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MGA MGA w/ Seized Engine

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Geo Hahn

Geo Hahn

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I hear that May 7th is 'Drive your MGA Day' -- but I have a friend who would be delighted if it could just be 'crank your MGA day' cause his has a seized engine.

BTW - the seizing is a result of sitting idle for a long period of time -- prior to that it ran fine.

He's been soaking the cylinders (head still on) with some of the usual concoctions but so far to no avail.

My question -- is there a good way to safely introduce some sudden force to the effort?

For example -- Can an impact wrench get at the crank bolt thru the hole for the hand crank? Is some thumping on the top of the pistons using a wood block & heavy hammer likely to work or just break something?

Any suggestions welcome -- we've got a couple of weeks before we attempt this (really, just happens to be planned for 5/7) if your suggestion require time. Thanks!
 
Check that the starter drive is not jambed into the ring gear. Always look at the simple and cheapest potential problems first. If you have already confirmed that its a stuck engine then good luck with whatever you try next! Bob
 
Yes, check the starter. That's pretty common. But if starter is not stuck, it doesn't sound good.

One thing to try (but I can't guarantee it will work), is to pull the plugs and fill cylinders with kerosene. Then let it sit for a few days. Then put car is 4th gear and gently push the car by hand "rocking" it back and forth (clutch out) to see it that will break the engine loose.
 
No sudden impact as that would REALLY break rings and other assorted bits.

If it were mine, I'd be for dumping the well shaken 50/50 ATF-acetone concoction down the holes. Otherwise the same thing Nial suggests about fourth gear and rocking it back-and-forth after a few days.
 
Thanks for the starter suggestion -- that is a common problem on TRs but I did not know whether MGs also suffered that fate. Easy enough to deal with as they usually pop loose with no more than a bit of rocking backwards in 4th gear. We'll try that first.
 
One other "trick" I've read about is to find which cylinder is closest to the top, release the valve train so both valves are closed, adapt a grease gun fitting to fit the spark plug hole, and pump grease into the cylinder. Because liquids - grease - can't compress, the piston must move. This much the same principle that elevators and car lifts work from. A little pressure from the grease can create significant force on the piston. I may not have all the facts just right but you get the general idea. I'm sure smarter minds than mine will correct me if needed. :laugh:
 
I had the same problem with an A I bought. Used Acetone/tranny fluid in all bores, let sit for a week. Then used a breaker bar and socket on the crank to rock it back and forth until it broke free (the radiator was out). I then ran the car for about 30 miles but it was way down on power. Checked compression and found it to be almost non-existent on #1, and down on #4. After pulling the head, it turned out to have been seized in the #1 cylinder due to rusted rings. Apparently there was a tiny casting leak in the intake tract that allowed coolant to go into the bore and rusted up badly while it sat for a year.

The amazing part is that the rust area in the bore took a huge amount of metal out of the cylinder wall. There's a round depression in the cylinder wall that must be at least 1/8th to 3/16" deep, about 1/4" in total height. I doubt it can even be sleeved it's so deep.

I cannot see how the engine even ran, and that it didn't smoke, or over heat.
I've never seen or heard of anything like this before.

Good luck with yours!

--Jack
 
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