Bayliner Ballet

Later launch date

After 12 years it seems like we get around to taking the boat out later and later. This year it wasn't until early August before our schedules aligned and it was time to fire up the boat. For the first time it didn't fire up.

1986 Bayliner Capri 2.3

Troubleshooting ended with the coil being identified as the culprit. I headed to the local farm store for a 12V. coil where I learned that there are two types of coil: internal resistor and external resistor. Which do I need? The old coil doesn't say. The shop manual doesn't say. The reference guide lists both for the application. They only have one type in stock so I buy it (suspending my doubts). It's only $10.00 so what the heck.

I put it in and the boat fires right up. I get it on the lake and open it up. It runs like a top - until about half way across the bay when it coughs and sputters and then quits. So there I sit - dead in the water. After about 1/2 hour I flag down a passing boat and he tows me towards shore.  As we're going I try the engine and it fires. I drop the tow, thank the guy, and head off under my own power. About a minute later and a few hundred feet from the dock it sputters and dies again. I flag down a second boat and finally get to shore.

The coil is easy to remove so I do so and after some research, I test it with an ohm meter.  The

New coil installed (w internal resistor)

Primary (two posts on either side of the center) and it reads open. I test the Secondary (big connection in the center) to the primary. The "+" side is open and the "-" side has some resistance.

So I have burned up this coil.

This time I head to a local auto parts store - where I think they'll be able to look up this exact engine (Volvo Penta AQ131 140 hp 4-cylinder) and tell me what coil to get. Their book lists both types; resistor and non-resistor.

The old coil has a number stamped on the bottom that we find in one of their cross reference guides as having NO internal resistor. When I get back to the boat I search for an external resistor in and around the engine compartment and up under the dash. These are big ceramic things that should be easy to spot. I can find nothing.  This new coil cost $50.00 so I was a little hesitant fry it as well.

I measured resistances on the old coil and the new. They are as follows:

Old (yes, I know these resistances may be off a little because the coil doesn't work anymore):

Pri. 2.7-3.2ohm.
Sec. 7.6 - 9.9 kohm.

New coil w/o internal resistor because book said that was what old Bosh was.

Pri. 1.2 ohm
Sec. 7.2-9.8 K ohm. 

Old coil

These didn't seem to match so I took the coil back and asked for the other one (the one with the internal resistor) It also bothered me that I'd just burned up a coil that didn't have internal resistor and I could find no evidence of an external resistor in the circuit.

New coil w/ internal resistor

Pri. 3.4 ohm.
Sec. 7.2 - 9.8 Kohm.

This was much closer to the readings of the old coil so I put it in and launched the boat. It runs like a top.

Good reference

After searching a dozen or so Google hits, the reference I found on-line that finally decided this for me was the final comment in this forum link [Click here]. This is the boat repair forum on MarineEngine.com.