no spark

oldboat1

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I'm trying to get a 9.9 autoelectric running (mod. 95HA) -- getting no spark. The coils look OK, as do the points (which I regapped just to be sure). The condenser wires had some wire showing where the flywheel had apparently come in contact -- thought that might be the problem, and tucked them out of the way. I still have no spark, though.<br /><br />I don't know how to test coils. I sort of figured I would find that the cases were cracked as on some OMCs I've worked on, but they look fine.<br /><br />To further confuse issues, I pulled the flywheel on a 6hp powerhead I have for parts -- same magneto, and also no spark. I found the same thing (coils and points look fine). Again, there was some abrasion of the condenser wire. <br /><br />What is the likely problem? I don't have known good coils to swap out, and these are apparently a little hard to find. Would a bad condenser cause loss of spark? (or a bad condenser wire? I checked for continuity, and it checked out OK.) Is the problem the coils, even though they look fine (actually, all four of them)?<br /><br /> Thanks in advance for any ideas.<br /><br /> Curt
 

eurolarva

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Re: no spark

When you tested for spark did you ground the plug? If not you will not get a spark. Wrap a wire around the threads of the spark plug and tie the wire to something metal on the motor.
 

oldboat1

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Re: no spark

Thanks. I use a plug that was fabricated for testing (has a clip for grounding to the engine). In testing the 9.9, I also made sure the plug wire ends were in contact with the plug, thinking that might be the problem.<br /><br />It does seem unlikely, though, that all four coils are bad in both powerheads -- particularly since they look good. I think I will try to test for spark without my handy-dandy test plug. That didn't occur to me until your post.
 

scotiany

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Re: no spark

I think you need an electrical schematic of your ignition system. I don't have one for your model. If I did , I'd scan it and email it to you. Maybe someone in the forum has one. I agree that it doesn't seem likely that 4 coils would be bad . On mine (55hp magneto ign.) there is a wire from one of the condensers to the terminal block of the wiring harness. It looks to be a ground . Not trying to be a wiseguy but, did you test with the flywheel installed?
 

oldboat1

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Re: no spark

I have the schematic, and the hookup looked right when I checked it out (don't remember offhand if this model has the ground to which you refer). Some models apparently have a ground to the coil housing, and some ground to the one of the screws holding the points, but that was the only question I had. Both wires from the coil(s) go to ground -- one at the breaker point contact, and one to the magneto plate. Tonight I checked my tester plug in a working engine, and it fired the way it should -- kind of hoped the test plug was the problem, but it isn't.<br /><br />Everything was back together to test (kind of a pain with the Autoelectric).
 

boatsmitty

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Re: no spark

I had a bad flywheel magnet in my motor w/o spark, replaced it with used flywheel.
 

oldboat1

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Re: no spark

I'm wondering about the flywheel magnet too, as I can't seem to come up with another solution. I checked out the keyswitch (two ground wires come from the magneto -- think it grounds both sets of points to prevent spark unless the key is in the run position). The keyswitch checks out OK, which isn't surprising as the starter works fine. <br /><br />I wonder if the flywheel magnet can be remagnetized. It seems to me I ran into a mechanic some time ago who had a way of doing that. I would try switching out flywheels, but the only other one I have also belongs to a motor that isn't producing spark (would switch out the coils too, if the other motor was working).
 

OBJ

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Re: no spark

Hi oldboat...not really a Chrysler wrench but most ignition systems work the same way. Don't know if the engine is "new" to you or not so I'll go on the assumption the engine was working.<br /><br />One set of points or one coil going out seems normal but both at the same time is unreasonable unless of some major upset like overheat.<br /><br />It would have to be something common to both cylinder ignitions. The only thing that comes to mind is the kill circuit. Look on your schematic and see if you can locate the probably black wire that would ground out the ignition system to stop the motor probably through the key switch. Disconnect that wire and then see if you have spark.<br /><br />This is just a shot here but who knows?
 

oldboat1

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Re: no spark

Thanks, OBJ. I'm thinking it must be something like that too. This is one of those AutoElectric models with the starter on top of the flywheel. I picked it up last summer, mostly for parts for a Chrysler Sailor model I use -- but decided it's complete and looks like it should be a runner. After some tinkering, I think I have it ready to go except for the ignition mystery. <br /><br />There is a ground from the magneto to the block, and two ground wires that go to the keyswitch. The keyswitch checks out (continuity between the ground wire posts only with the key in the run or start position). I will disconnect them like you suggest, and see if that takes care of the problem. It just occurred to me too that I should probably check to see if either or both keyswitch posts are grounded when the key is in the run position -- would check continuity from each of the posts to the block and see if the light goes on. I'm thinking there should be no ground at either of those posts with the key in the run position (?) <br /><br />It's possible that somebody replaced the points and didn't rewire correctly, although I haven't picked that up yet -- looks correct by the wiring diagram and the other engine/magneto I have. (The working motor I have is a little different, with the coils mounted on the block rather than under the flywheel.)
 

