Bah...almost the perfect weekend - but the engine quit

[ndutton]

Oh no, this thread is turning down a dark alley like another one not too long ago.

Why not fix the @#$% problem instead of engineering around it?

[hanleyclifford]

Oh no, this thread is turning down a dark alley like another one not too long ago.

Why not fix the @#$% problem instead of engineering around it?

You're right Neil; we need to get a grip here before we get lost in space... er... the maze. I stand by my earlier recommendation - get the input voltage to that coil down to the minumum that will produce a viable spark.

[ndutton]

While adjusting the regulator with an eye on the coil you'd better keep the other eye on battery charging needs. At some point one affects the other and not favorably.

Gotta find the sweet spot.

[hanleyclifford]

While adjusting the regulator with an eye on the coil you'd better keep the other eye on battery charging needs. At some point one affects the other and not favorably.

Gotta find the sweet spot.

Exactly, and that is why a little experimentation with resistors is now in order. For Shawn's purposes, I think setting the regulator to 14.0 volts would be a good start. Then line up sufficient resistors to knock that down below 13.0 volts just ahead of coil+.

[ndutton]

Sorry Shawn, it feels like we're talking behind your back.

I don't agree with the need for experimentation. There are likely scores if not hundreds of A-4's with Pertronix (aka Moyer) electronic ignitions with Don's recommended 3 - 4 ohm coils that perform flawlessly year after year and I see no reason Shawn's shouldn't be the same. The experimentation and field testing is behind us.
edit: The above statement could not have been more wrong. Check out this thread, all of it.

If we can accept the foregoing it leaves few possibilities in Shawn's case. His input voltage might be a little high but it's not out of whack. There's an irony here - see last paragraph. And then sometimes with electrical components they just give up the ghost. They just do. Who hasn't taken a brand new light bulb out of it's package, screwed it in and poof, it's blown out?? I usually experience a 2 - 3% failure rate with brand new fluorescent lamps (usually those hecho en Mayheeco). It just happens.

Here's the irony. Shawn has an adjustable regulator which some swear by and yet it seems he's headed toward adjusting it virtually the same as a fixed output reg. This adjustable reg may have created more trouble than it solved.

[hanleyclifford]

While it is true there are hundreds of A4s out there with electronic ignition systems, what needs to be appreciated is that not all ignition systems are the same - even the ones with the same coils, distributors and alternators. Why? Because wiring differs from boat to boat, as does loads on the ignition circuit. For example, in my boat the ignition circuit also feeds the electric fuel pump and the salt water pump - both continuous loads. Can there be any doubt that my effective voltage to coil+ is going to be much less than alternator output voltage? Shawn, on the other hand, with a super clean (no good deed ever goes unpunished) wiring set up and a direct alternator to coil+ would be delivering much more voltage to the coil than I do even if we had the same alternator output voltage. The resistor is the means of "correcting" voltage to a component that is sensitive. This procedure will be unique to every vessel. Next time I run my engine I will read off some voltages and report back to the forum.

[ndutton]

Respectfully, I would think your voltage at the coil would be a function of wire size and length. A properly designed system should be sized according to the circuit length and load and hold the voltage to a prescribed maximum voltage drop (I prefer 3%). That's why we have ampacity tables and voltage drop calculations.

[hanleyclifford]

Respectfully, I would think your voltage at the coil would be a function of wire size and length. A properly designed system should be sized according to the circuit length and load to hold the voltage to a prescribed maximum voltage drop (I prefer 3%). That's why we have ampacity tables and voltage drop calculations.

Agreed, and in this respect I am a big violator. From the 100 amp fuse panel I run #8 to the ignition panel about 3 feet, thence #8 to the OPSS about 5 feet, thence a pair of #14s to the ignition buss bar about 4 feet, thence #14s to coil+, salt water pump, and fuel pump. I have never thought much about this matter but now that we are discussing it I am going to take measurements and report back to the forum. Although my garden variety automotive coil has no external resistor (marked as internally resisted) it never gets too hot to touch.

[ndutton]

I was thinking of modifying my previous post when yours popped up so I'll say it here instead.

Connected load could be a factor at idle or an RPM too low for the alternator to kick in.

I'll avoid commenting on fusing with your system as described, save it for another time.

[hanleyclifford]

My alternator is running at 3 times engine speed so I actually have the reverse problem: if I don't take all batteries off line except a fully charged reserve when starting, the alternator tries to bog the engine before it warms up. As to fusing, I keep an in line fuse just before the fuel pump but I do have some work to do in this area to get up to standards.

[sastanley]

Gentlemen, Thanks for continuing the discussion.

