Gunk 5 min. engine flush
Thread Starter
Race Director
Joined: Jan 2006
Posts: 10,039
Likes: 0
From: CA
Gunk 5 min. engine flush
Anyone here use it? What were the results? My 86 has 100K on the clock. And last summer when I did my valve cover gaskets I noticed alot of brown waxy crap on the covers and valve train. Which I attribute to the pennzoil that the previous owner always used. Sorry pennzoil users, I have never seen a motor, and I've seen alot, that used pennzoil and wasn't full of brown sludge. Don't get me wrong, I'm the last person to advocate a "mechanic in a can". But I'm not against better living through chemistry. 
So I thought I might give the Gunk a try. Run new oil for a week or two and then drain again with new oil. I do have the fear that the sludge is the only thing holding the engine together.
So I thought I might give the Gunk a try. Run new oil for a week or two and then drain again with new oil. I do have the fear that the sludge is the only thing holding the engine together.
Melting Slicks
Joined: Jul 2008
Posts: 3,202
Likes: 0
From: Fairview, GA
I've used it on some older cars that were gummed up. It will clean it out. If the rockers or lifters have substantial wear they may start pecking, but that only happened once on a high-mileage car. Sea Foam is a good gas treatment, and Marvel Mystery Oil can be used in gas and oil. I've used Engine Restore in some that smoked a little and consumed oil.
Pro
Joined: Jan 2010
Posts: 618
Likes: 1
From: Jacksonville FL
I had that done when I got my oil changed and it works but it best to clean everything that you can get too and then add new oil. I normally use sea foam without fear of trouble later. But best thing to say is try it and see if it works.
Melting Slicks
Joined: Apr 2003
Posts: 3,110
Likes: 6
From: Red Sox Nation! RI
When I worked in parts I never let anyone touch the stuff. Too many horror stories afterwards. Gunk isn't an additive like Marvel Mystery Oil or even Seafoam, it's like kerosene. IMO I wouldn't use it in any crankcase.
Thread Starter
Race Director
Joined: Jan 2006
Posts: 10,039
Likes: 0
From: CA
Can you relate the horror stories? I've got the bottle already but not ready for an oil change yet. I understand it's not an additive, directions say you only run it for 5 minutes and then dump the oil. And at only idle, don't drive it. Like you said, I think all it is is kerosene. But kerosene is a solvent and that's what it supposed to do, desludge. I just want to see if anyone used it and had their motor spring a nasty leak, or caused any damage. I go buy the old saying "first, do no harm".
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Melting Slicks
Joined: Apr 2003
Posts: 3,110
Likes: 6
From: Red Sox Nation! RI
There were some good lawsuit type stories about people who tried to sue Solder Seal or the company I worked for, but I think they were dropped when it was determined the user never drained the Gunk from their engine
The warnings I was taught were that the 5 minute flush was not recommended for higher mileage vehicles. It could loosen sludge or residue that was making up for normal wear in internal engine parts, bearings, seals or whatever. It wasn't uncommon to hear about oil leaks or lifter ticks, etc after using it. Another note of caution was for the chance of loosening up larger pieces of sludge that could potentially clog an oil galley or oil pump strainer.
I'm sure plenty of people have used it with success but I'm not going to take that chance myself.
The warnings I was taught were that the 5 minute flush was not recommended for higher mileage vehicles. It could loosen sludge or residue that was making up for normal wear in internal engine parts, bearings, seals or whatever. It wasn't uncommon to hear about oil leaks or lifter ticks, etc after using it. Another note of caution was for the chance of loosening up larger pieces of sludge that could potentially clog an oil galley or oil pump strainer.
I'm sure plenty of people have used it with success but I'm not going to take that chance myself.
Thread Starter
Race Director
Joined: Jan 2006
Posts: 10,039
Likes: 0
From: CA
There were some good lawsuit type stories about people who tried to sue Solder Seal or the company I worked for, but I think they were dropped when it was determined the user never drained the Gunk from their engine
The warnings I was taught were that the 5 minute flush was not recommended for higher mileage vehicles. It could loosen sludge or residue that was making up for normal wear in internal engine parts, bearings, seals or whatever. It wasn't uncommon to hear about oil leaks or lifter ticks, etc after using it. Another note of caution was for the chance of loosening up larger pieces of sludge that could potentially clog an oil galley or oil pump strainer.
I'm sure plenty of people have used it with success but I'm not going to take that chance myself.
The warnings I was taught were that the 5 minute flush was not recommended for higher mileage vehicles. It could loosen sludge or residue that was making up for normal wear in internal engine parts, bearings, seals or whatever. It wasn't uncommon to hear about oil leaks or lifter ticks, etc after using it. Another note of caution was for the chance of loosening up larger pieces of sludge that could potentially clog an oil galley or oil pump strainer.
I'm sure plenty of people have used it with success but I'm not going to take that chance myself.
