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AQ125A Pertonix 2842 installation question

T

Texan

New member
After reading up on the many believers in the Pertronix ignition, I am installing one on my AQ125A currently. I believe I understand the wiring correctly, but could use a confirmation as a sanity check. My current setup:

Bosch coil, 3.7 ohms aross terminals 1 and 15. I believe 1 is the negative and 15 is the positive terminal. Attached to terminal 15 is a single purple wire. This wire is energized with 12V when key is on. Attached to terminal 1 are a purple wire and a grey wire. I believe the grey wire goes to the tach and the purple wire goes to the distributor. These two wires are bundled together in a single spade connector.

At the distributor there is a capacitor connected to a purple wire that originally also connected to the points before they were replaced. I measure 0 ohms between the purple wire at the distributor and the purple/grey bundle at the coil.

So, I need to connect the red wire from the Pertronix kit to the 15 terminal at the coil. This will mean there will be two wires at the 15(+) coil terminal - the Pertronix and the 12V key on purple wire. I will connect the black wire from the Pertronix to the 1(-) terminal on the coil. This will mean there will still be two wires at the 1 terminal - the grey (tach) wire and the Pertronix wire.

Hopefully this is clear. Afterwards I will be setting the timing. The procedure I have gleaned is:

1. Setup muffs on the water intake, introduce water
2. Start engine, allow to warm up
3. Attach timing strobe to #1 plug (closest to bow)
4. Set timing (should look directly down at crank to view timing marks properly)

Here is where I have a question. From my manual, for 87 octane, I show
0-750 rpm ("basic timing") should be 4 degrees btdc
4000 rpm ("stroboscopic timing") should be 29 degrees btdc

Does this mean I am to set the timing at 4000 rpm or 750 rpm or does it matter?

Also, are there any tricks to running the engine with the muffs? I believe all that is needed is a strong exit stream from the rear of the drive to indicate sufficient cooling. Obviously I will be monitoring the coolant temperature.

Thanks to anyone who can help and to those whose previous posts I read.

Chris
 
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So, update...

I wired the Pertronix unit up as described above and the engine would not run - cranked and backfired, tried to run but sputtered out. I quickly ran out of daylight but observed the Pertronix unit red lead was seeing about 10.7-11V. I disconnected the lead from the coil and attached directly to +12V at the battery, no change.

Some questions:

1. The capacitor that was originally in-line with the points and the negative side of the coil - I assume that should remain installed with the Pertronix ignition? I tried with and without to no avail.

2. The alternator on the boat appears to have an excitor wire connected (purple wire with a resistor). It is a Paris-Rhone unit. I get the expected 75 ohms between the purple lead at the alternator and the purple lead at the + coil terminal. For reference, this purple lead at the + coil is the 12V key-on mentioned earlier. My question is, shouldn't there be a third 12V key-on power lead to the + coil? I seem to recall reading in other posts that a non-self exciting alternator setup would normaly have two wires at the positive coil, with the third added for the Pertronix unit. Strange though, as before the ignitor install there was only the single purple wire at the positive terminal.

I didn't have a second person handy to check the spark at the coil, so will do that tomorrow. Also charging battery to full, was slightly drained.

The boat ran fine about three weeks ago with the points installed and no other changes have been made in that time.

Based on my experience with automotive engines, I would say this is a classic case of out of synch ignition timing. So, with that in mind... I double checked the magnetic ring and it is flush at the bottom with the pickup. The cap appears to be fine and I cleaned off the slight oxidation on the rotor. It appears the magnetic ring will fit on the distributor shaft 4 ways (90 degree rotations about the shaft). I think these 4 alignments should be equilvalent. Clearly, the ring cannot be installed upside down. I have verified the air gap using the plastic feeler provided.

I figure I am missing something simple but it escapes me at the moment.
 
Hi,

1) The wiring is simple: red to the positive side of the coil, and black to the negative.

2) You need to remove the capacitor from the distributor. This point is made clear in the installation instructions (have you read them?).

3) Some installations take the exciter wire from the + side of the coil, and others directly from the ignition switch. Either way works.

4) The magnetic sleeve works on either of the 4 possible installation positions.

5) Read and follow the instructions, they are quite simple.

http://www.pertronix.com/support/manuals/pdf/ignitor12vneg.pdf

6) Check for spark. If you have spark, check that the spark plug leads go to the right spark plug (check firing order). If they do, you will probably have to re-adjust the ignition timing.

7) Here are some troubleshooting tips.

http://www.pertronix.com/support/tips/default.aspx
 
Thanks El, that's what is bugging me - this is about as simple an installation as could be imagined.... I did read the instructions and troubleshooting pages. It wasn't clear to me that what Pertonix calls a condenser referred to the capacitor though. This is a boat that is new to me, and the previous owner was not always up to par on repairs, often things are modified in unusual ways. Firing order is correct, I am suspecting the timing may be way off. Perhaps the previous owner adjusted the timing rather than the points dwell angle? Anyway, I will be able to investigate further now that there is some light outside.
 
So, in my typical fashion, I was making a simple problem complicated. Turns out the distributor was way out of time. I moved it to where I thought it should be and the boat fired right up. Now to dig out the old timing light and finish the job. I also am onl getting 11V through the coil, so I will probably wire the Pertronix unit directly to a 12V switched source.

El, thanks for your help.
 
You are welcome.

One more thing. You need to wire the Pertronix unit to the coil, so that when you turn the ignition key off there is no power going to it. Otherwise, you will fry it in no time.

If you are not getting 12V to the coil, either your batteries are low or your wiring needs to be replaced; but 11V is still an OK voltage.
 
Thanks again, I will likely leave it alone unless there are performance issues on the water. 1 volt is kind of a lot of voltage drop, but I do need to fully charge the battery before jumping to conclusions. Looking forward to improved boating experience with a solid ignition!
 
Well, put me down as another satisfied Pertronix covert. Everything was great, starting, idling, etc. That is, untill the timing belt slipped a tooth while on the water and died. After moving the distributor ~15 degrees I was able to get it back to dock and home. Time for a new belt, tensioner, impeller, etc!

Chris
 
HaHa, was great up till then. Of course, we couldn't die out in the middle of the lake, we were in a rocky cove! My wife, bless her, kept the boat from running aground while I got us back up and running. Other than the timing belt, tensioner, drive belt and impeller, are there any other recommended items while I'm in there? Just got my Seloc manual today, was thinking of pulling the valve covers and setting the valve lash. Didn't get a chance to read the manual yet, but I've done it a bunch on old Chevy small blocks. Figured I'd also service all the fluids (engine oil and coolant, leg oil, grease fittings, etc. I saw an old thread regarding recommended lubricants, will reference that when making my purchases. Plus new plugs and general clean up. (Sandblast valve cover and paint, etc, etc.)

Glad I like to tinker with older equipment!
 
Make sure the timing gears are not pitted. If they are, consider getting another set; automotive is fine, and if you buy it at an auto wrecker you can save some money. A pitted/corroded set of gears will eat your new timing belt in no time.
 
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