Boss 302 engine locked

[iamlance]

A friend of mine has a 70 Boss 302 that has been in his barn for about 12 years. Car ran fine when parked. We tried turning the motor over with a breaker bar and socket on the dampner but it won't budge. He put mystery oil in the cylinders and left it for a few days and tried again, no luck. Any suggestions??? (other than hanging him by his ba!z for letting this happen)
He's owned the car since 72. All original, no shaker, no slats, 74K miles. What a dope.

 

[gjz30075]

Use some PB Blaster. Great stuff. Let it sit for a few days, then spray some more. Make sure you're in neutral, too.

 

[dennis112]

Use some PB Blaster. Great stuff. Let it sit for a few days, then spray some more. Make sure you're in neutral, too.

Also, remove the starter or bellhousing lower cover and pry there instead. You should be able to get a little more leverage.

On second thought, if it is that froze up the a rebuild is in order. Pretty sure the rings will be trashed and the pistons will scuff if you run it. :damnit:

 

[ashford]

fill her with diesel down the spark plug holes and let it sit then tow it and let out the clutch. my brother did this to his 57 and the thing ran aferwards and killed all the mosqitoes within a 3 mile radius

 

[Hack]

I wouldn't try to start it either. That engine is worth too much to do that with. It should be pulled apart as gently as possible. Hopefully he will be able to get away with a hone on the cylinders. If you break it loose I would think your odds of making a big scratch inside a cylinder are higher.

 

[johnsstang04]

Rebuild it.... don't even think of turning it over. I have seen many engines damaged because people attempted to turn them over while they were ceased.

 

[65stang289]

I would go the PB blaster way and give her hell if that does not work then take her apart

 

[johnsstang04]

I just don't think its worth taking any chance of screwing the engine up. Clearly there was nothing wrong with it before it was put in the garage, so why mess it up now.

 

[10secgoal]

Pull that piece of junk out and send it to my house.

 

[iamlance]

It's a boat anchor!! I told him to put a small block chevy in it.

 

[D.Hearne]

I wouldn't try to start it either. That engine is worth too much to do that with. It should be pulled apart as gently as possible. Hopefully he will be able to get away with a hone on the cylinders. If you break it loose I would think your odds of making a big scratch inside a cylinder are higher.

I second this 100% Or just give up and hand it over to me.

 

[Hack]

Or just give up and hand it over to me.

Now why didn't I think of that??

:damnit:

 

[10secgoal]

I second this 100% Or just give up and hand it over to me.

You'll have to wait for it, I posted it first. I don't really want it at my house, but I would help him out to get it off his hands though.

 

[krash kendall]

fill her with diesel down the spark plug holes and let it sit

This does work well, just not completely recommended for this car/motor. A Honda civic or Pinto wagon maybe?

 

[ashford]

any way you look at it you need to free the pistons from the cylinders. the two ways of doing it is in the car or on the stand. in the car you pull it then let out the clutch in high gear or on the stand you have to pull what piston out you can then pull the crank then hammer the remaining piston(s) out. i had to do this to a 289 once, later i took it to a machinist and a .030 bore didnt clean it up a .040 barely took care of it.
doing it in the car is easier, and no you dont have to start it just turn it over once or twice. doing it on the stand is a bit more delicate, and a whoops here can cause more damage than trying to pull it.

 

[mustang70]

I've heard of people using ATF to help unlock pistons. Pour some into each cylinder and let it soak over night.

 

[D.Hearne]

I've done the ATF thing lots of times, I just don't recommend it in this case, not with a rare and valuable engine as an original Boss 302. Neither would I ever contemplate "pull" starting it to free the pistons. You'll likely do irreparable damage that way to more than just the engine. Good way to damage the rearend and transmission.

 

[10secgoal]

I guess if the block were out, you could pull the pistons thru the bottom of the motor. Won't come completely out, but far enough down you could break and remove the rings. This would give you a little more room to slide the out the top. Or if you left them down, you would have tons of room to work with the cylinder walls, to get them clean to slide the slugs out.