converting a vintage ob to electronic ignition

[nwcove]

have been searching threads, and can only find one where the op was going to try it and post back, but the thread ended there. my 58 rude 10 hp has pitting on the points cam, so im considering switching over? anyone have any experiences....good or bad going this route?

 

[HighTrim]

Re: converting a vintage ob to electronic ignition

Never done it myself but know a couple guys that used the ATOMS with success. One day I will when I have time just to say Ive tried it. I have a motor with a slightly worn upper bearing that would run better with electronic ignition.

Been to this site yet?

Banta Saw - Small Engine Parts and Accessories - Home Page

 

[JB]

Re: converting a vintage ob to electronic ignition

I would just replace the cam, nwcove. I have always found magnetos far more reliable and far more fixable than electronic gadgets. . .and that from an old school BSEE. . .

 

[nwcove]

Re: converting a vintage ob to electronic ignition

Never done it myself but know a couple guys that used the ATOMS with success. One day I will when I have time just to say Ive tried it. I have a motor with a slightly worn upper bearing that would run better with electronic ignition.

Been to this site yet?

Banta Saw - Small Engine Parts and Accessories - Home Page

thanks Chris, i have been to the banta site after it was mentioned awhile back in another thread, and thought it could be an interesting experiment..... now i actually have the order form filled out and am kinda ready to pull the trigger. but just a bit sceptical as the mfg co has been out of business for quite awhile.

 

[nwcove]

Re: converting a vintage ob to electronic ignition

I would just replace the cam, nwcove. I have always found magnetos far more reliable and far more fixable than electronic gadgets. . .and that from an old school BSEE. . .

i fully agree JB, but after doing some looking and cost comparison, if those gizmos actually work, im a few bucks on the good side.....if not i have some useless doo-dads laying around.

 

[nwcove]

Re: converting a vintage ob to electronic ignition



ignition conversion is done after some confusion with the ground wire. ( reverse polarity ignition ) wired up one coil as per the instructions with no spark, then reversed the wires as per the trouble shooting guide and have spark, but on a side note...the modules are not supposed to produce spark at very low rpms " quote "electronic spark module has anti-kick feature and will not spark at low speed rpm". this is not true, as i can get spark by rotating the flywheel by hand.
the motor still needs work to be a runner, but i will continue this thread as it progresses. ( anyone know where the heck i put the new impeller???!!!! lol)

 

[HighTrim]

Re: converting a vintage ob to electronic ignition

Cool let us know how she runs!

The impeller is under the bench beside that points spring that went flying off

 

[RogersJetboat454]

Re: converting a vintage ob to electronic ignition

Watching this thread with interest.

While I can appreciate the simplicity of a standard old school magneto, solid state ignitions are reliable, and very well proven.

Good luck! :encouragement:

 

[nwcove]

Re: converting a vintage ob to electronic ignition

put it in the tank earlier.....mostly assembled ( no air box and being gravity fed its fuel). 4 pulls and it fired up. a few sneezes and some tweaking of the ls needle and it runs quite well. it doesnt idle as smooth as my smaller motors, but the sync is way off.....cam touches roller about an inch late. im amazed at how little smoke this motor produces, im using 16:1 fuel. idling for 15 mins and you could barely see any smoke, but a slight increase in rpms would produce a puff, then barely none again. not sure if thats due to the modules " multiple fire" per ignition cycle or if the motor just doesnt smoke like my others.
still have to finish putting the motor completely together and converting to fuel pump, but so far so good. and if this experiment goes south, there were no mods done to the mag plate, so it can easily be put back to original.

 

[Willyclay]

Re: converting a vintage ob to electronic ignition

Great news! Thanks for the update.

 

[cbercaw]

Re: converting a vintage ob to electronic ignition

Pretty cool, Good job

 

[Cap'n Chaos]

Re: converting a vintage ob to electronic ignition

Hey NW, which module did you use? I can't tell from the photograph.

Apparently that one has some sort of sensor in it to detect the magnet passing by?

 

[nwcove]

Re: converting a vintage ob to electronic ignition

Hey NW, which module did you use? I can't tell from the photograph.

