Engine flush... Yes or No???

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Brian Bearor

Brian Bearor

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Just purchased a 63 Valiant and was thinking of doing an engine OIL flush.

Would you recommend performing or not and why?

If yes, what brand would you recommend?

Thank you
 
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The only time I blew up a slant 6 in 40 years was 300 miles after I used that garbage. I followed the directions to a T .Threw a rod. I say no to doing a motor flush with anything but a little kerosene or diesel fuel in with the old oil at the oil change before you drop it.
 
I have had limited experience with engine flushes. As far as professionally, there was a "Bilstein " engine flush at the one dealer I worked at, and it was a chemical that was pumped through with a machine. The do it at home methods with the quart of kerosene etc. i would think there is a risk of clogging the oil pump pickup screen. If the engine is that sludged up, its time to come apart IMO. This is just my thoughts and I may be wrong.
 
What does the coolant look like?
 
Are you flushing the oil or the coolant? What is the contamination you are flushing?

if oil just change it a few times after getting it hot and it gets dirty. Biggest gain I’ve seen is removing th oil pan and cleaning it out. Lot of goo and stuff can hide down there.
 
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No, I would not use an "engine flush". If you want to try to clean your engine do an oil change using 10-30 oil with 1 quart of ATF substituted for a 1 quart of oil. That won't thin the oil like kerosene or diesel fuel.
 
Brian Bearor said:
Just purchased a 63 Valiant and was thinking of doing an engine flush.

Would you recommend performing or not and why?

If yes, what brand would you recommend?

Thank you
Click to expand...
Welcome to the site first off.
I have done a crankcase flush once in nearly 50 years of working on cars with an off the shelf product. There was absolutely no difference in the way the engine ran or sounded after, so I would not do it again. I would recommend using a good quality oil and filter, and changing it more frequently if all you are looking to do is get the oil cleaner and remove crankcase crud that has built up over the engines life. Unless there is something specific that you want to address. I have a 1976 Pontiac Ventura that has 39k original miles, has never been apart, yet the oil is so clean that it is hard to see on the dipstick. It wasn't like that when I got it 10 years ago, but I have been changing the oil twice a year, spring and fall, regardless of how few miles it sees. It had 27k miles when I bought it on 2011.
 
I agree with all the above on flush of oil system.
On the cooling side I did a flush of cooling system using a guys formula involving an acid and neutralizing after done, pretty involved. It was a high mile slant and it never ran hot after. Sorry but I don't remember the details , was like 10 yrs ago or so.
 
Oil flush will loosen carbon deposits which are hard ! IMO it's like adding sand to your oil. My buddy ruined his Dodge pickup 318 using engine flush. Just my 2 cents.
 
As said add a quart of ATF or Marvel mystery and put a 100 or 2 miles on it. Or maybe run a high detergent oil something with zinc too .
 
Unfortunately those chemical flushes can clog things and in an oil system this isn't ideal, it only takes seconds to waste bearings.
 
If you don't think the engine is ''sludged up'' very much, then I would run a quart of ATF in it with the next oil change and run it for 200 miles. (with a new filter of course)
ATF has a lot of detergents in it.
If it's sludged up badly, then the safe thing to do is to pull the valve cover and oil pan (slant 6), or the valve covers, oil pan, and intake manifold (V8s) and do a diesel fuel scrub and enima.
It's a really messy process.
Rinse and spray where you can to flush the crap out that is missed with brake clean and it'll be pretty good.
Then run the engine with fresh oil and 1 quart of ATF for 200 miles and change the oil again.
It should be good then.
It worked for me and the 360 in my Dart Sport.
It was badly sludged up, but now it's as clean as Kleenex..........
 
I would pull the engine and pull the oil pan and clean the pan and pump screen. You may as well regasket the engine. You could also pull and inspect the main and rod bearings while your in there. You have to remember these engines were around for leaded fuel which leaves a lot of sludge in the pan.
 
When I was suspicious my 170 had sludge in the bottom of the pan, I pulled it, put it on the stand, got the pan off and sure enough it had about 1/2" or more sludge in the bottom of the pan. It was blocking the oil pickup causing the oil light to stay on extended periods on cold startup. I cleaned it all out, replaced the rod and main bearings even though they were good, put a new oil pump in it and a new timing chain set in it and back in it went. I just now pulled it back out to swap in the hot 225 I put in a couple of weeks ago. That's the only way to safely get it out 100%.
 
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I think trying to clean out all the crud at once with a "flush" might give an engine a stroke.
Like a blood clot in a person that breaks free.
(Pun intended)
Just keep changing the oil.

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Wayyyyyyyyyy back in the day and during my infancy messing with motors, I once added some RISLONE ENGINE FLUSH to a 361" I was sporting in my 66" Charger.. Dunno that it hurt anything but I wouldn't do it anymore.
 
Brian Bearor said:
Just purchased a 63 Valiant and was thinking of doing an engine OIL flush.

Would you recommend performing or not and why?

If yes, what brand would you recommend?

Thank you
Click to expand...
I can verify the trans fluid with the oil change works and over a the course of
few oil changes the engine will be clean as a whistle without hurting anything
this method was told to me by an old timer many years ago now I am and
old timer (ha ha)
Joe
 
Honda engineering sent out a memo to all service departments stating that under NO circumstances should you flush engines . It said they have had catastrophic engine failures due to flushes .
 
Contrary to what you might think, there is nothing that will break up jellified THICK sludge in the bottom of the oil pan short of a putty knife. Nothing. If you think that, then you've never seen what I'm talking about. Stop giving people bad advice, because it simply will not work on really heavy sludge layered in the bottom of the oil pan. What it may possibly do is break up enough of it so that it gets sucked into the pickup and stops up what little oil supply there is. Additives are NOT made for heavy sludge in the bottom of the oil pan. The only way to remove it is to get the pan off and physically clean it out. Anything else is a complete waste of time and money.
 
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