1936 Chevrolet 206 straight Six Engine

[Guest rodger with a d]

Hi, a newbe but need some help. I rebuilt my 206 several years ago and drove the car some 5000 mile without issue.

I was unable to drive the car for some time 5 years or better.

It was running fine when I put the car on blocks to store the car until I had time to use it.

Now retired and able to have fun the car engine is an issue.

The engine will not rotate, I mean really stuck.

Cannot move the engine with the crank without spark plugs.

I have put transmission fluid mixed with Acetone soaked it and no luck will not budge.

I pulled the valve cover and all the push rods look great none bent, that are not under load from the cam.

The valve train is very clean and look perfect.

I pulled the starter and tried to pry the engine on the flywheel teeth again will not budge.

I am hoping for some insite here as to what may have happened.

Crazy from running fine to this.

For you who are willing to help I thank you in advance

Rodger

[Bhigdog]

The pistons, or perhaps just one, are no doubt frozen to the wall. It's amazing how little it takes to seize them up. What you are doing is correct you need to do more of it. It may take a day of soaking. it may take a month. Keep soaking and trying to move the starter ring. Use a substantial pry bar not a wimpy screw driver. If it moves just a fraction you will be OK freeing it. Then add more juice and work back and forth. Once it's loose and no juice in the cylinders change oil and see how it runs. Best case it will be fine. Not so good case you have broken and/or seized rings. Worst case it won't break free and you are looking at a tear down. Good luck. Patience is your friend here.................Bob

[Curti]

My son brought home a 40 Chevy coupe that had sat for 20+ years. The only way it got loaded on the trailer was the clutch had to be depressed. We used ATF and acetone as well. After a few days we pulled the plugs and hooked it up to the tractor and pulled it in 2nd gear , at roughly 15 mph he let the clutch out. It broke loose. we continued to tow it to pump out as much ATF as possible. we put the plugs in and poured a little lacquer thinner in the carb it fired right off and has been running fine ever since. That was seven years ago.

[Guest]

The pistons, or perhaps just one, are no doubt frozen to the wall. It's amazing how little it takes to seize them up. What you are doing is correct you need to do more of it. It may take a day of soaking. it may take a month. Keep soaking and trying to move the starter ring. Use a substantial pry bar not a wimpy screw driver. If it moves just a fraction you will be OK freeing it. Then add more juice and work back and forth. Once it's loose and no juice in the cylinders change oil and see how it runs. Best case it will be fine. Not so good case you have broken and/or seized rings. Worst case it won't break free and you are looking at a tear down. Good luck. Patience is your friend here.................Bob

I'm with you on this one. Rocking back and forth gently is your ticket to not breaking a piston ring.

[61polara]

You can also jack up one rear wheel, put the transmission in low and work the wheel back and forth.

[cahartley]

If it's that stuck chances are the oil rings will never loosen up.......never.

I bought a low mileage '59 Chev with the 235 and got it here Labor Day weekend. It had stood a looooooooong time.......I've smelled a lot of old gas before but nothing even CLOSE to how horrible this was.

Anyway.......the engine was loose and I had it running almost, literally, within minutes of getting the car off the trailer. I first fired it by just dumping some gas in the carb....no lines hooked up.

Then I ran it off a small tank for a bit. I wound up getting a new tank, sender and fuel pump.

Since then I have put maybe 1500 miles on it using Marvel Mystery Oil, Sea Foam and additional detergent additives in an attempt to get the oil rings to free themselves.

NOT A CHANCE........NOT going to happen. It's going to have to be ringed.

Pity because the engine purrs like a kitten.......and drinks oil like an elephant....... :mad:

Edited January 5, 2014 by cahartley (see edit history)

[Lahti35]

You could try pumping hot water through the block then letting it cool a few times along with the ATF/acetone. Time will tell if its ok... you never know. I just pulled the pistons out of a 27 Buick that hadn't turned over since 1946 and all the rings were free, pistons looked great.

My '36 206 has been down for a year with the rocker arms out... A little oil in the cylinders and turning the crank now and then has allowed me to avoid your problem.

[Guest ronb03]

My .2 cents worth. I bought a 36 chevy that was rebuilt in 1985 but never started, same thing soaked cylinders for 2 months with Marvel Mistry oil. Crank wouldn't turn it over. I put a piece of steel 3 ft long in place of the crank, the extra leverage helped my engine to turn over. What a relief! Good luck with your engine!

[Rusty_OToole]

I have revived a lot of engines that have been out of commission for up to 30 years. If it is that stuck I would not force it, not if the engine means anything to you.

Take the head off and see what is the matter. Probably one cylinder is rusted to the piston because the intake valve was open on that cylinder. Your engine uses iron pistons which makes things worse.

For the cost of a head gasket you can look inside and see what is what.

Depending how bad it is, you may be able to free it up and put in new rings, touch up the valves and away we go. By the way rust pits in the cylinder do not necessarily mean the cylinder needs to be bored.

An old mechanic friend told me about an engine he overhauled for an International truck. It had been left outside with the head off and the cylinders were pitted with rust. He honed the cylinders, installed new rings and hoped for the best.

The engine burned a little oil for the first hundred or 2 hundred miles then settled down and ran perfect. A few years later he had the head off for a valve job and found all the rust pits filled with carbon and polished smooth.

So don't worry about a few rust pits unless there is a rusted area big enough to snag the rings.

[Ben Bruce aka First Born]

My newbie won't come back!

Ben