Engine Stuck! How much torque can I apply??
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Engine Stuck! How much torque can I apply??
1970, 350/350, 4spd car been sitting garaged for 20 years. Engine is stuck, pistons and cylinders are soaking with Kroil now. How much torque can I apply to the bolt at the front of the crankshaft before I either strip the crankshaft threads, strip the bolt threads, or snap the grade 8 bolt? The normal tightening torque spec for that bolt is 100 pounds as I recall. I have applied 100 pounds with my torque wrench, no movement yet.
Instructor
Joined: Jul 2009
Posts: 234
Likes: 0
From: Anchorage Ak
sounds like the rings are rusted to the cylinders, which if it wasn't fogged before storage is probably happened. I wouldnt put much more on the crank bolt, if you snap it the fun starts. Sounds like you need to pull the motor anyways and tear it down. Good Luck
Instructor
Joined: Jun 2011
Posts: 183
Likes: 1
From: Litchfield CT
stuck motor
1970, 350/350, 4spd car been sitting garaged for 20 years. Engine is stuck, pistons and cylinders are soaking with Kroil now. How much torque can I apply to the bolt at the front of the crankshaft before I either strip the crankshaft threads, strip the bolt threads, or snap the grade 8 bolt? The normal tightening torque spec for that bolt is 100 pounds as I recall. I have applied 100 pounds with my torque wrench, no movement yet.
I've been able to remove stuck pistons from the bottom by using a cut off wooden broomstick (1 1/2" diameter, couple of feet long) place it INSIDE the piston from beneath, then whack the living crap out of it with a 2 pound sledge. Obviousdly easy to do with the block on an engine stand.
Getting a stuck cam out will be a challenge.
Disassemble as much as you can, buy lots of PB or liquid wrench, and apply liberally. With luck, the block can be machined.
Melting Slicks
Joined: Jun 2009
Posts: 2,709
Likes: 3
From: Savannah GA
Pull the valve covers and oil the heck out of the valve springs, then using a hardwood dowel and a small hammer pop the rocker arms on top of each valve lightly... the valves tend to stick in the guides and add resistance to turning. I discovered this on a Triumph TR6 engine I attempted to free up in my youth... I applied enough force to the harmonic balancer with a strap wrench that I snapped a rocker arm clean off. If they're really seized, remove the rockers and bump each valve directly on the top. Freeing the valves individually has been a part of each "get it freed up" project which has followed.
Pro
Joined: Jun 2009
Posts: 613
Likes: 3
From: Fleetwood PA
pull it, hone it, build it. Not what you want to hear I'm sure, but it will need to be honed(if not bored) at the least. If your not sure it's the rings, you'll have to pull the heads at the very least to see if there is rust in them.
Melting Slicks
Joined: Mar 2005
Posts: 2,095
Likes: 299
From: Midlothian VA
1970, 350/350, 4spd car been sitting garaged for 20 years. Engine is stuck, pistons and cylinders are soaking with Kroil now. How much torque can I apply to the bolt at the front of the crankshaft before I either strip the crankshaft threads, strip the bolt threads, or snap the grade 8 bolt? The normal tightening torque spec for that bolt is 100 pounds as I recall. I have applied 100 pounds with my torque wrench, no movement yet.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Pull the valve covers and oil the heck out of the valve springs, then using a hardwood dowel and a small hammer pop the rocker arms on top of each valve lightly... the valves tend to stick in the guides and add resistance to turning. I discovered this on a Triumph TR6 engine I attempted to free up in my youth... I applied enough force to the harmonic balancer with a strap wrench that I snapped a rocker arm clean off. If they're really seized, remove the rockers and bump each valve directly on the top. Freeing the valves individually has been a part of each "get it freed up" project which has followed.
