302 getting gas spark but not firing

Question

I have a 85 merc capri 302 its gettin gas and spark but not firing on all cylinders. # 1 and 6 header pipe is cold to the touch. Checked the timing and wiring and thats good. It has been sitting about 3 or so years and have changed the gas and has new filter on it. This is the 2nd motor that has been in it pulled 302 and put 351 init and cant get 351 runing at all so put 302 back in it

Hope someone can help

Thanx!

Answer 1

you may have a wasp nest in the intake manifold

is the spark plug wet?

Answer 2

check valves being stuck on these cylinders. chk compression  

Answer 3

Check the compression at plug nos1and 6.  If theres none,take the tappet rocker covers off !,and check to see if the valves at 1 and 6 are moving up and down,as they could be stuck because of condensation build up which can rust them up and cause them to seize.  The result your car not firing on all cylinders.

                                                 Hope that helps.

Answer 4

i don't know

Answer 5

have you checked all the spark plugs and leads? dizzy & cap?

it might be worth doing a compression test if everything else looks good.

Answer 6

the coil could be bad, or coil pack.

Answer 7

recheck the firing order>& timing>