[mike sevel]

I hope I have caught your attention with the tricky title of "Tornado/Kerosene" oil flush. I had a brainstorm (yes it frightened me also) for a unique and inexpensive oil flush. Although most BMW owners change their oil regularly, sludge can build up in some models. There are several commercial oil flushes sold at varying costs.
As an inexpensive and easy alternative, I am suggesting that the oil should be drained, plug replaced and add two quarts of kerosene. The kerosene is very thin and will dissolve sludge deposits. After a few hours or overnight, drain off the kerosene but leave the plug off. Then use an air gun (or a leaf blower) with a rag around the tip (to avoid oil blow back) and shoot the air in the engine oil filler hole for 5+minutes. This should blow out any remaining sludge and kerosene. Allow draining to stop, replace plug and then refill with oil.
Your opinions?
Mikey

[6ixSpd]

The issue is see is that kerosene is only going to dissolve what it directly comes in contact with, and then you'll have to likely flush it with oil once or twice after to ensure all of the kerosense is gone from circulation.

Why bother with all that trouble when a good sludge/engine cleaner additive is only $10-$20 and has no further flushing needed?

Seems like a solution to a problem that doesn't exist...

[Nickco43]

Bad idea

[ryan stewart]

Lemme tell you a story. Its a story of an E30. Its a story of an E30 that had a 73,000 mile M3 motor thrown into it. Its a story of an E30 that, after racing with that engine (aka stupid high temps and whatnot) for a few years and reaching 165,00 miles, had the engine pulled to do some upgrades.

Guess what I found. A pristine valvetrain just covered in a light coat of oil that would come off with a wipe of the finger to show shiny metal and an oil pan that could be cleaned with a paper towel.

Use the right oil and change it on schedule and "sludge" is about as real as the monster under your bed.

Nobody ever even thinks about doing this (nothing even like what you are talking about, just pouring some kerosene into the dipstick hole and soaking) unless you are talking about a high mileage car that hasnt had its oil changed in 6 years.

[mecheng77]

What he said, just do a 500km oil change unless you have evidence of serious sludge, if that’s the case use 1l of auto trans fluid before oil change and go for short drive

[Bimmer_Engineer]

1 liter is like 1 quart...most engines require 5+ quarts of oil...

I don’t think it’s a good idea to drive around with ATF in your engine at all...and certainly not with 20% or less of the rated capacity...

Just to be clear I think it’s a terrible idea to pour kerosene into your engine too...

[nsjames]

it's an old trick to pour some diesel into a motor to try and clean it up. seafoam et. al. is generally just naptha as well. Same concept.

and it's just that, OLD.

if you're running oil formulated from this century there should never be a need to flush a motor with solvents.

[mweisdorfer]

Originally Posted by mike sevel

I hope I have caught your attention with the tricky title of "Tornado/Kerosene" oil flush. I had a brainstorm (yes it frightened me also) for a unique and inexpensive oil flush. Although most BMW owners change their oil regularly, sludge can build up in some models. There are several commercial oil flushes sold at varying costs.
As an inexpensive and easy alternative, I am suggesting that the oil should be drained, plug replaced and add two quarts of kerosene. The kerosene is very thin and will dissolve sludge deposits. After a few hours or overnight, drain off the kerosene but leave the plug off. Then use an air gun (or a leaf blower) with a rag around the tip (to avoid oil blow back) and shoot the air in the engine oil filler hole for 5+minutes. This should blow out any remaining sludge and kerosene. Allow draining to stop, replace plug and then refill with oil.
Your opinions?
Mikey

Liqui Moly makes a great oil flush for about $13-14.00.

[Welcome to NBA Jam]

If you've got a car to test it on, do it and tell us what happens.

I wouldn't put kerosene in my own crankcase, especially when really cheap commercial oil flush solutions exist already. If you're already doing at least the factory schedule with an LL-01 oil, you shouldn't have any sludge.

[tlow98]

Originally Posted by Bimmer_Engineer

1 liter is like 1 quart...most engines require 5+ quarts of oil...

I don’t think it’s a good idea to drive around with ATF in your engine at all...and certainly not with 20% or less of the rated capacity...

Just to be clear I think it’s a terrible idea to pour kerosene into your engine too...

ATF commonly used by people to help lifter tick. Even GM would do this at its dealerships for certain models as a service. Not too big of a deal.

[Efthreeoh]

Let me tell you a story about an E90. An E90 with a stock N52. An E90 ordered in April 2006 and delivered to the original owner in May 2006. An E90 that now passed 350,000 miles on BMW CBS (condition based service) OCIs, some of them passing 17,500 miles . An E90 that the owner has DIY'd the valvecover gasket, oil pan gasket and OFHG and thoroughly inspected the engine for sludge and found none. An E90 still owned by the original owner these 12+ years later and who has only used BMW LL01 5W-30 and MANN HU816 oil filters.

Follow proper maintenance, and sludge is as likely as the monster under your bed.

Putting kerosene in a modern engine to de-sludge it... crazy. And the leafblower idea... WAUF'nC

[Efthreeoh]

Originally Posted by nsjames

it's an old trick to pour some diesel into a motor to try and clean it up. seafoam et. al. is generally just naptha as well. Same concept.

and it's just that, OLD.

if you're running oil formulated from this century there should never be a need to flush a motor with solvents.

If anything, a quart of Marvel's Mystery Oil run for 5 minutes.

[Efthreeoh]

OP, if you are really concerned about sludge, then next oil change, buy a automotive boroscope and fish a round the valvetrain through the oil fill hole, and the bottom-end though the drain plug hole and see what you find. If you really want, drop the oil level sensor and use a flashlight. I'd bet your engine is clean inside.

[Bamaben]

Wouldn't kerosene likely degrade your rubber valve stem seals

[e90yyc]

Originally Posted by Efthreeoh

OP, if you are really concerned about sludge, then next oil change, buy a automotive boroscope and fish a round the valvetrain through the oil fill hole, and the bottom-end though the drain plug hole and see what you find. If you really want, drop the oil level sensor and use a flashlight. I'd bet your engine is clean inside.

Good idea.

Very decent borescopes can be had for very little $ on places like Amazon or similar.

I may even pick one up just for kicks.

To the topic at hand though: my engine has close to 200,000 miles on it, and from what little I can see through the oil filler cap, is extremely clean inside. Previous owner and myself have observed BMW-recommended OCI's.