Oil flush nightmare!

[TECH]

Hey guys, I'd like to get some input from those that have actually done oil/crankcase flushes on engines, using a "flush" of some sort, atf, etc.

I put about a quart of atf in a late model BMW to try and clean it out a little, and get a lifter to loosen up and quit knocking.
Well, it turns out that this engine wasn't taken care of, and has a lot of sludge inside. The atf cleans so well, that it loosened up a bunch of the sludge, and stopped up the oil pickup for the pump.
So, I pulled the pan off, and sure enough, it's a mess.

My question is, is flushing the engine actually something that is good for it? My take on it is that if it's got gunk in it to begin with, flushing either doesn't remove it well, or it removes it TOO well, and can cause more problems than it's worth.
I know that ATF cleans mucho well........
Normally, if the engine is clean, then a little atf helps with the lifters sticking, or not pumping up.
Now I know to be carefull about doing that...

Thoughts and experiences?

 

[SSDude]

You should use Auto-RX instead of an engine flush to prevent this problem. www.auto-rx.com

 

[Amkeer]

Not a good idea as you are finding out! I would opt for either RX or frequent oil changes using Chevron Supreme, RX probably being your best choice. You want to dissolve the deposits rather than then coming off in globs. The globs will clog passages and create problems.

Daily Drives:
-2003 Toyota Tacoma PreRunner XtraCab, Impulse Red, Peppy 2.7 Liter 4 Banger, Running Mobil1 Synthetics SS 5W-30.
ODO 7100 Miles.
-1995 Toyota 4-Runner, Evergreen, 3.0 V6, Running Mobil1 Synthetic SS 10W-30.
ODO 83110 Miles. (Switching to GC next)Nope sticking with M1.
http://community.webshots.com/user/amkeer

 

[SteveD2]

Yeah, in a normal engine a flush every other oil change or so can be a good thing, but for one as dirty is that it is a bad thing, as you now know.

 

[Chris]

Neutra 131 is another option. Slow cleaning at the start and more aggressive later.

 

[JohnBrowning]

ATF is not a flush and will not dislodge sludge! ATF is simple hydralic fluid with an anemic additive package compared to oil! It has a low flash point as well. So if some sludge broke lose it was not due to ATF!

The old ATF flush is an old wives tale with no merit at all!

If a vechile has seen decent manitence an ocasional solvent flush like every 25,000 miles is not going to hurt anything! If on the other hand it has been neglected then any solvent flush is a role of the dice at best. The only safe flush solution is Auto-Rx because it liquifys the sludge very slowly! I am not real keen on people useing a solvent flush every oil change! I just do not understand why that would be needed if the engine is seeing good maintence! I look at it kind of like an enema! If everything is working right you do not get up every morning and give yourself an enema do you?

 

[SteveD2]

quote:

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Originally posted by JohnBrowning:
ATF is not a flush and will not dislodge sludge! ATF is simple hydralic fluid with an anemic additive package compared to oil! It has a low flash point as well. So if some sludge broke lose it was not due to ATF!

The old ATF flush is an old wives tale with no merit at all!

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People here say that, but there is post after post like this one saying that it does indeed work. If the ATF didn't do anything how did his engine get clogged up?

 

[RB Shannon]

I know alot of people who swear by ATF flushes,but it really doesn't contain much in the way of detergents,it doesn't have to as it isn't designed for combustion by products.
Modern ATF's (virgin oil analysis)

But I have wondered about this,it could be that it thins the oil enough to increase it's velocity thereby mixing up more contaminants, if that were the case it might be better to add some 5w 20 as it would have an additive package more suited for use in a combustion engine.

 

[TECH]

JB, the reason I put the atf in the BMW engine (customers, not mine) was to try and get the lifters to pump up/stop sticking. I suspected poor maintenance with this car.
It's a 6 cylinder engine, holds 7 quarts of oil, and I added 1 quart of atf. I let it idle for about half an hour while I did an injector flush, and then drove it about 1 mile around the block. When I got back, the oil light came on-no oil pressure.
I removed the oil filter insert (not a spin-on filter), and it was clogged with large chunks of hard carbon or whatever deposits. I replaced the oil filter, and still no pressure.
I blew air down into the oil pump trying to dislodge the pickup screen, and got pressure back, then it clogged up again. I drained the oil and refilled a few times, but had to pull the oil pan down anyway.
What I found was a LOT of crap that had been broken loose from throughout the engine down in the oil pan.
I'd have to say that the atf is what broke that stuff loose.
I usually use a small amount of atf to get lifters to behave, but on this uncared for engine, it caused a problem.