unsiezing ford flathead
Fleet Mechanic
Joined: Aug 2010
Posts: 1,994
Likes: 3
From: Morgan Hill, CA
Mix some ATF with solvent at around 50/50. Use a pump oil can to squirt a few pumps into each cylinder. The solvent could be diesel fuel, kerosene, or even something more volatile like laquer thinner (watch the fire hazard with the volatile solvents....be careful). For the AFT, don't use Ford Type F fluid because it has grit in it.....use some dex/merc fluid.
Leave the spark plugs out, and use a socket wrench with a long handle to try to gently turn the engine back and forth. It might take several applications of the fluid and several days for years of rust to break up.
That mix is cheap and easy, but messy if you pump in too much. When you finally get the engine to turn, most of the excess fluid is going to spill out of the spark plug holes, and/or go down the exhaust.
Others will chime in, but I think some of the guys will fill the crankcase with diesel to break up sludge and old motor oil.
Dan
Leave the spark plugs out, and use a socket wrench with a long handle to try to gently turn the engine back and forth. It might take several applications of the fluid and several days for years of rust to break up.
That mix is cheap and easy, but messy if you pump in too much. When you finally get the engine to turn, most of the excess fluid is going to spill out of the spark plug holes, and/or go down the exhaust.
Others will chime in, but I think some of the guys will fill the crankcase with diesel to break up sludge and old motor oil.
Dan
Fleet Mechanic
Joined: Apr 2012
Posts: 1,275
Likes: 134
You didn't give any info on the engine, what year is it, did it sit outside uncovered for 30 years, was it still in a vehicle with the hood up and no aircleaner. It could be stuck for other reasons too, drawing moisture from weather changes, the cylinders could be rusty, the valves stuck, might have thrown a rod and locked it up, it could be cracked between a valve and cyl, pull the heads and take a look.
Lead Driver
Joined: Jun 2011
Posts: 5,510
Likes: 27
From: Winnipeg, Manitoba
Mix some ATF with solvent at around 50/50. Use a pump oil can to squirt a few pumps into each cylinder. The solvent could be diesel fuel, kerosene, or even something more volatile like laquer thinner (watch the fire hazard with the volatile solvents....be careful). For the AFT, don't use Ford Type F fluid because it has grit in it.....use some dex/merc fluid.
Leave the spark plugs out, and use a socket wrench with a long handle to try to gently turn the engine back and forth. It might take several applications of the fluid and several days for years of rust to break up.
That mix is cheap and easy, but messy if you pump in too much. When you finally get the engine to turn, most of the excess fluid is going to spill out of the spark plug holes, and/or go down the exhaust.
Others will chime in, but I think some of the guys will fill the crankcase with diesel to break up sludge and old motor oil.
Dan
Leave the spark plugs out, and use a socket wrench with a long handle to try to gently turn the engine back and forth. It might take several applications of the fluid and several days for years of rust to break up.
That mix is cheap and easy, but messy if you pump in too much. When you finally get the engine to turn, most of the excess fluid is going to spill out of the spark plug holes, and/or go down the exhaust.
Others will chime in, but I think some of the guys will fill the crankcase with diesel to break up sludge and old motor oil.
Dan
oldmerc
Joined: Jul 2011
Posts: 1,538
Likes: 5
From: Edmonton,Alberta
I use a 50/50 ATF and Acetone mix for penatrating fluid but everyone seems to have a favorite . Look into the spark plug hole with a flashlight if you see rust a little exploratory may be called for .
Laughing Gas
Joined: Jun 2010
Posts: 1,035
Likes: 330
From: Waterford, VA. USA
I just recently was able to get my Flathead V8 that was stuck to free up. I just used PB blaster from your local auto parts store along with a heavy dose of patience (as suggested by one of the fine folks here). I ended up using 2 gallons over a 4 month period, filling the cylinders full, pouring in into the valley area to fill the bottom end and then continually soaking the lifters and valves each time I would walk past the old girl. When I felt it was time, I gathered my lucky rabbit's foot, my lucky hat and my lucky trusty (but rusty)
breaker bar, drained the bottom end and used up all my luck to get her to turn......easy as pie
Good luck, be patient...
w
breaker bar, drained the bottom end and used up all my luck to get her to turn......easy as pie
Good luck, be patient...
w
Elder User
Joined: Dec 2011
Posts: 701
Likes: 1
From: Echuca VIC Australia
I'm heavily into 1920s cars and have unstuck a lot of engines. I agree with the diesel/ATF mix, I put a few squirts into each cylinder 2-3 times per day for a week or so and then use a crank handle or socket and breaker bar to try and rock it free. If it feels to be taking too much force, stop and keep soaking. After it rotates, depending on engine model and access I use specially bent brass drifts to gently tap any stuck valves back down, working through the plug hole. Rotate by hand and tap down again until the valves are free. When it does start it will smoke the neighbourhood out from the ATF mix in the exhaust.
On a related note, a very old mechanic/restorer once told me that "only good engines seize". The theory was that the tolerances were still tight, a very worn engine is too sloppy to seize. I have to say, in my experience so far he has been totally correct.
On a related note, a very old mechanic/restorer once told me that "only good engines seize". The theory was that the tolerances were still tight, a very worn engine is too sloppy to seize. I have to say, in my experience so far he has been totally correct.
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Fleet Owner
Joined: Jul 2004
Posts: 27,296
Likes: 1,059
From: NM
The last flat V8 I disassembled, several valves were stuck shut (rusted in the guides). Even with the pistons free, it would hardly turn. When I got it apart completely I discovered that trying to force stuck valves to open had destroyed the top of the lifters. Forcing it could have cracked the cam. So don't ignore the valve part of the engine. 5 valves ultimately had to be plasma-torched in half to get them out of the block. Getting the guides and lifters out took an enormous amount of effort, I'm surprised the block survived it..
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oldmerc
Joined: Jul 2011
Posts: 1,538
Likes: 5
From: Edmonton,Alberta
I had 2 stuck pistons and 4 stuck valves along with all 8 exhaust guides . all it took was a whole bunch of penetrating fluid , 3 months of patience , some persuasion when patience wore thin and a couple of home made pullers for the valves and guides . Have fun with it ,think of it as a learning experience .
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