Redline Rebuild Update: Buick 401 Nailhead isn’t lying down without a fight


The next Redline Rebuild engine is on the stand awaiting surgery, but it’s putting up a fight in the early stages of the overhaul. It’s a Buick 401 Nailhead, a grimy hulk of a V-8 that is locked solid. That is, no motion when we try to turn the crankshaft. The engine was yanked from a 1965 Buick Wildcat that lived in a field for many years, and traditional methods of disassembly proved fruitless.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2019/03/13/redline-rebuild-nailhead-update

Some years ago a fellow on Brit-iron (antique British motorcyles discussion) retrieved an irreplaceable English motorcyle englne from the bottom of a lake in Mexico, where it had rested for a few decades. He broke it loose with repeated applications of penetrating oil, tapping, and heat. After a couple of years of repeating that, it came apart perfectly. :slight_smile:


Will be interesting to see it with the heads and pan off. Diesel some times works. Likely the mouse house cylinder is the main issue.

Being able to soak from the top for awhile and then flipped over helps a lot. Just through the spark plug holes rarely worked well for me.


This is the stuff you need right here:
Aero Kroil from Kano Labs
It has freed up many a rusted fastener,also an engine that was never turned over, and any other frozen situation. It makes pb blaster and other penatrants​ look like water. They have a whole line of chemicals for the maintenance mechanic and resto guy.


A note the word “AERO” in the name does not refer to aircraft - although aircraft mechanics swear by it for lubricating pullies, etc. The “AERO” means it is the aerosol can version. For soaking an engine Kroil is also more economically (but still expensive) available in non-aerosol bulk cans. I’ve read a poorman’s substitute, running a close second in performance, is a 50-50 mix of acetone and ATF.


As above, diesel is good for freeing stuck pistons. However, my personal favourite is good old Coke (not diet…).


+1 on the Kroil. I’ve yet to find anything that works as well.


I’m sorry, but an entire video segment just on removing the torque converter and flex plate?


Try Mouse Milk, available from Aviall. Used it for years in aviation.


I’ve got to agree on the Aero-Kroil. I had a machinist in Prudhoe Bay turn me on to this stuff back in the late 80’s and it’s the one I grab for when dealing with any rusted/frozen bolts! It claims to seep into a millionth of an inch and it has freed up things that has simply amazed me and everyone else I’ve suggested using it


While I know the goal is to dismantle it on a stand, why not just roll it over on an old tire, and remove the crankshaft w/ the flexplate and torque converter still attached? I did this for a junkyard 302 35 years ago as a kid. Or at least loosen all the main and rod caps? My 302 had a seized piston.


My tractor set out for 2 years, AEROKroil for a couple of days and a big pipe wrench on the front PTO did the trick.


I have disassembled many stuck engine and never would have cut the torque converter or flex plate. I would have pulled the crank out with the torque converter attached and then remove them from the bare crank. It is difficult and long to do so (especially on a V8) but i have never had one that could not be done so.


What the hell is wrong with this guy? Sooo I’ll just trash the flex plate and hope i can find one later.
Wish you all the luck in the world.You do realize how old these parts are right?