Just to clarify Hanley's comment about my 'super-clean wiring' & then his detailed description of his circuit:

One thing pretty high on on my "boat list" which has not been done yet, is replacing the wiring to the ignition switch & instrument panel up in the cockpit. The 1977 wiring is still feeding the 'ignition bus bar', & could possibly be having some sort of failure after extended running time. This was brought to the front of my little brain again this weekend when I was installing the new coils & I realized this is still in the mix. I think I want to do this before I consider adding in any new loads or wiring to accommodate electric FWC, which is also in the works. However, this weekend, I did not have any engine failures at 20 minutes like I was able to re-create over the couple evenings of testing last week. I do not think the ignition circuit is a factor at this point..but if I follow Neil's mantra?? of 'aggressive replacement', it should be dealt with to eliminate it as a possible culprit.

As many of us know (and well documented here by Don Moyer) the Catalina 30 wiring harness is problematic. However, I have removed the ammeter, & when I replaced it with a voltmeter, I did either replace many of the connectors behind the instrument panel, or at least inspected them for good contact, and I also cleaned and lubricated the two plugs in the middle with electrical contact cleaner.

By the way - after Hanley's comments last week about my wiring scheme, I did re-wire the bus bar so that the purple from the ignition switch goes directly to the bus bar, and now I feed the coil & all accessories from the 12v+ bus bar (which is probably how I should have done it in the first place, isn't that the purpose of the bus bar?!) The only wires now on the coil studs are the (+) & (-) to the Pertronix EI & the green wire to feed the tachometer. This was also modified in the event I had more failures..I could switch coils by simply changing two wires (& the swapping over large secondary wire from the distributor) & be up and running again in a matter of seconds instead of minutes. I also have separate (+) lines from the bus bar to each coil, so that I can keep the resistor feeding the proper coil. This also speeds swap over time, as I can use a screwdriver at the bus bar to disconnect one & connect the other, instead of a wrench and little tiny nuts & star washers, etc. on top of the coil. Now that I have two coil brackets, what this also allows me to do is have two coils in the engine room with easy access to all the wiring, and I can choose to do a little experimenting if I want (i.e. put the old coil back in, etc.)

So, not everything in the circuit has been replaced...yet.

Here is where (I think) we stand:

I plan to keep the adjustable regulator & fine tune it to 14.1v at the batteries.

Just as a refresher, the purpose of the adjustable regulator is to compensate for the passive Hehr Powerline diode-based battery charging isolator that I have installed. The stock regulator (at 13.8v) only provides 13.1v to the batteries thru the isolator...I think we all agree that is not enough. On the other hand, me feeding it 15v+ is too much..

The ignition circuit (& all 12v systems on the boat) are fed thru the isolator, so if I adjust the regulator until I have 14.1v at the batteries at cruise RPM (which I didn't until this weekend), I should be no different than anyone else & I can continue on with other boat projects..

Bill, I was not serious about the coil cooler. I've already remotely mounted them in the engine room & off the motor. Maybe Jim was..

Did I miss anything?

[ndutton]

As has been demonstrated repeatedly, I'm an old skool sort. I use 40 year old battery switch designs because I like them even after I was enlightened by Rigs about the 4 post internally combining Blue Seas switches, don't have any new fangled charging relays, adjustable regulators, isolators, 3 stage charging systems or fancy monitors. My system is basic, manually switched, charges to preset voltages. Very basic and very boring.

But I also don't have to compensate for voltage losses through isolators or charging relays and deal with the domino effect on other systems. Maybe I'm ignorant as to the benefits of such technology but sometimes ignorance is bliss. I'll keep on managing my batteries with basic battery switches and fixed point internal regulators. My lead-acid batteries are 6 years old and still going strong. Let's hear it for the dinosaurs!

And for the record, I struggled with the move to electronic ignition. In asking for opinions prior to the change I pointed out to the forum that there were repeated postings of EI failures only to be rescued by reinstalling the old points. In fact it's universally recommended around here to carry the old points 'just in case.' I made the 'upgrade' on the recommendation of others, still carry the points. So far so good.

[hanleyclifford]

All this time I was thinking of Neil as a fellow Neanderthal when I should have been thinking dinosaur. That'll learn me.

[jpian0923]

I was sort of serious in the sense that I wanted to hear good reasons why cooling the coil is not a good idea. I know it doesn't address why the coil is getting hot.

I'm not a mechanic, electrician or a very experienced Afourian so I'm trying to learn as much as I can in this forum.

I know I throw out crazy ideas every once in a while but I think they are food for thought, if not at all constructive. I'm a thinker.

[hanleyclifford]

Your idea of coil cooling is not at all out of line - Google "performance coils" and check out the Mallory 30441 complete with cooling fins.