john, thank you for the knowledge but no, I store my motors upright just like they sit on the boat. You’ve heard of the acid test? I forgot what that phrase means exactly but I tested muriatic acid (pool strength, 29%) as I described in an earlier post. I chose the bolt I thought would be the hardest to get out, the lower rear. I first cleaned the area with a wire bush, brake clean and compressed air. I applied the acid with a regular cotton swab just enough to soak the base of the bolt head and not drip. If it did drip I wiped the excess off with a rag. I let it sit around 10 minutes or until the bubbles stopped. Then I washed the area with brake clean and blew it dry with compressed air. The idea being I wanted full strength acid to soak in and not have it diluted with the spent acid. I repeated this 8 times, sometimes letting the acid soak longer. I was worried the acid could do damage but I see none. I will try a longer soak the next time. After all that, the bolt wouldn’t budge with a hand impact or my small Milwaukee 18V impact so I soaked it with penetrating oil for 3 days. The Milwaukee moved the bolt maybe a 32nd of a turn on day 3 but the hardened bit broke. I repaired the bit with a cut-off tool but it snapped off again after several 1 second trigger pulls. I think the small cordless impact is better than the hand impact at loosening a stuck bolt but the cordless is a lot more likely to break the bit. After a few more days soaking with oil and using the hand impact, the bolt came out whole. We’ll see how it goes with the rest of the bolts but so far it looks good for my theory of removing the aluminum oxide with the acid, then soaking with oil. Some heat would probably have sped things up in stage 2 but I didn’t have time as I was just spending a minute on my way out to work and a minute when I got back.
'48 Zephyr, restored '06, runs great
'54 Fastwin, restored '09, runs great
'57 Fastwin, unrestored, locked up in 2018