oldboat1

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Re: no spark

need to check out the keyswitch ground wires again. Contrary to what I said above, I think the testor light was on only when the switch was in the off position (which would be appropriate, I think -- engine would be prevented from starting with the key in the off position). Now that I think about it, though, it seems both the ground wires to the keyswitch would always be grounded to the block through the switch housing -- or maybe that's the clue: If one or both are indeed grounded to the block, the poles at the keyswitch are the problem because they are not insulated from the body of the switch -- and the keyswitch is the problem.<br /><br />makes my head hurt....
 

OBJ

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Re: no spark

Welllllll. About this time I'd start pulling components and start checking them individually. Apparently the motor has set a while.<br /><br />Maybe one more thing. Can you disconnect the wire harness from the motor? This would completely isolate the engine from the key switch. If you can, disconnect the harness and try pulling the rope starter (if equipped) and look for spark.<br /><br />And do look for any wires that may be on corroded posts or are maybe bare. You've probably already done this.
 

OBJ

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Re: no spark

Oldboat....you want I should bring in the cavalry?
 

oldboat1

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Re: no spark

Thanks, OBJ -- need something more like the whole 3rd Army.<br /><br />I've gone through the connections, although there is always the one that gets missed. I think the harness is probably in pretty good order because the starter works well. As you suggest, I need to pull off the electricals -- just installed a rewind starter (was missing)and have it working, so I can now check the spark without the electronics attached.<br /><br />I'm kind of back to the original dilemma -- can't bench check the coils as that is beyond me, and new ones are a little more than I want to invest (about $85 each). Additionally, I'm just not ready to believe yet that it's the coils.<br /><br />I'll check the wiring of the points and coils again to see if something is installed incorrectly. If I can't find the problem, I think I'll finish detailing the motor so it's at least a nice-looking anchor, for now -- then see if I can come up with a parts motor with a working magneto, and switch out known-working parts. It might be the flywheel magnet as one of the other listers suggested.<br /><br />must be something simple that I'm flat out missing.....
 

OBJ

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Re: no spark

I got a call out for the Cavalry. :D
 

scotiany

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Re: no spark

Don't know if this will help but, in my manual from Chrysler 35-55 hp it says the DC Resistance of the primary windings should be .6 ohms and the DC resistance of the secondary windings should be 5900 ohms. This is for the magneto coil only. The battery and CD coils have different readings.
 

oldboat1

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Re: no spark

Thanks, Scotiany. That could help. They are magneto coils, I'm sure. There are two red wires, one from the top part of the coil and one from the bottom. Both go to ground -- one on the plate, and one at the breaker point. The other wire is the plug wire.<br /><br />I have a multi-testor, but I really don't know how to check the resistance (and would like to learn). Would I unhook the red wires, and touch the black test probe to one, and the red probe to the other? Or maybe do I touch the red probe to one of the wires, and the black probe to a ground? For the plug wire, I would only have access to the plug end -- maybe would use the red probe at the plug end, and the black probe to ground? (guess one of the red wires, or both, would have to be reattached to their ground connections first)<br /><br />and anything you could tell me about the proper testor setting would be helpful too....<br /><br />I'm obviously out of my depth here.<br /><br />By the way, I checked the flywheel magnet and it seems pretty strong -- holds a screwdriver firmly.
 

scotiany

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Re: no spark

Send an email to scotiany12302@yahoo.com and I'll send you what I can find about testing coils. If you can send a small pic of your coil. I've got a 20hp assy I have no use for.
 

oldboat1

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Re: no spark

will do, Scotiany. I'll take a pic of the magneto assembly tonight and email it to you. Chances are, the coils are the same on the 20hp, but will see. The coils have the same part numbers as those on a Chrysler/Sea King assembly I wanted to use for parts, so they might be the same for a lot of early 70's motors. (Can't tell at this point whether the Sea King coils are good, because I'm not able to get spark with that motor either.)<br /><br />Thanks....
 

OBJ

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Re: no spark

HYI oldboat....95HA, HB, HD....from 1970 to 73'.<br /><br />Looked at some wiring diagrams at the shop but can't come up with anything other than testing individual components. Still think it's something common. But could be both sets of points and condensers are bad.<br /><br />You can test the condensers with an ohm meter if ya' got one. Set it to high ohms, meter ground to condenser case and meter "+" to condenser lead. The meter should go up and then drift back down to "0". If it don't, condenser is bad.<br /><br />I'll check in later. Gotta get ready for work :(
 
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