Chicagoland MG Club: Driveline August 2011
Tech Corner

Pulling a Cylinder Head
Obviously a broken valve spring requires immediate attention, but what about weak springs, especially after up-grading to a higher lift cam? The problem is in determining whether or not to pull the cylinder head.

If the head is not removed, an easy way to keep the valves from falling down into the cylinder is to snake in about three feet of small diameter rope into the cylinder while the piston is at BDC (Bottom Dead Center) of the cylinder and the valves you will be working on.

Rotate the crankshaft, clockwise towards TDC (Top Dead Center) BY HAND, via the crank pulley nut. DO NOT TRY TO TURN IT WITH THE STARTER. In fact, as in any other major repair, it's a good idea to have the battery disconnected to prevent accident or injury. Gradually rotate the crankshaft until light resistance is felt. The valves are held up by the compaction of the rope and no air pressure, coat hangers or trick tools are required!

After repair or replacement, don't forget to re-torque the head and set the valve clearance. On "A" and "B" series MG engines it's also a good idea to add a cooling system sealer to insure there are no leaks, since some of the cylinder head studs come up through the rocker pedestals and removing it MAY produce a leak. However, there is a 90% chance it will be OK after repair.

To remove a stubborn cylinder head try this first. Remove all cylinder head bolts but leave the spark plugs in place. Then crank the starter a few times-just tap it, don't turn it. The compression of the motor should break the gasket seal on the head.

Put A Spin On It!
I've had a problem with certain size spin-on oil filters. It seems my adjustable, one-size-fits-all wrench, just can't get enough grip to spin the filters off sometimes. Now I use a strip of old inner tube about 8" long and 3" wide to wrap around the filters before I apply the wrench. This has always worked on even the most stubborn filters.

Can't Stand Leaks?!
I have come to the conclusion that British cars have a certain amount of leaks considered accepted. For those of you however, who cannot stand leaks, here is my method of locating them.

Purchase some brake cleaner and after cleaning the suspected area, spray it down with Desenex or other aerosol foot powder! Run the engine at around 1500 rpm for around ten minutes and look for the leak. If it's bad enough it will soon show up as the cleaned area with the powder will reveal all.

I have found all types of leaks using this method, from transmission fluid to fuel leaks. Best of all, it cleans up easily!

-- Barney Gaylord  

Toolbox Tips
Excerpt from University Motors LTD. Technical Book - 2007

Drilling—Always start with a very small pilot hole first, then incrementally increase the size until the proper diameter is reached.

Frozen Engine—Soak the cylinders in penetrating oil. Remove all the items on the starter side of the engine— distributor, generator/alternator, even the heater control valve so that you can get a good view and room to use a GIANT pry bar on the starter ring gear. Heave at the ring gear, first one way then the other, until the motor turns on complete revolution. Pull the car around the block at 20mph in second gear, and the engine will completely free up.

Gaskets—Wet a gasket to make it supple and to expand an old dried one. Sealers include grease, silicone, or Permatex. Make a gasket with a small ball peen hammer and the piece to which it will be fitted.

Bolts—Start all bolts in any assembly, then tighten them in a proper sequence. Head nuts, in a spiral; Sump or timing cover, in a cross pattern; and exhaust from front to rear.

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