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Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Pulling the engine and doing a rebuild is in the works, but not in the near future. Over the years, I have had great success freeing up stuck GM engines, Chevrolet, Pontiac, etc. It takes time, but once free, all the previous engines ran great and did not smoke or burn oil or have any problems from being stuck and then free. It is my opinion, that a lot of Forum memebers are way too quick to jump on the "yank the engine and rebuild it" train. Many times it is not needed for the near term.
Melting Slicks
Joined: May 2010
Posts: 3,169
Likes: 2
From: Cemetery of a town Montana
Thanks for the thread, I'm in the same boat with my '70. I've PBed the hell out of it. If it doesn't free up this week, I'll drop another 350 in it this weekend for summer use while I rebuild the original.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
You know, that sounds like a good idea! My 70 has only been soaking a few days, so I will give it more time. But, I could just drop another 350 in it for now and enjoy the car the rest of the summer. I like this idea, something to think about.
Racer
Joined: Nov 2009
Posts: 332
Likes: 1
From: Watkins Glen New York
"I've been able to remove stuck pistons from the bottom by using a cut off wooden broomstick (1 1/2" diameter, couple of feet long) place it INSIDE the piston from beneath, then whack the living crap out of it with a 2 pound sledge. Obviously easy to do with the block on an engine stand."
Not so hard in the car, especially in a Corvette.
Maybe since the oil pan is so easy to remove in these cars, knocking on them from underneath is a viable option. I would want to drop that pan and have a look around and at the oil pump anyway.
Not so hard in the car, especially in a Corvette.
Maybe since the oil pan is so easy to remove in these cars, knocking on them from underneath is a viable option. I would want to drop that pan and have a look around and at the oil pump anyway.
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
1970, 350/350, 4spd car been sitting garaged for 20 years. Engine is stuck, pistons and cylinders are soaking with Kroil now. How much torque can I apply to the bolt at the front of the crankshaft before I either strip the crankshaft threads, strip the bolt threads, or snap the grade 8 bolt? The normal tightening torque spec for that bolt is 100 pounds as I recall. I have applied 100 pounds with my torque wrench, no movement yet.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
IF it's a four speed car, I've popped a couple different ones loose by towing at slow speed and making the rear tires slide a bit- 4th gear and bounce around with the clutch.
If the Kroil or PB doesn't get it, as a last resort, try Hoppe's #9 gun solvent. I've had that work when all else failed.
If the Kroil or PB doesn't get it, as a last resort, try Hoppe's #9 gun solvent. I've had that work when all else failed.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Well, here is the latest. I pulled the valve covers and all the valves are free, not stuck at all. Inside the valve covers looked like it had just been driven and parked, still had oil sitting on the rockers, etc.
So, an old timer I know suggested I drain the cooling system and fill it with warm water, the idea being that a little warmth would make things expand, and possibly help the oil get to the rings, etc. The cooling system was already empty, so I begain filling it with warm water. I got it about half full, when water started running all over the garage floor!! I could not see where it was coming from, but it appeared to be running down the back side of the engine. So, I am thinking bad gasket, rotted freeze plug, or worse, a crack somewhere.
Either way, the decision has been made for me, the engine must come out. Not what I wanted to do at this time, but I have no choice now. I just hope the previous owner didn't let the engine freeze, and crack the original numbers matching block!!
Thanks for all the help and great suggestions. I will let you know what I find.
So, an old timer I know suggested I drain the cooling system and fill it with warm water, the idea being that a little warmth would make things expand, and possibly help the oil get to the rings, etc. The cooling system was already empty, so I begain filling it with warm water. I got it about half full, when water started running all over the garage floor!! I could not see where it was coming from, but it appeared to be running down the back side of the engine. So, I am thinking bad gasket, rotted freeze plug, or worse, a crack somewhere.
Either way, the decision has been made for me, the engine must come out. Not what I wanted to do at this time, but I have no choice now. I just hope the previous owner didn't let the engine freeze, and crack the original numbers matching block!!
Thanks for all the help and great suggestions. I will let you know what I find.
