic blend there is not much. They put just enough so they can say it a synthetic blend and sale it for more monies.
100% synthetic oil says it on the container I have never used it. I was using the high mileage synthetic blend. But no more for me. Back to cheaper oil for my wood burner truck.


Tone, sorry I’ve been quiet for a while, but I’ve been too busy to get involved in any discussions. Still DOWing every day and skim through all new posts eveey morning while on the porcelain chair.

I have very little knowlidge of motor oils, except reading the price tags. I always use cheapest mineral 10W30. I’ve never had an oil related engine issue and never noticed any thickening. Oil change once every summer.
Now that I have two woodgas vehicles the number of miles between oil changes automaticly shrinks to around 6,000 miles devided by two and finally no shortage of used motor oil for rust protection and chainsaws.


This topic is pretty important i think

Wayne did you ever get your oil tested to see if they could identify anything odd?

Amusing little video
Chemically there is no difference between a gas derived oil and a refined oil base
What difference there is come from performance improvements

So it should not matter to the thickening question.
And we come back full circle to the question.

Is this a chemical change in the oil caused by contamination?
Or is this a by product of tars and solids

My observation of tar effects on rings and bearing leads me to a simple guess in contamination and not chemical.

Let’s look at some failed rods
The small block is an oil starvation failure
The big block is what I’m calling a an oil thickening tar and solids

It’s an unusual looking lubrication failure


I have this test from my book, if anyone is interested.
1-9 is oil from diesel gas powered tractors with wet cleaners, 10-11 is oil from diesel gas powered tractors with fiberglass filters.
I don’t understand much of this, I only see that insoluble products (olösliga produkter) in benzol (whatever it is) are much larger in wet cleaners.


Good morning Wallace

Maybe I should, but have never had the oil tested .


The rods are from a 208 clone and a 240 Honda.
Both ran on gengas from an experimental design

The fuel gas produced was never on the mark for best engine practices….

Both showed lots of light tars getting past rings.
Nothing ever seized or stopped moving from the tars
Both engines were destroyed by lubrication failures

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Hi Wallace . . . the lubrication failures were???
Lack of oil?
Wrong oil weight?
Someone using a substitute lube like canola oil?
A slow-speeder running at low RPM’s?

Steve unruh