I have been wanting to do this for a long time and it's way over due. I will be working on this page for awhile so keep checking back for changes and new information.
You can get everything you need for a tune up at a Napa dealer or other parts stores. Echlin is Napa but can be cross-referenced to other numbers.
Engine: Four cylinder "L" head type
Bore: 2.2" Stroke: 3.0" Displacement: 45.6 Cubic Inches (750 cc)
Developed horsepower: 13 @ 3100 rpm
Compression ratio: 5.0 to 1 (before engine number L-15038) 6.0 to 1 (after engine number L-15038)
Compression pressure ~97 pounds
Tappet clearance: .006" intake and exhaust (hot) my experience is that hot and cold settings are the same, better a little loose than too tight.
Ignition timing: ~.020" BTC measure with an indicator through the spark plug hole. For best results at approximately 2,000-3,000 rpm, under a load (driving conditions) advance spark until the engine pings ( a warbling thudding sound) and then retard it until the pinging just goes away. This may take some time but it is well worth the effort to achieve maximum performance.
Firing order: one, three, four, two (1 3 4 2)
1930-32 A.E.A tune-up specs.
1933-35 A.E.A tune-up specs.
Oil 30 wt 2 1/2 qts Castrol GTX 5-30 or Syntec 5-30
Engine: Four cylinder "L" head type
Bore: 2.2" Stroke: 3.0" Displacement: 45.61 cubic inches (747 cc) (1938-39)
Bore: 2.26" Stroke: 3.125" Displacement: 50.14 cubic inches (821 cc) (1940 3 main)
Developed horsepower: 20 @ 4000 rpm (1938-39)
Developed horsepower: 23 @ 4300 rpm (1940 3 main)
Compression ratio: 7.0 to 1
Compression pressure: ~90 pounds
Tappet clearance: .006" intake and exhaust (hot) my experience is that hot and cold settings are the same, better a little loose than to tight.
Ignition timing: For best results at approximately 2,000-3,000 rpm, under a load (driving conditions) advance spark until the engine pings ( a warbling thudding sound) and then retard it until the pinging just goes away. This may take some time but it is well worth the effort to achieve maximum performance.
Firing order: one, three, four, two (1 3 4 2)
1938 A.E.A tune-up specs.
1939 A.E.A tune-up specs.
1940 A.E.A tune-up specs.
Same as above except list below
Spark Plug (1938) Auto-Lite A-9 Champion 844 Gap.025"-.030"
Spark Plug (39-40) Champion H-10 Champion 844 Gap.025"-.030"
Oil 30 wt 3 qts Castrol GTX 5-30 or Syntec 5-30 I recommend changing it frequently (100-200 miles)
You can get them at any good auto parts stores or a battery retail outfit, they may have to order it for you. MG uses two of them in series to get 12 volts.
17HF Negative ground
Napa #'s for materials to make an oil pan gasket
Gasket material: rubberized cork
12"' X 36" #32506 makes 2
18" X 36" #32609 makes ?? more