hows the best way to unstick a flathead motor/ i have put trans fluid in the cyl, holes is there any thing else that might work?
is it rusty? if so remove main caps, remove as many rodcaps and pistons as possible, pry crankshaft up with a bar and remove rest of rod caps ,remove crank, use a 2ft long bar on the piston rod bosses and a bfh to pound out remaining pistons, use care to not damage rods. no amount of miracle lube in the world will unstick a rusty flathead.
I don't know what year motor you are rebuilding but I rebuilt my 1950 Plymouth 6 cyl getting all my parts from Carquest. 31acoupe
jetmek you must have had a flatty that has been in the bottom of a lake since the 60's if marvel didn't free it up.
In addition to Chrysler/Plymouth sources, many parts for CONTINENTAL INDUSTRIAL, CLARK FORKLIFT, CLARK TUG, and RED SEAL MOTORS were interchangeable, as Chrysler corp made industrial motors for them, (or was it the other way around?,, oh well). There are a lot of sources, as soon as you start networking, one will lead to another.
Big F'ing Hammer I'm watching this very close, as the 383 in my panel is stuck from sitting for 15 years.
all it takes is one little mouse with a weak bladder to look like battery acid was poured down the intake
i will let yall know how it goes. i would really like to find a 50 dodge 6cyl flathead that is in running condition for sale! anyone know of one?
PB Blaster or Kroil usually does it for me. Ive unstuck many a sorry looking flatty. If you have to destroy the pistons and dont want to ruin the block or rods then either air chisel or torch them until a SFH does the job. A BFH usually guarantees you will at least need the rod rebuilt.
I've had great luck unsticking siezed engines with a mix of CRC-556, lacquer thinner and ATF...never failed me until that day I bought a cherry-pie little 51 ford tudor with a stuck V/8 in it. No problemo..I yanked the cylinder heads off and soaked the 2 siezed cylinders with my magic mix. After a week, the level of fluid didn't dimish in the cylinders. I'd take a whack at the piston top every time I walked by the engine on the stand. After 2 months, I lit the mix on fire to introduce a little heat into the situation. Nothin... I drove to NAPA and bought a nice big can of PB blaster and soaked the bastid another month. I even rolled the engine upside-down and soaked the bottoms of the piston skirts in PB blaster........nothin. I pulled the crank out and used mister 18 inch punch and introduced it to mister 3 LB sledge hammer from underneath. I blew the tops of both pistons off and checked the siezed rings on the busted pieces. They were totally dry! That stuff didn't seep down the piston sides at all...in 3 months! The very next siezed flathead I encountered, I didn't even waste time soaking anything....knocked the piston tops off the first day.
I once unsiezed an old chevy inline 6 with an 5lb hammer and a log that fit nicely into the cylinder.
Any engine that's stuck to a point that it won't turn after pre-lubing as much as possible ought to be disassembled and at least cleaned up, or outright rebuilt, before trying to rotate it, IMHO. All you will accomplish by rotating it is grinding the cylinders and bearings, crank journals, etc into worse shape and for what? It's very unlikely the thing is going to fire up and give you 20,000 miles of use if it is stuck hard. Bite the bullet and pull it apart. A lot of these cars were parked because the block was cracked, they had no oil pressure, or had other serious problems, so you might as well get the bad news up front.
The Jalopy Journal
