MG Car Repair: 1971 MG Miget, light rust, wd 40

Question
Subject:engine locked solid. We have owned this MG since 1973.It had been in storage for 10 years.I took it out to get it running again and found the fuel tank was leaking. The engine turned over using the starter with no problem.It took 3-months before I got the tank repaired and reinstalled. When I tried to turn over the engine I found that that it was locked up.The cluch is working fine and I can disengage to move the car but in gear it is seiased up.I removed the plugs and the starter to see if that would help but the crank will still not move. I have put the car in gear and rocked it but there is no movement in the crank.I find it hard to believe that the car can sit for 10 years and not siease up but in just three months this happens.Is it possible that something is blocking the flywheel? If it is the pistons it should be just a light rust. What if I put liquid wrench in the cyclinder heads and wait a week then rock the car in 1st gear would that free up the engine? Your in put and help would greatly appriaciated.

Answer
Hi Mark,
Yes, rust on the cylinder walls is the most likely cause. Get a can (not spray can) of something like WD-40 from any auto parts store and put about a quarter to a half of a cup in each spark plug hole and just let it sit for a few days. Then lay a towel or rags over the plug area because if it breaks loose it will spray the excess oil all over the place. Then with the plugs OUT, put the car in HIGH gear not low gear and rock the car back and forth to see if you can break it loose. If you can, hand push the car around a little to expel the excess WD-40. Put the spark plugs in for just enough time to wash the engine down (WD-40 and such is very combustible).

Then you can use the starter to spin the engine with the plugs out and at times put a little engine oil in the plug holes and spin the engine checking the starter motor at times to be sure you don't over heat the starter motor. If it is getting hot, let is set for an hour of so and add a little engine oil to the plug holes and spin some more. It makes a mess but is necessary so as not to do any more damage than what the rust has done.

Then you can confirm that you have ignition and drain the fuel tank and lines and it would be advisable to remove the tops of the float chambers and remove the stale gas with a rag then blow out the last bit with an air hose. At that time you can turn the electric pump on and run a little fresh gas through the lines to expel any stale gas left in the lines. (Keep a fire extinguisher handy) Now you should check ignition timing and change the engine oil and filter.

(DON'T SKIP THIS AS IT IS VERY IMPORTANT) You have contaminated the oil with a lot of rust and WD-40 which is very combustible.
Let me know,
Howard