Odd starting quirk

[SFBayLarry]

I've been dealing with a starting problem with my A-4 for the past 6 months or so. Its a 1978 Catalina 27 with the original motor.

At first the starter was not engaging (clicking), but after having the starter re-built, and cleaning up all the cable contacts, it now engages and cranks nicely if the batteries are charged up.

However, the engine will only start up when I turn the ignition switch from start to run. In other words... its cranking over, but doesn't fire until I turn the key back from the start position to the run position. Once it starts, it runs fine. Could it somehow be getting enough current to run the starter, but not enough to create spark until the starter is turned off?

What are your thoughts? Coil?? Ignition switch?? (or its connections?)

Larry

[msauntry]

Sounds like yet another A4 owner is about to rewire their engine

That's a weird one. Guessing... but it could be a start switch going bad. Electrical gremlins are tricky. Give everything a once over and snug down connectors and check for corrosion on the switch. How confident are you that your engine is wired properly? Mine was all wrong when I got the boat, yet it ran so I didn't know any better until some things I remembered from this forum started clicking.

Where does the coil get its positive power from? Direct to starter switch or somewhere off the starter solenoid?

[JimG]

My 66 Chevy pickup did that, and it was the wire that bypasses the ballast resistor when starting that was missing. I don't think the stock A4 has a ballast resistor, but someone might have put an automotive coil in? Otherwise, it's probably the starter switch.

[SFBayLarry]

Thanks for the tips on the quirky start. Looks like I have work to do this weekend.

Larry

[msauntry]

As a reference (following path of 12v positive), here's what's on my boat.

Ignition switch to a common positive bus that powers the guages and blower and then to another bus in the engine compartment that powers:
1. hour meter
2. oil pressure switch (which in turn powers the elec. fuel pump)
3. coil
4. temp sender
5. oil pressure sender

You probably don't have buses, but your IGN and coil terminals are probably serving this funtion with multiple wire leads.

{{Some notes: I used two buses since it avoids having a bunch of electrical fittings stacked on the coil positive terminal. I also have a 4 way Cole-Hersee start switch which replaced my old key ignition and separate start button. It is common at West Marine.
It allows me to combine IGN and ST in one compononent as well as provide an ACC (accesory) switch which I used for my blower.
The 4 positions are: ACC-OFF-IGN-ST.}}

Does your coil positive have a bunch of electrical terminals attached to it?

Does your starter solenoid have anything other than the ignition START wire going to the S terminal and a large battery cable?

If you have a multimeter or ohmmetter, you can measure the coil resistance. 4 Ohms jumps to my mind, but double check that. A ballast resistor is a small cylindrical device that piggybacks on the coil and is hooked to one of it's terminals.

Let us know what you find.

[SFBayLarry]

Well, thanks for all the suggestions. Coil tested ok.

I finally took the batteries home where it was easier to test how they were holding a charge. And lo and behold, one of 'em was not taking a full charge & not holding its charge.

So I installed a new battery for the starting circuit. What a difference! Cranks and starts easily.

With her starting issues solved, I was able to get her over to the yard for a bottom job (it had been 6 years!), and am now eager for summer sailing on the SF Bay.

Larry