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Donzi Vol
05-28-2011, 02:39 AM
Ok, the boat has been running great until it randomly starting acting up today. We rebuilt the carb today, put it back on (I actually wasn't there for this part of it), it fired once, then hasn't fired again since.

Here are the details:
-Kill switch is in tact
-No wiring was touched or moved during the carb removal or replacement
-Most of the wiring is new, and all connections are good
-Coil is good (tried a replacement just to check)
-Electronic iginition conversion module in the distributor isn't the problem because I bought a new one today to try, and it didn't help.
-Motor is turning over fine, just no spark
-We have ignition power at the coil, but no spark coming out of it when cranking

This happened when I first brought the boat home nearly two years ago, but removing the points and replacing all of the wiring and distributor cap did the trick. It's been running great ever since.

Any ideas? We're baffled :confused:

Thanks in advance for the help!

silverghost
05-28-2011, 03:07 AM
You need to get out the multi-meter and start checking + voltages from your coil & disributor back to your key-switch, lanyard switch, fuses etc.
Trace your power from the engine back,
How is your rotor & distributor cap ?
Is the cap's spring loaded carbon contact still intact ?

Are you SURE it's the ignition and not that carb you guys just fooled with ?

MOP
05-28-2011, 06:44 AM
Borrow a pack from you checks so far the pack is suspect, another thing to check is the ground wire from the pack to the bottom of the distributor. If that ground is not making properly the pack will not fire.

Phil

Sweet little 16
05-28-2011, 07:12 AM
coil have an internal or external resistor?

joseph m. hahnl
05-28-2011, 09:25 AM
Alpha Drive??? shift interrupter out of adjustment.

http://www.sterndrives.com/switch.gif

Donzi Vol
05-28-2011, 10:20 AM
You need to get out the multi-meter and start checking + voltages from your coil & disributor back to your key-switch, lanyard switch, fuses etc.

Everything seems to have proper power. That was one of the first things I checked. I haven't taken any voltage readings, though.

Trace your power from the engine back,
How is your rotor & distributor cap ?

Both seem to be ok, but I might replace them just to be sure. A bad cap would certainly be a problem.

Is the cap's spring loaded carbon contact still intact ?

Not sure.

Are you SURE it's the ignition and not that carb you guys just fooled with ?

Yep, it's ignition. The carb is delivering fuel just fine, but no sparks past the coil.




Borrow a pack from you checks so far the pack is suspect, another thing to check is the ground wire from the pack to the bottom of the distributor. If that ground is not making properly the pack will not fire.

I actually woke up this morning thinking that it could be a ground issue. Where exactly might this ground be found?

Phil


coil have an internal or external resistor?

It's just a standard coil pack with nothing else in the loop, so my guess is that it's internal.




Alpha Drive??? shift interrupter out of adjustment.

http://www.sterndrives.com/switch.gif

Good thought, but it's a volvo drive. It will start any most any position.



Thanks for the thoughts, guys. I'll keep you posted.

MOP
05-28-2011, 10:42 AM
What?who's ignition are you running! I also assumed Merc. Phil

Donzi Vol
05-28-2011, 10:48 AM
What?who's ignition are you running! I also assumed Merc. Phil

Do what now? Maybe I should have mentioned that it's a Ford to Volvo package. Sorry.

MOP
05-28-2011, 10:51 AM
So you are running distributor and coil no pack? Or do you have after market?

Donzi Vol
05-28-2011, 12:06 PM
It's just a standard coil and a distributor.

MOP
05-28-2011, 12:40 PM
Ok thinking! New module, juice at the coil, also tried a coil. Hook your volt meter to the coil see if the voltage drops off when you try cranking it. You could have a bad coonection that will not carry much if any load.

mrfixxall
05-28-2011, 12:43 PM
run a hot wire from the battery straight to the + coil and try to fire..if it fires then your ignition switch or tether is open when in the crank position...


If you have spark at the coil and not to the sparkplugs then you have either a bad coil wire or a bad ignition rotor..

silverghost
05-28-2011, 02:23 PM
Could the spring loaded center round carbon contact assembly have fallen out of your distributor cap ?
It can happen~
If this is indeed the type of cap inside center contact you have on that old H/M Ford ?
Marine Mallory or Prest-o-lite ?

Check your high voltage center coil wire connectors & condition & your rotor also~~~as Fixx already had mentioned.

thescooter
05-28-2011, 03:08 PM
i always have a extra cap and rotor wires plugs in the boat in a nice dry place in a bag. i have used the extra 2 times in the last maybe 10 years to get out of a jam. i always save my old parts that worked for backup. not saying it is your problem but a good idea and a way to rule out what it is not.:bonk:
this also saves you from hitting yourself in the head.
nick thescooter

zelatore
05-28-2011, 07:56 PM
I think the first thing I'd check is does the coil fire at all. Sounds like you've tested that you have 12v to it, and you've replaced the ignition modual from your points convertion. If the coil will arc to ground when cranking it's almost certainly the rotor - a cheap and easy fix.

Heck, could be something as simple as a wet cap/rotor, though I doubt you were working on it in the rain.

