Brand new 3.0 mercruiser engine have spark, have gas, timed. No start.

[Steve8686]

EST ignition brand new. Have wet plugs on 3 and 4 dry black plugs on 1 and 2. Gas is new. Have spark on all 4 plugs, New fuel pump, plunger is shooting gas into the carb. ????? Dosent even try to fire. Just cranks over. ????? Actually did this same exact thing with the old engine I just pulled out a week ago but beings it was hovering around 100 on compression and 40 years old I decided to put a new powerplant in. Well, looks nice sitting in there but same problem.

 

[Maclin]

Re: Brand new 3.0 mercruiser engine have spark, have gas, timed. No start.

I would double check firing order and then distributor orientation.

 

[jeffyjeff]

Re: Brand new 3.0 mercruiser engine have spark, have gas, timed. No start.

Bad kill switch?

 

[NHGuy]

Re: Brand new 3.0 mercruiser engine have spark, have gas, timed. No start.

Put a tablespoon of fuel down the carb and see if she fires. If not I'm with Maclin. It should not be the kill switch if you are getting good spark, but it could easily be mistimed or have wires to wrong holes.
Does it seem to crank normally? Fully charged battery? In Neutral/start throttle mode, 2 or three pumps of gas, 1/8 throttle and hit the starter?

 

[Steve8686]

Re: Brand new 3.0 mercruiser engine have spark, have gas, timed. No start.

Thanks guys. Ya, I found TDC on #1 cylinder more times than I care to count. We even switched the spark plug wires around with funny firing order just to try and get a change. Made little difference. I finally broke down and took it to a mechanic, this will be interesting. "Heres a new motor I cant get it to run". Ya I also tried all throttle positions, cranks fine, just no start. It tried to start a couple times but then just died like it was running on 1-2 cylinders.

 

[Maclin]

Re: Brand new 3.0 mercruiser engine have spark, have gas, timed. No start.

Thase are exact symptoms of wrong firing order on plug wires. or the engine is trying to run backwards :faint2: