No compression

[sastanley]

ALMOST THERE!

Marty...compression = good, fuel on plugs = good, spark = good, but still won't run..now is the time to re-check timing. I recommend you start from scratch to make sure it is set correctly.
Teach them how to set the motor to TDC (can you access the front of the motor to turn by hand/view roll pin?) and then make sure the rotor is pointed at #1. One tooth off on the distributor gear will make it very difficult to start/run. We just went thru this procedure with my buddy's C-30 a couple weeks ago, and all three of us that were there are gear heads, but, it finally ran after setting timing from scratch.

If you get it all lined up, you can adjust the distributor while cranking, just watch out for moving parts, or move it a little and lock it down in between each attempt until it fires. After some run time, you can set the timing for cruise RPM. One last check, especially since it is EI, make sure the dizzy weights under the EI plate are free!

[JOHN COOKSON]

Be sure the choke is closing all the way.

TRUE GRIT

[Marty Levenson]

spark

Thanks - want to get a good spark first. Then timing!

Pretty sure not the coil or battery....how could one plug have a blue spark otherwise? Likely connections to distributor towers or plugs, ign wires, gap on plugs, or plugs themselves (least likely: new) ....

[Hawkeye54]

Spark plug firing order

Marty, just a reminder - since the distributor cap was removed - have them check for the correct firing order on the plug wires

Rick

[Marian Claire]

Post 13 "yellow spark at three cylinders, and a whiter spark at one"
Post 18 "one plug have a blue spark"
I'm confused. I can say that when my coil failed I had weak/yellow spark and a non-starting A-4. With a new coil the spark was blue and strong with instant start up. A world of difference.
Dan S/V Marian Claire

[JOHN COOKSON]

I don't trust the "mechanic" that worked on the engine previously.
If by any chance the spark plug wires are graphite core not solid core toss them and replace them with solid core wires.

TRUE GRIT

[Marty Levenson]

update

Thanks for your replies.

I spent some time at the boat today, and also had a chance to speak with the mechanic.

He stated that his compression test two months ago was very low (35 - 70) and a wet comp test brought the numbers up a little. But now we get good numbers (85 - 100) on a cold, dry test. I do believe him: he has a solid reputation on our island, and just seemed real. Even added that he calibrated his compression gauge and rechecked. Wondering if the oil he put in the cylinders and/or more cranking loosened up the valves? I have not messed with the valves directly as the compression seems good enough to allow the engine to start.

I never saw a good spark, though all plugs had yellow spark. The batteries were very low, so it hardly cranked. My plan is to charge both batteries fully, change the coil, and give it a try.

The wires seem to be in the correct order (1243), and we used my spare wires, which I know worked last time they were deployed.Plugs look new and are now gapped. Ignition is electronic. To repeat, rotor and cap are good, known spares. Gas is getting to the plugs. The carb was rebuilt recently.

Frustrating but nothing to do without batteries: they are on a government dock with no power available so charging the batteries at home.

[Quentin_D]

Hi all,

I am the co-owner of the C & C 33 and its Atomic-4!

Thanks for all your replies. It is very helpful for beginners like us. And a special thanks to Marty who learned a lot while we did not even know how to start it (or try to).

As Marty said here, the compression looks fine (80-100 psi) and spark plugs smell gas.

The battery looks pretty low and we charged it for about 4 hours with a 2A charger. We could not load it more as there is no electricity at the dock and we had to leave the island where the boat is.

After that, when we tried to start it, it ran pretty fast as if it almost started but then, after 20-30 seconds that we had begun to push the starter button, it brutally slowed down while we were still pushing on the starter button.
We tried 3-4 times and always the same behavior.

Do you think it is just because of the low battery or it can also comes from the ignition system ?

[JOHN COOKSON]

I never saw a good spark, though all plugs had yellow spark. The batteries were very low, so it hardly cranked. My plan is to charge both batteries fully, change the coil, and give it a try.
.

Get the batteries fully charged then pull the wire out of the center terminal of the distributor, hold it near the near the engine and then crank and see what kind of a spark you get. If the spark is puny then the coil is suspect.
Maybe the reason the mechanic got low compression numbers is because the battery was not charged adequately?

TRUE GRIT

[Marty Levenson]

Plugs

Found the answer to the below question. (Robert Hess's old site)

Still helping the new boat owners.

While the batteries are getting an extended charge I pulled the plugs to check the gap. They are NGK BR6S. I looked up Atomic 4 on the NGK site and find they list B6S (no "R") for the A4.

Anyone have experience with these plugs - are they compatible?

Thanks!

[Dave Neptune]

Marty, same plug but the "R" stands for a resistor plug a plus for the A-4. I always used the RJ12C which is a resistor style and marine grade with the copper core ie the "C".

Dave Neptune

[JOHN COOKSON]

After that, when we tried to start it, it ran pretty fast as if it almost started but then, after 20-30 seconds that we had begun to push the starter button, it brutally slowed down while we were still pushing on the starter button.
We tried 3-4 times and always the same behavior.
Do you think it is just because of the low battery or it can also comes from the ignition system ?NO THERE IS A THIRD ONE

Maybe this has been mentioned already.......
Have you checked the wiring? The end connectors need to be clean and bright and no corrosion of any kind in the wiring itself. This includes the battery terminals. Check both sides of the circuit - hot and ground side. The hot side will be a red wire ~ big around as your little finger. Maybe bigger. Check all of this wiring battery -> starter. The ground side will be a black wire of similar size most likely battery->engine. Give this a look see also. You may need to disconnect the wires to check them adequately. Please note if the wiring can not carry adequate electricity to the starter it will appear as if the batteries are discharged.
I guess you know to determine if a battery is fully charged you can take a specific reading?
The starter may be pulling so much current through marginal wiring there is not enough electricity left to correctly fire the spark plugs.

TRUE GRIT

You're getting closer to a running engine. Stay with it. Aren't boats fun?

[Quentin_D]

I didn't check the battery terminals. I will do it this weekend !

Yes boat are fun ! But it will be even better when the A4 will run and we'll be sailing

Hopefully it will run this weekend !

[Ken Rockwell]

First try hooking the battery to the coil, if it doesn't work try filing the points, also bring a spare coil. I think you have enough spark to make it fire. Try draining the float in the carb before you crank it. I think you may have a carb issue. The starting and running fast and dying might mean some kind of air leak. Maybe someone took it appart and ripped the gasket. Disconnect the fuel line going into the carb and make sure it's pumping fuel. Also see if the carb bolts are tight maybe it's something simple. Maybe someone put the float in upside down, I've done that more than once. Wet plugs could mean flooded. In fact make sure the needle valve is sealing. And make sure the floats aren't full of fuel, this is uncommon but it happens.

[Marty Levenson]

spark - comp - gas

To recap: First we confirmed compression as the mechanic had found it very low a few months ago. Seems good now. Put some MMO in all cylinders to sit for a couple days.

Now we are working on getting a good spark. Initially there was none - so changed ugly rotor and got spark on some plugs. Changed cap and wires and have weak spark on all. Battey was too low to continue, so returning to the boat today with two charged batteries. Have a spare, good coil, so if no good spark at the coil primary wire today, we'll change the coil.

If no start will look at timing, though wire sequence is correct and no reason to distrust it yet.

Once spark and timing are good we'll work on the gas if no start. We smell gas on the plugs, so know gas is getting there. The carb was professionally rebuilt by the PO last year, but I have a good spare carb to swap out to help diagnose issue there simply. Also will test the quality of gas by taking a sample from the Racor. Will also put a new filter on the Racor. If still no start will try new gas using an external tank.

That's the plan! Am I missing anything?