1972 9.8 mercury outboard wont start, changed spark plugs?

Question

before changing spark plugs engine would start rev up high and in gear would bog down and stop??? Now after putting new plugs in wont start at all...need experienced help, new to boat engines

Answer 1

Sounds like lack of fuel.Spark plugs will indicate cylinder condition...dry= no fuel, wet=too much fuel, no spark or no combustion.Pull a plug and with wire attached ground the threaded part to the motor &crank it over....if you see a spark across plug ignition is not the problem.

Answer 2

Sounds like the wrong spark plugs. Take out the plugs and see if the plugs haven't been smashed shut by sticking into the cyl head to far. Then look in the hole and see if you damaged the piston. If it just has a little mark on the top don't worry about it.

Answer 3

No reason you can't maintain this engine, but you'd want to get yourself a manual

First compression test, then a spark test.  use an inline spark tester set the gap at 1/4" & look for spark while turning the engine over.

good compression and spark on both, rebuild carb.

bad compression, pull cylinder head for inspection.

no spark, troubleshoot ignition system.

Answer 4

1st are you getting spark?  

is fuel flowing to the carbs

could be a bunch of things  check spark first and clean the plugs they might be fowled

Answer 5

You probably need to clean the Carburetor, especially with that year of a engine.