69 350 Won't turn over
Thread Starter
5th Gear
Joined: Feb 2020
Posts: 5
Likes: 0
69 350 Won't turn over
The car has been sitting in the garage for 20+ years. We turned it over a year or two ago but now it's seized up.
So far we have soaked the cylinders in MMO for 3 weeks and that freed it up enough to get maybe 1/8 a turn with the plugs out using a breaker bar. We also pulled the valve covers and tapped each valve to make sure they move and it seems like they are free but we don't see any rockers move when we get our 1/8 turn.
What else should we be looking at here? Car is obviously in neutral
So far we have soaked the cylinders in MMO for 3 weeks and that freed it up enough to get maybe 1/8 a turn with the plugs out using a breaker bar. We also pulled the valve covers and tapped each valve to make sure they move and it seems like they are free but we don't see any rockers move when we get our 1/8 turn.
What else should we be looking at here? Car is obviously in neutral
Le Mans Master
Joined: Aug 2005
Posts: 6,541
Likes: 1,975
From: Temple Terrace Florida
If you are only looking to free up the engine and the car is a stick, put the car in fourth gear and push it forward. If you only have room only to go backwards, put the car in reverse and push it backwards. If you put the car in neutral, and push it, does the car move? The transmission could be stuck in two gears and locked. If that is the case, it is usually a linkage problem. Jerry
Burning Brakes
Joined: Aug 2013
Posts: 1,071
Likes: 322
From: palm springs ca
Other than rust, I had a 66 BB Chevelle towed in that was rebuilt, but owner couldn't get started. He gave up and the car sat for a few years. It would not turn a bit. We pulled the engine and didn't find rust when we pulled the heads. There was evidence of a white powder in a few cylinders. After failed attempts the owner said to get nasty. We did soak each cylinder before pulling the heads. We took a wooden block and beat each piston top, expecting to replace mega parts. After about 1 hour it turned over enough for us to remove the crank. We then were able to pound each piston down then back up and out. Some needed no force but about 3 had chemically welded themselves to the cylinder. When we got them out the rings were stuck to the point that they would not move. The pistons were white with corrosion.
This all happened in the early 70's. A fellow who worked in the lab at a steel mill said that the gas liquid gasoline that was poured down the carb reacted with the oil and corroded as time went on. He said gas and oil along with the different metals, pistons, rings, and cast iron created it's own combination, along with indifference in metals.
Hope this is not your case and it's just gummed up oil.
Dom
This all happened in the early 70's. A fellow who worked in the lab at a steel mill said that the gas liquid gasoline that was poured down the carb reacted with the oil and corroded as time went on. He said gas and oil along with the different metals, pistons, rings, and cast iron created it's own combination, along with indifference in metals.
Hope this is not your case and it's just gummed up oil.
Dom
Thread Starter
5th Gear
Joined: Feb 2020
Posts: 5
Likes: 0
Thanks for the replies guys, I really don't think it's the transmission but I might as well take a look. Car has a flat tire so I can't really roll it, we've been trying to turn it over with a breaker bar. I did have a look with my boroscope in the cylinders and there's no white corrosion or anything, just a tiny amount of surface rust.
Burning Brakes
Joined: Aug 2013
Posts: 1,071
Likes: 322
From: palm springs ca
One way you might be able to get a good bite (leverage) is turning the fly wheel at each tooth. Air in a cylinder works sometimes. I might add that I had a surface rusted engine (cylinders) and once we ran it the rings wiped the rust and the very small pits actually seemed to hold oil and it ran great till someone stole the truck.
Hope you get lucky. If it runs good then a compression test after a while would tell the story.
Dom
Hope you get lucky. If it runs good then a compression test after a while would tell the story.
Dom
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
few WAGs
timing chain Broke & bound-up around crank sprocket between timing cover
starter drive busted & jammed into ring gear
piston broke & chunk caught between rods or jammed into cylinder wall
timing chain Broke & bound-up around crank sprocket between timing cover
starter drive busted & jammed into ring gear
piston broke & chunk caught between rods or jammed into cylinder wall
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Can you turn it backwards with the breaker bar? Or doesn't loosen the bolt? What you're probably going to have to do, is pull the heads, oil up the cylinders and and get some sandpaper and clean up the boers above the pistons. Make note of which ones you could tell when down instead of up you'll be able to see that mark where the piston was. Now that 1 is going to continue to go down as you try to turn forward. Other ones that went up you could put a piece of wood on top and Bang them with a hammer to try to get it to go the other way. What you may want to do 1st though is get an oil primer of some sort and get oil on to those rod bearings 1st . You can take out the starter and put a big screwdriver in near also to crank the motor backwards.
Last edited by derekderek; Feb 10, 2020 at 10:45 AM.
Racer
Joined: Oct 2001
Posts: 474
Likes: 64
From: Portage La Prairie Manitoba
The car has been sitting in the garage for 20+ years. We turned it over a year or two ago but now it's seized up.
So far we have soaked the cylinders in MMO for 3 weeks and that freed it up enough to get maybe 1/8 a turn with the plugs out using a breaker bar. We also pulled the valve covers and tapped each valve to make sure they move and it seems like they are free but we don't see any rockers move when we get our 1/8 turn.
What else should we be looking at here? Car is obviously in neutral
So far we have soaked the cylinders in MMO for 3 weeks and that freed it up enough to get maybe 1/8 a turn with the plugs out using a breaker bar. We also pulled the valve covers and tapped each valve to make sure they move and it seems like they are free but we don't see any rockers move when we get our 1/8 turn.
What else should we be looking at here? Car is obviously in neutral
If its a manual transmission the clutch plate could be seized to the flywheel
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