Here is a list of products I came up with for our Accord: (Not sure which one I'll try yet: The key is which one will clean it where I want crud removed and not where I don't [seals and rings]. Hopefully avoiding a too-well-cleaned-engine. The length of time I use the product might be the key too?):


SOLVENT BASED CLEANING

Gunk - Run for 5 minutes from cold is what the can says and then drain. But how well can an engine be cleaned in 5 min? So, maybe this is the better choice for my purpose?

Marvel Mystery oil - Not sure how long or how much to use for an engine cleaning purpose? The container labels mention using it as an additive to achieve various results. I think this has kerosene in it. It is an old product. This is truly the most mysterious oil because they have successfully kept its ingredients a secret for a long time.


OIL BASED CLEANING

ATF - Honda shop foreman says to add a Qt to the engine and run it for a few hundred miles and then drain it out. But what about a full oil drain first and then fill to oil level with ATF and then run at idle for a time period and then drain and refill with high mileage oil?

Synthetic Motor Oil - (Eagle Engine Flush seems to be a version of this). Bottle says there are no solvents in it, but it does say it contains petroleum something or other?

Got any ideas? Perhaps I need both

NOTE: It would help to know what these various products contain. Gunk is the most open about their formula. Marvel is the least known. But what is the ATF and Mobil 1 made up of?

 

You did'nt say how many miles on the engine...but Gunk, Seafoam, Mystery Oil etc. can cause seals to leak ! ATF is an old school treatment and probably my choice next time but don't run it very long because it will not protect bearings, pistons etc like motor oil. Don't do any flush as preventative maintenance. If you know things are really gunked up..........try it.
my $.02

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by alotawatts &raquo;</TD></TR><TR><TD CLASS="quote"> "You did'nt say how many miles on the engine."

A: Yes I did, in my signature, 160K


"... but Gunk, Seafoam, Mystery Oil etc. can cause seals to leak ! "

A: I know, I recently did a Volvo and that's what happened. So, I put in 12 oz of Bars Engine Stop Leak, and 250 miles later it is just about back to normal.


"ATF is an old school treatment and probably my choice next time but don't run it very long because it will not protect bearings, pistons etc like motor oil." </TD></TR></TABLE>

A: Do you mean draining the oil and replacing the oil with ATF, or do you mean adding a quart to the oil?

(Comment: I did this to a Volvo a the suggestion of a Volvo shop foreman and he said to fill the gas tank and run it for a few hundred miles, and then drain the dirty oil out, etc. Bearings are fine.