Engine Locked Then Free

[Tiger Tim]

Bit of a head-scratcher tonight: I gave my T two pulls on choke to prime it, noting nothing unusual other than a little wheezing through the #4 plug threads, then hit the switch and went to pull it for a start. To my surprise the engine was locked up tight. No give, no play, just zero rotation. I gave it a good, smooth pull as hard as I could and it seemed like I would lift the front wheels off the ground long before the engine would budge. I wondered what would happen if I turned the engine from the other end so I put it in gear and rocked the car back and forth until it was free again. After that it started normally and ran without any new noises or power loss. Actually it probably ran stronger than it has for a while but that’s likely unrelated.

So what was it hung up on?

[DHort]

Starter stuck on ring gear?

[Wayne Sheldon]

How fresh or tight is this engine? Maybe a tight valve hanging up? I have run into that before. If the valve has been hanging up a bit, it could have been not closing completely, resulting in a weak cylinder. Suddenly snapped all the way down and stuck, I have seen that hold an engine from turning by hand crank (nearly lifting the front of the car by the handle!). Once worked loose by rocking the car in gear, the valve frees up and works normally (sometimes!). All it takes is a microscopic metal chip in the wrong place to act as a "Chinese finger trap" on the stem. Once the piece works out, it (usually) gets lost in some out-of-the-way corner and does no more harm.

Just an idea?

[Humblej]

Tom, if it locked up during an electric starter cranking I agree with Dave, that is a classic bendix gear stuck in the ring gear. Only way to unstick a bendix gear is to rock the car while in gear or take the bendix cover off and pull the gear out by hand. Stuck bendix gear common, stuck engine during hand cranking on a otherwise normally functioning engine is bad, like a loose washer or bolt head stuck in the flywheel and mag ring...something catastrophic.

[Tiger Tim]

So what do you guys think is best? Check the bendix spring just to be sure then drain the oil and go magnet fishing in the trans?

[Norman Kling]

If that happened after using the starter, I would agree it was a stuck bendix. However if you were cranking it before it locked up, I would suspect water in cylinder. when it comes up on compression, the water won't compress. But if you can get the engine to turn just enough for a valve to open, the water will run out either the intake or the exhaust. So check for water around the carburetor and out the exhaust pipe. Also check for water in the crankcase which could leak past the rings.
Hopefully, the starter because easier to fix.
Norm

[Humblej]

I like the idea of water/coolant in a cylinder. If it is water there will be some in the oil pan too. Running an engine with water in the oil pan will cause the oil to look like a milkshake. Just drain the oil and see what it looks like. Norm may have called this one.

[Tiger Tim]

I’ll have to drain the oil and see what I have. I peeked in the rad and the level looked about normal but on the other hand the engine still tweets a little under heavy load so the head gasket can’t be 100% perfect. For what it’s worth there was no water under the car and no steam or anything out the exhaust after start up.

[Scott_Conger]

The description of the lockup was one of hand cranking...no starter involved. It cannot be the bendix if the starter was not energised. There seems to be both crucial information missing from the starting sequence, and large assumptions that the starter was involved during a hand crank - a fact that I do not discern in the description.

Loose parts that will lock up a transmission will nearly always show themselves as a wicked racket once the engine starts. The engine was ultimately started, and there was no noise...To be fair, though, I have personally driven a car which had an exploded magneto in it and it was miraculously silent for the 5 miles the car was driven, as all renegade parts were firmly wedged out of harm's way. A bouncing trip across America on a trailer, shook all the parts loose and the entire thing was hopelessly locked up until complete disassembly. That was the first I knew the magneto was blown up (I had purchased the car as a derelict). I believe this is a huge exception to the rule.

If more, clear information was forthcoming, there would be fewer guesses and more solid advice. As it is now, it is simply speculation and guesses.

Since we're guessing, and that's fun if we're not the one paying the bills...the description is that of a complete and total lock up which a small amount of water in a 4:1 compression engine will not give...however, a missing cotter on the crankshaft pully pin will do exactly what was described, by dropping the pin through the pan, and has the capacity to "go away" when the car is rocked backward, and possibly not be an issue again for awhile. Or it could tear up the pan tomorrow...

Never fear though...that's just a W-A-G.