flushing engine with Kerosene

[expat]

Originally Posted By: Bruce T
When the solvent evaporates at normal operating temperatures, can you guarantee enough oil and/or additives will remain behind to prevent scuffing at every lubrication point in the engine? I can't. Also, the oil that remains will have serious viscosity loss, so it will shear easily. Gasoline is definitely a solvent.


You seem to have a Solvent Phobia! You say it will take Many, Many OCI's to totally remove all the solvent from your engine. This is simply not true.
My reference to Two cycle engines is to illustrate the extremes that and engine can operate with diluted oil.
Now, the typical additive containing a solvent would not have anywhere near that dilution effect.
True, diluted oil is not a 'Good Thing' on a long term basis, But we only add an Additive when thinks go wrong don't we.

 

[bmwtechguy]

Kerosene will not do much cleaning, based on trying to use it as a parts cleaner several times. However, I have seen some cleaning with off-road diesel or home heating fuel, which is cheaper and still has some polar compounds in it. So if I were to cheap out and use somethng else instead of a real flush or MMO, I would use off-road diesel. I still would not expect any real cleaning, except some thinning of thick, dirty oil and removal of loose debris that washes down into the oil pan and drains out with the oil. If there is too much loose debris in a dirty/sludged engine, you always risk the oil screen getting plugged up, and then you have to pull the oil pan to fix that. So proceed wisely....

 

[Shannow]

Originally Posted By: Vspec
I know awhile back I had read a discussion around here of a guy who had a beater (Sludged engine) who filled the engine completely with Kerosene, let it sit for 24 hours and then drained it.


Could've been me.

first car was a Torana with a straight 6, that was serviced 7 years before I bought it for $200.

It needed oil, and a half quart brought it from add to full, which should have required over a quart...also sounded like it needed lifters adjusted.

The rockers were operating in their own grooves in the sludge inside the rocker cover, and I got 2 litres of what looked like moly grease out of the rocker cover.

Reassembled, and put a few litres of diesel in it. Idled for a fair while, and it drained out like black gear oil.

Put in 4 litres of home brand SF 20W-40, and it burned over a litre the first week...replaced the oil next weekend, and it burned another litre plus over a week.

I thought I was up for a new engine, but on 20W-50 Valvoline XLD it didn't burn much at all.

 

[badnews]

Originally Posted By: tigershark1976
yah, read a lot about this MMO thingy but i couldnt get it here in Singapore... i can only get some engine flush chemical (eg STP engine flush). I ever bought 1 can before and i felt like cheated becos the chemical looks like kerosene & smell like kerosene.. In fact, I believe it is kerosene lol...

Can you get ATF fluid ? Then use that if you would have been inclined to use the MMO

 

[Gary Allan]

AFT is a thinning agent. Nothing more. It has no detergent package to speak of. They're required to suspend and disperse combustion byproducts.

I don't know the mathematical decay rate of residuals with an oil change. I imagine that it will vary with the engine. You surely leave some material in the engine when you change the oil. You'll eventually reduce it to some micro percentage.

It's a YMMV deal. Something like a Rx rotary ..and you've got 2 quarts sitting in a cooler. That would take probably 10 OCI's to reduce some kero flush to some sensible flagged condition.

 

[lipadj46]

Originally Posted By: badnews
Can you get ATF fluid ? Then use that if you would have been inclined to use the MMO


Why ATF? I would think that would be even less effective than flushing with thin motor oil.

 

[badnews]

ATF is full of detergents
cleans well and has a similar viscosity to MMO
Use to be a old time oil additive before there were oil additives.

 

[badnews]

Originally Posted By: Gary Allan
AFT is a thinning agent. Nothing more. It has no detergent package to speak of. They're required to suspend and disperse combustion byproducts.

I don't know the mathematical decay rate of residuals with an oil change. I imagine that it will vary with the engine. You surely leave some material in the engine when you change the oil. You'll eventually reduce it to some micro percentage.

It's a YMMV deal. Something like a Rx rotary ..and you've got 2 quarts sitting in a cooler. That would take probably 10 OCI's to reduce some kero flush to some sensible flagged condition.


One has just to google ATF and detergent/s to see that it does have them Gary

Much more than in the past as they have become more advanced as oil have. And the dispersant has a effect similar to detergent in that it cleans the sludge. Not the way I would clean my engine but some have .

 

[badnews]

•Enhanced cleaning additives help reduce varnish formation and keep the transmission running properly longer


-----------------------------
http://www.valvoline.com/products/consum...ission-fluid/37

 

[deeter16317]

I've done it...

The main thing it is used for is if someone has a blown head gasket that fills the oil with coolant. It provides a cleaning agent that will still provide lubrication at LOW RPM (in other words at an idle). It works very well. We never did it to clean sludge or varnish...

