The dumb**** previous owner must have assumed there was a cylinder head leak because every few months my AF gets littered with particles and turns a dark orange. I've replaced the radiator and hoses and done some low-pressure purges to try to eject the crud- at this point I could care less if I ruin the gasket that this garbage-in-a-bottle is supposed to fix. Anyone know how to better remove it without tearing down and machining the short block? If that's what it comes down to fine but I was hoping someone knew some magic or something to make it disappear.

I hate Stop Leak. Hate it. Man-up and swap the cylinder head gasket if you warp the head. Its not that hard to do.

 

No kidding... I got mine cleared with a couple runs of "Prestone radiator cleaner" the one that specifies for neglected radiators.
Works really well, I've even had it kick holes in my thermostat gasket (was only rtv)

 

1 cup cascade,run 30 minutes with cap on then flush with water. It should look like new when you look in radiator. I have done this many times for cleaning up a Dexcool mud pie.

 

just keep flushing

 

We use Mr. Clean to run through the diesel engines that have an oil cooler failure....cleans the system up well. Drain all the coolant, add one quart of Mr. Clean run the engine for an hour at operating temp and flush out system. Put in fresh coolant and your good to go, will smell like a newly mopped kitchen floor for at least a month.

 

I guess my hesitation with cascade is that it is meant to remove oil & grease, and while I've heard its wildly successful I'm not that confident it'll break down the stop leak.

I've flushed at least a dozen times and it'll run clear until I put another thousand miles on it. Then there's little flecks of StopLeak that start showing up again and it turns orange. This is with premixed 50/50 AF and the final flush with distilled water.

I pulled the trigger on an aluminum three-row and I'm going to replace all the hoses and thermostat so I'll run a cup or two of cascade through before & after. Any other solvents or substances that might break down StopLeak without eating gaskets?