Engine not starting - a thread for/about trouble-shooting newbs

[paddington]

Hey All, I have an '79 C&C 27 with an A4. It's been rock-solid for 8 years. I have really enjoyed the motor.

This spring - not starting. I am new at engine mechanic stuff. I am trying and learning. So I thought I would start a thread to seek your thoughts and document my process for other newbies like me. I have been reading a lot here and have been following advice. What a great site!

I'm certain this will sound familiar:
- motor was running in fall
- had become progressively harder to start over time
- started to stumble/hesitate when accelerating from idle but recovered at cruising speed and ran fine
- some white smoke at startup but it went away as motor warmed
- returned in spring to a not starting motor.


Some details about my engine:

1979
4-bolt carb (zenith 68 I believe)
electronic ignition
electric fuel pump (EP8016SP)
ignition coil new in 2013
freshwater cooled
oil pressure always 30 psi at cruising rpm
temp always at 130F at cruising rpm
good batteries on shore power trickle charger


This is what I have done:
1. SPARK - confirmed spark in all for plugs. Yellow spark (not blue) in each
- installed new plugs (RJ12YC gapped at .035), new distributor, fresh (but not new) rotor, inspected leads

2. Compression - squirted 7 drops MMO in each plug hole and turned engine over. IN morning I took out all plugs, ensured choke was open and throttle was wide open, did cold test and got 115, 100, 105, 95 values.

3. Fuel - new Racor filter, confirmed fuel pump operating, removed carb and disassembled and cleaned with carb cleaner and compressed air into all orifices. reassembled and reinstalled.

4. Made sure the freshwater seacock intake was closed during all this cranking - thanks guys!

Still not starting. Tried spraying gas into air intake while cranking. no dice.

What I have not done:
1. I have not been super good about winter shut down maintenance. I used to start it every week and run against dock lines for 10 min until warm. When I moved the boat to Pender Harbour from Vancouver, running motor through winter became less frequent. I didn't run it at all last winter.

2. drained the fuel in the tank. The fuel in the racor filter is clean and sludge/water free


I'm a little perplexed at the non-starting given there is spark (weak?), compression and fuel .

I am considering a carb rebuild or new one. I will replace the coil and the rotor with new. I have new plug leads if needed. I have a new fuel pump if needed.

I will post updates as I trouble-shoot this. In the meantime I am considering mounting an outboard on the transom until I get the A4 working.

Thanks to all for a helpful community.
Barry

[JOHN COOKSON]

Check to be sure the choke is closing all the way.
Don't like the yellow spark. Do you have points or an electronic ignition? The coil may be on it's way to not working at all.

TRUE GRIT

[paddington]

Thanks John. It's helpful to hear from experienced folks. Yes, electronic ignition and i ensured choke is closing fully.

A new coil will go in. Crossing fingers that takes care of it.

Barry