Seized engine on 70Lt1
Thread Starter
4th Gear
Joined: Jul 2009
Posts: 4
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From: NY
Seized engine on 70Lt1
i recently moved my 70Lt1 out of storage. its been sitting for 15years and was not properly put away. upon inspection i found the engine is seized. a friend recommended i put it in 4th gear and try pushing it. any ideas on getting the stuck engine unstuck??
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
If it is truely seized yo uare in for a rebuild. You can try an "unstuck" it by filling the cylinders up with a rust preventitive or Marvel Mystry oil and let it sit. Try turning it over with a breaker bar on teh crank bolt. If that does not do it, I'll bet it needs to come apart.
The 4th gear trick will bust up a lot of things, don't try it.
The 4th gear trick will bust up a lot of things, don't try it.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
If it is truely seized yo uare in for a rebuild. You can try an "unstuck" it by filling the cylinders up with a rust preventitive or Marvel Mystry oil and let it sit. Try turning it over with a breaker bar on teh crank bolt. If that does not do it, I'll bet it needs to come apart.
The 4th gear trick will bust up a lot of things, don't try it.
The 4th gear trick will bust up a lot of things, don't try it.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
sounds like the rings are rusted to the cyl.
breaker bar will allow a smaller movement than a 4th gear trick.
pull plugs and squirt your choice of anti stick stuff and be patient.
you could snap a ring
breaker bar will allow a smaller movement than a 4th gear trick.
pull plugs and squirt your choice of anti stick stuff and be patient.
you could snap a ring
Tech Contributor
Joined: Jun 2004
Posts: 20,804
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Some penetrating oil and a lot of patience will often get you there if pulling the engine is not an option.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
It is like trying to torque your wheels with an air gun vs a torquewrench. You can feel the resistance being built up.
Either way I feel this engine is toast and will need to come apart.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I would put penetrating oil in each cylinder and leave it sit overnight.Then put the car in 1st gear and rock the car back and forth. One guy in the front and one guy in the back. As said above with some patience you might get lucky.
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Race Director
Joined: Jul 2001
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The breaker bar you feel the resistance and stop. The 4th gear will just go BANG! If it will loosen with a little torque from the breaker bar it might be OK. If it takes the full on grunt or putting a pipe on it forget it.
It is like trying to torque your wheels with an air gun vs a torquewrench. You can feel the resistance being built up.
Either way I feel this engine is toast and will need to come apart.
It is like trying to torque your wheels with an air gun vs a torquewrench. You can feel the resistance being built up.
Either way I feel this engine is toast and will need to come apart.
You'll put a lot more torque on the engine with a breaker bar than by pushing the car in 4th gear........................
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
If it is truely seized yo uare in for a rebuild. You can try an "unstuck" it by filling the cylinders up with a rust preventitive or Marvel Mystry oil and let it sit. Try turning it over with a breaker bar on teh crank bolt. If that does not do it, I'll bet it needs to come apart.
The 4th gear trick will bust up a lot of things, don't try it.
The 4th gear trick will bust up a lot of things, don't try it.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 121
From: Millington Illinois
St. Jude Donor '08-'09
I have done this a half dozen times with great results. Pull the plugs and squirt in a rust buster like Kano or Marvel Mystry oil or, what I like best, automatic transmission fluid. Let is sit, not just overnight, but a few days. Put a socket and breaker bar on the crank bolt. If you get it to move just a little, then try and turn it in the opposite direction, moving back and forth, and it will free up. Take your time, it will free up. I have done this on cars sitting 25 years or more with no problems. The rings are just stuck to the cylinders.
Banned Scam/Spammer
Joined: May 2009
Posts: 17
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From: Glendale Az
Be careful turning that crank bolt. I have seen crank snouts stripped that way. That one bolt isn't meant for turning over a stuck engine. It may be fine for a lightly seized engine but yours may or may not be so easy. Just be careful and if it doesn't give then I would pull the engine and take it apart.
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
Be careful turning that crank bolt. I have seen crank snouts stripped that way. That one bolt isn't meant for turning over a stuck engine. It may be fine for a lightly seized engine but yours may or may not be so easy. Just be careful and if it doesn't give then I would pull the engine and take it apart.
I would use a prybar on the teeth of the flywheel instead.
Tech Contributor
Joined: Aug 1999
Posts: 15,124
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From: Connecticut, USA
I dunno, if it's a real LT-1 and was my car, I think I would be doing the whole drivetrain & brakes anyway. I've had bearings go bad sitting in trans for a few years, same with the diff. Brakes are probably mush and will need new calipers, hoses, lines, and M/C. So why not go through the engine? Granted cost & time are a consideration, unless you're just trying to get it running to sell?
Good luck with it. Nice cars those LT-1's.
Good luck with it. Nice cars those LT-1's.
Drifting
Joined: Aug 2008
Posts: 1,381
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So please tell us why the breaker bar is OK, but 4th will bust up a lot of things.
The soak and wait method will work just about every time. I have done it a few times over the years. I use a 50/50 mix of diesel fuel and ATF. About 20 years ago I bought a 1935 John Deere tractor that had been sitting outside since the mid 1950s - soaked it for about week. Every day I could rock the engine forward and backwards a little more with a 2' breaker bar, by the end of the week it broke free. It ran OK, but smoked when cold. The cylinders were pitted terribly in the area above where the pistons had rested all those years.
Tech Contributor
Joined: Jun 2004
Posts: 20,804
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
If you have to ask this question you should let somebody else take over.
The soak and wait method will work just about every time. I have done it a few times over the years. I use a 50/50 mix of diesel fuel and ATF. About 20 years ago I bought a 1935 John Deere tractor that had been sitting outside since the mid 1950s - soaked it for about week. Every day I could rock the engine forward and backwards a little more with a 2' breaker bar, by the end of the week it broke free. It ran OK, but smoked when cold. The cylinders were pitted terribly in the area above where the pistons had rested all those years.
The soak and wait method will work just about every time. I have done it a few times over the years. I use a 50/50 mix of diesel fuel and ATF. About 20 years ago I bought a 1935 John Deere tractor that had been sitting outside since the mid 1950s - soaked it for about week. Every day I could rock the engine forward and backwards a little more with a 2' breaker bar, by the end of the week it broke free. It ran OK, but smoked when cold. The cylinders were pitted terribly in the area above where the pistons had rested all those years.
Racer
Joined: Feb 2009
Posts: 343
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From: San Diego CA
The only way I would spend much time trying to free this engine up without pulling it out, is if I was actively trying to sell the car and needed to get it running first.
Drifting
Joined: Apr 2008
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From: Lexington Park Maryland