Ace12ace12

I've had a seized starter bolt for 2 months now on this spare truck I have. I tried wd-40 pb blast and liquid wrench and couldn't get the thing to buge and finally snapped the head on the bolt. So I did research on best penetrating oil. I found that mixing ATF and acetone works better then stuffed listed above. So I mixed it and for acetone used nail polish remover with acetone let it soak for five minutes and tried it and it came right out. Thought I would let you guys know so if you had a seized nut or bolt. Oh and the mix is 50/50 for acetone and auto trans fluid.

part time

I used acetone and ATF in my 1940 farmall A tractor to free up seized pistons. Mix works good. Glad to hear your bolt came out.

Scraptor

My best friend had a similar recipe, he used atf and Colman camping fuel, aka naphtha gas.
It worked great on seized engines.

Chris Salvesen

I snapped my upper starter bolt. Snapped three "super" outs on it AFTER soaking it with Aerokroil for a few days and heating with a torch. Ended up just drilling it out and bolting the starter on with a longer bolt and a nut on the backside. Luckily it was on the upper side where the bell housing actually has room for a nut. Wish I'd have read this first, but Aerokroil is supposed to be the best stuff out there, costs $15 a can and you can't buy it in the stores, and it didn't work so I figured I was screwed.

Ace12ace12

That's what I was going to do if I couldn't get it out. I used craftsman one way sockets.