Bobby D
05-29-2011, 09:15 AM
Sounds like thh same problem i had several years ago after converting to and igniter module. I had to figure out why the no spark problem happen again?
I have a copy of the 1972 Holman Moody owners manual for 302/351 Ford engines and after reviewing the wiring diagram I found that I did not have an ignition resistor to limit the current and I smoked the Pertronix ignition module.
What I did about it:
I ordered and installed a new PNX-1281 igniter module and a new ballast resistor.
I checked all the wiring again and the engine started right up as usual with no problems. Let it run for about 30 minutes and shut it down and looked everything over again and found no problems.

Donzi Vol
05-29-2011, 09:24 AM
I think the first thing I'd check is does the coil fire at all. Sounds like you've tested that you have 12v to it, and you've replaced the ignition modual from your points convertion. If the coil will arc to ground when cranking it's almost certainly the rotor - a cheap and easy fix.

Heck, could be something as simple as a wet cap/rotor, though I doubt you were working on it in the rain.

Well, a little update here. I talked my mechanic into going to his shop yesterday to help me out (and getting the boat out of lock and key so that I could work on it more). We unhooked the tach wire from the coil, and now we're getting spark from the coil to the distributor (did the arc test). Not sure if that was interfering or just a coincidence. Either way, we're getting spark from the coil, but the motor is still not firing. We changed the plugs, as they were covered in gasoline from all of the cranking and no firing in the last two days. Still not firing, though. We ran out of time, as he had to leave. However, he let me take the boat, which is at my office and ready for me to work on this afternoon.

I'm also leaning toward rotor or cap. At this point it has to be, since the spark is getting to the cap.

Could it still be the electronic ign sender? I guess it's possible that the replacement one that I picked up could have been bad.

Thanks again for all of the input!

MOP
05-29-2011, 10:15 AM
A bad tach will kill your spark!

hardcrab
05-29-2011, 10:19 AM
A bad tach will kill your spark!
Thats an eyeopener ! I never thought about that

thescooter
05-29-2011, 02:12 PM
now that thought about you problem.
i have a pair of HM 302 -Volvo 250 drives.
what you described happened to me once.
It was the ballast resistor on the distributor.
to check you by-pass it with a wire or screwdriver temporarily.

Donzi Vol
05-29-2011, 05:13 PM
Well I've messed around with it today by performing a number of tests, and we're still at 'spark into the dist, but not out'. I have a new cap and rotor on order and will pick them up from th auto parts store in the AM. If that doesn't do it, then back to square one...wherever that is.

Scooter, I'll give that a look. Not sure if I have an external resister, though. Would it be an obvious object that I couldn't have missed by being knee deep in the system the last 3 days?

Thanks

MOP
05-29-2011, 07:05 PM
Curious have you taken a hot wire right from the battery to the coil and tried it.

Donzi Vol
05-29-2011, 09:20 PM
Curious have you taken a hot wire right from the battery to the coil and tried it.

Yep. I did a jumper wire and put a booster on the battery just to make sure I had plenty of juice. Still no fire.

Sweet little 16
05-30-2011, 12:38 AM
does this look familar?? this would be somewhere on the bell housing??? the coil usually has a label for use with an external resistor or it has an internal resistor. the coil is a step up transformer and pumping up the input or boosting it up will pump up the output and fry things if they are not setup to take it. points may not be a performance upgrade but it is nice to be able to take a screwdriver and test things.

MOP
05-30-2011, 07:21 AM
Problem is he has juice if the resister was popped he would not have any.

BUIZILLA
05-30-2011, 07:55 AM
is it MSD or Mallory? or cheap automotive with aluminum terminals? you can ohm test both sides of the cap center pin for continuity

mrfixxall
05-30-2011, 01:56 PM
From what you described it sounds like the rotor burnt a hole in the center and is grounding out to the center of the distributor..pull the rotor and look where it mounts,,look for black hole of spark traces to ground..

Donzi Vol
05-30-2011, 05:00 PM
Ok, replaced the cap and rotor today, and we now have spark to the plugs! I could not get the motor to fire, but I'm pretty sure the culprit there were two drained batteries that would hardly turn the motor. I think I pretty well wore them out with all of the testing and cranking that I've done in the last two days.

I don't think it's getting the right amount of fuel, but that is to be expected after the carb rebuild. It just needs to be tuned in, I suppose. The batteries are charging tonight, and we'll see if she'll fire in the morning. I have a feeling she will, as usually spark+fuel+oxygen=fire.

I'll keep you posted. Thanks again for all of the help!

-David

silverghost
05-30-2011, 07:36 PM
:David:

Hope you finally found your ignition problem.
I suspected it might be a cap/center carbon contact, or rotor issue.

Re: Battery in discharged condition.
Be sure to get both your batteries on charge very quickly

If normal standard lead/acid batteries are left to sit in a deep discharged condition for very long ~
They my never fully re-charge to normal amp output cpacity; or a fully usable charged condition
It does not take very much deep discharge time to totally ruin a battery.

Get them both on charge today.