The key is that you do multiple flushes with cheap oil immediately afterwords...to dilute/flush the kerosene/diesel. As far as I know, we never had an engine fail that had this done.

YMMV

 

[Steve S]

It would be foolish to flush your engine considering your maintenance.

 

[Kiwi_ME]

Yep, I agree, it's a bad idea.

 

[expat]

+1

 

[Bruce T]

I don't understand why would anyone use a solvent based engine flush in a modern engine when non-solvent based solutions are now available. I think it's a carryover from the old days when better solutions didn't exist. It's like people who still use K&N air filters. Outdated thinking, outdated technology.

I'm not saying an engine flush can never serve a purpose (as deeter mentions), but I do have my reservations. Stop and think about it first. There is very good reason why modern manufacturers no longer recommend engine flushes.

 

[sw99]

I am a big fan of routine flushes.

I keep up on my engine maintenance to the "T." I still like to do a flush every 8-12 OCI's for preventative measure. I would like to think that I have very clean engines...

 

[expat]

Quote, Bruce T; I'm not saying an engine flush can never serve a purpose (as deeter mentions), but I do have my reservations. Stop and think about it first. There is very good reason why modern manufacturers no longer recommend engine flushes.

Manufacturers do not recommend engine flushes, and neither would I. especially in this application. But I can imagine a case such as the Guy with an older, Sludged Lexus some weeks ago, where the engine NEEDS attention and you basically have nothing to loose.
Another valid application might be the case where coolant has mixed with the motor oil, and 'Mayonnaise' has sludged the engine.
Kerosene proberbly is not the best or the safest solution, but several other brand name additives incorporating Stoddard solvent seem to have a long history of success (or at least, not doing any harm) I have not been convinced that anything else works better, or is safer.

 

[deeter16317]

Keep in mind, it is a "better than nothing" application...not something I would do if the engine was in good condition. One reason we typically used diesel fuel is that it still has some "lubrication" qualities over something like stoddard solvent.

And further, this was done by a service station I worked at in the early 90s, on cars from the 70s and 80s...nothing as technological as today's cars.

And I guess its a matter of which is worse...driving on oil contaminated with coolant (where the owner may/may not heed the advice of flushing) or flushing (in a more/less controlled environment) with diesel fuel?

And I am in no means promoting this, I just know its been done and with no known ill effect that we ever encountered. although I have wondered what it might do to the cat converter/O2 sensor??

 

[Bruce T]

expat/deeter, those are reasonable exceptions: nothing to lose or a coolant leak. For those situations, would an engine flush be the best approach? I have no idea. I would have to defer to those with more knowledge, like bmwtechguy, Shannow, JHZR2, mechtech2, demarpaint, etc. Also, whether to use diesel fuel or any risks to the catalytic converter/O2 sensor.

I do have strong opinions, but they're not inflexible. And I can respect anyone who thinks for themselves.

 

[Gary Allan]

Well, take my neighbors 1973 CJ with 4.2 six banger. It's not street legal. It's never going to get any hours on it to work any preferred method. There was no oil to the top end on it. This has solid pushrods, the oil comes up through one of the bolts on the rocker arm shaft and disperses from there. We cleaned the packed sludge out of the shaft and restored flow there, but there's still a lifter that's ticking away below. You have to pull the head to get to the lifter, and this isn't going to be any pristine setup anyway.

This is one situation where this type of action would be about the only thing you can do.

 

[Ken2]

ATF has detergents? Nah. Lubrizol is one of the world's major suppliers of additive packages to lubricant makers. Here's their list of the additives that make base oil turn into ATF:
Dispersants... Sludge & varnish control
Antioxidants... Prohibit oxidation
Antiwear... Planetary gear, bushing, thrust washer protection
Friction modifier... Modify clutch plate and band friction
Corrosion inhibitor... Prevent corrosion and rust
Seal swell agent... Prevent loss of fluid via seals
Viscosity Improver... Reduce rate of change of viscosity
Pour Point Depressant... Improve low temperature fluidity
Foam inhibitor... Foam control
Red dye... Identification
http://www.lubrizol.com/DrivelineAdditives/AutomaticTransmissionFluidAdditives/default.html
Where's the detergents???

I've cleaned lots of oily, sludged, carboned parts in kerosene, diesel fuel, and solvent. Diesel fuel does a poor job, does very little by soaking, and requires harder scrubbing. Kerosene does a better job, but with soaking mainly just softens sludge. In an engine I'd worry about the kerosene softening sludge that eventually carries away and clogs the oil pickup screen. I might consider a kerosene soak then several very short interval oil changes in a heavily sludged engine. I wouldn't waste my time using diesel fuel. If I could get it, I'd always prefer Auto-Rx.

That Yaris will do best with continued oil changes with that good oil you've been using.