Apparently that one has some sort of sensor in it to detect the magnet passing by?

seems as tho the magic that goes on in the module is related to peak voltage at the coil (s)( i.e. you can mount the modules externally), and somehow the peak voltage just happens to be at the ideal time to fire the plug. its all voodoo to me....but it seems to work well. ( left the motor in the barrel over night, and it fired up first pull this morning)

the modules are color coded. as you can see i used the red module that works with motors that have the movable mag plate.....but not motors that use four magnets in the flywheel to charge a battery.

 

[RogersJetboat454]

Re: converting a vintage ob to electronic ignition

seems as tho the magic that goes on in the module is related to peak voltage at the coil (s)( i.e. you can mount the modules externally), and somehow the peak voltage just happens to be at the ideal time to fire the plug. its all voodoo to me....but it seems to work well. ( left the motor in the barrel over night, and it fired up first pull this morning)

If you think about it, Briggs & Stratton has had pretty much the same system (Magnetron Ignition) since the early 80's. Solid state, all housed in the coil. Popular swap for people with the old points style Briggs is to buy the Magnetron coil (abandoning the points all together). It installs the same way as the old style coil.

I don't know how they work, but maybe it's like you say, the guts of the module is looking for peak voltage. They are certainly well proven, and reliable.

 

[nwcove]

Re: converting a vintage ob to electronic ignition



well i "think" i have this one buttoned up. ( other than fuel line clamps). the modules seem to work well, fuel pump conversion went well but the pump had to be tilted a bit to clear a casting and a vibration rubber on the cowl.
im into this motor for more than i thought i would be as it cost about $150 to totally overhaul the water pump....new impeller, impeller housing,impeller plate, grommet and ds oring. but at $350 total cost( motor and parts) for what seems to be a nice runner, its not all bad when you see what the asking price is for a 1980's 9.9 that ran " the last time i used it" !
hopefully i can get it out of the barrel and on the water for a real test on the weekend!!
( and yes .....the nasty looking tee on the fuel pump pulse nipple will get changed to an elbow....as soon as i can find one that has a compression fitting at both ends! lol)

 

[Cap'n Chaos]

Re: converting a vintage ob to electronic ignition

Neat looking setup nw, that's got to be the best positioning of a fuel pump I have seen...you don't have to worry with clearance issues the way you have it mounted... is that one of the Mikuni fuel pumps? Can you take a photo of the side of the motor where the fuel pump would normally be? I am curious to see how you have it set up.

This thread has really opened my eyes, thank you.

If I ever get up your way I'll buy you a cup of that Tim Horton's coffee I hear the Canadian truck drivers raving about.

 

[nwcove]

Re: converting a vintage ob to electronic ignition

on the 10hp motors , the fuel pump location of choice is under the carb. hightrim posted a pic of the rear mount option which looked good to me!! clearance is there , but its tight with the pump bracket i made. in pic 3 you can see where the bypass cover was drilled and tapped to take the fitting for the pulse to the pump. that is basically the location of a factory pump on a more modern motor.

 

[Cap'n Chaos]

Re: converting a vintage ob to electronic ignition

So is that a Mikuni fuel pump... those look like brass compression fittings you could find in any hardware store plumbing aisle.

 

[nwcove]

Re: converting a vintage ob to electronic ignition

So is that a Mikuni fuel pump... those look like brass compression fittings you could find in any hardware store plumbing aisle.

it is a mikuni rectangular single line pump(rebuildable). and yep.....those are just brass compression fittings that can be found at most any hardware store. as you can see from the pic, i couldnt find a 90deg elbow with compression fittings on both ends for the pulse inlet, so i had to plug a tee. also notice the pulse line is not the soft fuel line, i use plastic 1/4" chemical feed line so there is no chance of it collapsing under vacuum .

heres pics of a 57 5.5 ( first pic)with the same pump side mounted and plumbed with 1/4" copper tubing, no clearance issues. second pic is a 58 7.5 with the side mount done using a briggs and stratton/mikuni pump....lotsa clearance with that style pump, but its not rebuildable.

(note: the cable ties shown in the pics are just cable ties that i used for testing, they have long since been changed to proper fuel line ties....brp # 320107)

 

[64osby]

Re: converting a vintage ob to electronic ignition

nwc - very nice work on the ignition. Looking for the updates from on the water.

What's the parts# on the Mikuni rebuildable pump?