Electric, wants to fire but. . .

[dwkamins]

My '75 seems to want to fire, and I believe it is due to the heat on the head and muffler, but just won't run. Just did the gaskets in the carb and indeed it's getting fuel. new coil. Plug, Points and timing are all correct. I can only think about a short or I thought someone mentioned contacts on the strt/gen? would like to see this run again. . . Any thoughts?

Thanks for the help.

[Whitespider]

These things are not difficult to get running… just a matter of making sure you have 5 basic things.

1) Good spark at the proper time, which requires the following

• A good battery with at least 12.5 volts and some amount of reserve capacity
• A properly gapped spark plug of the proper heat range
• A good plug wire
• A good coil properly wired (B- goes to the points)
• Properly gapped points connected to a good condenser
• Proper timing
• Engine block well grounded to B-

2) Fresh clean fuel (not old stale fuel) properly delivered to the cylinder, requiring the following

• Good fuel lines that do not collapse under vacuum
• A properly operating carburetor and fuel pump (the pump is part of the carb)
• Good engine vacuum (runs the pump and pulls fuel into the crankcase)

3) Good engine vacuum, requiring

• Good crank seals
• Good crankcase and cylinder mating gaskets
• A good crankcase free from cracks or any other leaks
• Good carb mounting and intake manifold gaskets
• Good piston and rings, mated properly to good cylinder
• Open (non-plugged) cylinder ports (intake and exhaust)
• A good, well sealed, properly operating reed valve

4) Good engine compression, which requires

• A good cylinder free of cracks or leaks
• A good piston, properly fitted to the cylinder
• Good piston rings
• A good cylinder head free from cracks
• A good head gasket

5) Open (non-plugged) exhaust system.

If you have those 5 things it will run… If it won’t run, at least one of those 5 things is missing.

[tew45]

If you have a spark at the plug (timing correct) Fuel in the combustion chamber then I would check compression. Ideal is around 90 PSI!

[dwkamins]

Thanks for your info. On the coil, there is a + and a - terminal. Which is the proper hook up to the breaker?

Thanks

[tew45]

negative to the breaker!

[tew45]

Or negative to the breaker points and + to positive of the battery.

[dwkamins]

Thanks for the input!!

I do have a new carb and muffler so those issues are gone. Will be checking ohms and timing again. Also compression check. Will get back with results.

dk