Why am i not getting spark to my sparkplugs on my 65hp mercury 3cylinder thunderbolt ignition

SOURCE: i have a 1976 65hp mercury outboard how do i change the oil

The drain/fill hole are the same. Put a coffee can or something like that to measure the amont of oil that comes out. Check with a boat parts, or marine or sporting goods section of biggy store. They (at least to) make a pump assembly with hose and threaded end that fits into the hole for the lower unit screw. the other part of the pump fits in a gear oil quart bottle. 80 or 90 is no matter, but needs to say marine grade or suitable for marine use. Nothing special, Penzoil for sure and I think a company Lubrite plus many others make an OK oil. Anyway, put the pump in the bottle and put back in as much as drained out. The level may be marked on the side of the lower unit. If you don't get almost as much out as you put in, check for leaky seal too.

SOURCE: my spark plugs are not firing on my 1973 65hp

check to make sure plugs are ok,next check plug wires ,last check the coil.