B&S 11hp engine question

[handirifle]

So, a friend of a friend, has this old Heald Hauler that they got NOT in a running condition. They run a youth recovery ranch (charity work) and my work is a freebie. They are paying for parts but that's all.

OK, when I started going over the vehicle it became obvious this has been abused and neglected for some time. I won't go over all the details, but will get to the crux of this post. When I got around to firing up the engine, I noticed it is VERY hard to get started, but even then the firing is VERY erratic. Looking at the magneto I see the wire that would normally go to the points, is instead wired directly to the ignition switch. The only other wire off the magneto goes to the spark plug.

The wiring diagram that came with the vehicle, shows a set of points, the Chilton manual for that series engine shows points, but there are NO points I can find ANYWHERE on this engine. The magneto sits just above the flywheel, and there is a magnet in the flywheel for coil induction, but no points.

I pulled the flywheel expecting them inside, but nothing but the alternator stator is mounted to the engine block. The rotor magnets for the alternator are inside the flywheel drum itself.

According to the Chilton manual they could also be outside, actuated by a cam driven rod. The only opening in the area they show, is the adjustment window for the valves (side valve engine). Talking this over with everyone I know locally, the only possibility, is it might be electronic ignition, and no points, BUT there is no circuit board either.

I have all the numbers from the engine and will post them here. I am wondering if anyone has ANYTHING that might help me get this old beast going?

The engine is a Briggs and Stratton, 11HP, horizontal shaft. It looks like there might be some sort of gear reduction on the output side, before it gets to the torque converter drive.

The numbers are as follows

model
232417

type
0215-01

code
79120411

Thanks

 

[Buckshot 1]

:smile: Check those engine numbers again. As my book does not show those numbers. With the SN: being 79, it is a points engine.

 

[reynoldston]

Looks like you must have module type coil and no ignition points. Sounds like you must have spark seeing it will start. Start with
your other items, compression, timing and fuel. I would go in that order because you might have valve problems???

 

[ILENGINE]

The engine may have been originally a point type engine, but if the ignition module has been changed, it could of been upgraded to a Magnetron type ignition which eliminates the points.

 

[handirifle]

It has not been upgraded, at least as I can tell. According to the chilton manual, nothing looks remotely like the magnatron setup.

It get spark but weak and almost continous. I checked that before tearing into anything. The prev owner never got it running and I suspect they removed the points and wired past them. It firest about 1/5 as often as it should when it did run.

Compression isn't super high, have not used gauge yet but I doubt that's this engines MAIN problem.

Buckshot
which numbers do not show up?

As for timing I was under the impression, you needed point to time the engine, no? It has a small plug where the plunger for the points would normally come out.

Renoldston
what is a module type coil? Thanks for the info so far guys. I will keep diggging.

 

[handirifle]

OK I did re-check the numbers, and it appears the first 2 digits in the M# are 25, not 23. It's hard to tell cause they are rusted over right at that spot. My brother in law just stopped by and he feels it doesn't need points. There is a magnet on the outside of the rotor, and a pick-up point on the magneto coil that sits above it. my concern is there is no adjustment horizontally for timing, only vertical adjustment of the magneto coil.

The coil is wired so that it receives 12v to the primary coil continuously. Is there something inside the magneto coil that the rotor magnet triggers to release power to the secondary side? Otherwise the secondary always has power too. Which this makes sense, cause the spark I get, is not a timed spark like I am used to seeing, but almost continuous. It does appear to get stronger when the magnet comes up, but still sparks.

Like I mentioned, there is no accommodation for external points, as they are cam driven and no openings are there for that. The Magnatron systems have a lot more parts on the crank than this has as well. Sorry for the lame description, but I didn't look for the parts names, since the parts were not there.

 

[ILENGINE]

first thing is if you have 12v to the small wire coming off the to coil (ignition module) is toast. the small wire should be connected to the M terminal on the key switch, which should go to ground when the key is turned off. The Magnetron ignition is a self contained electronic ignition module so there is no other circuit board. I have on more than one occasion when a point engine has a badly corroded ignition module that I know is bad, is unbolt the module and jerk the wire out of the points and replace with the magnetron unit, which if this was a point engine somebody could of removed the points in install a magnetron module in place of the point type module.

Just remember if you are reading 12v at the module at any time, then the module is toast and you also have a key switch problem to go with it.

 

[handirifle]

first thing is if you have 12v to the small wire coming off the to coil (ignition module) is toast. the small wire should be connected to the M terminal on the key switch, which should go to ground when the key is turned off. The Magnetron ignition is a self contained electronic ignition module so there is no other circuit board. I have on more than one occasion when a point engine has a badly corroded ignition module that I know is bad, is unbolt the module and jerk the wire out of the points and replace with the magnetron unit, which if this was a point engine somebody could of removed the points in install a magnetron module in place of the point type module.

Just remember if you are reading 12v at the module at any time, then the module is toast and you also have a key switch problem to go with it.

OK I found this web site The Magnetron Ignition System that helps me understand it a little better. I know the coil has two wires (3 actually if you count the plug wire) that both appear to come off the same spade connector, and both of these were wired to the ign switch. I will check to see if there is 12v to them, I have not done that as I would have expected to find 12v coming from the ign switch, but I see what you are saying about the grounding. I assume THAT is what kills the engine?

If you watch the little tutorial I linked to, it shows only a wire to the top of the plug and a smaller wire, that LOOKS like it is supposed to be a ground. The ign switch is cruded up pretty badly, so I will have to clean it to see if it's labeled "M" at that terminal.

So is there no adjustment for spark timing on this? As mentioned earlier, there doesn't appear to be any lateral adjustment on the slots of the coil, only vertical. While I am on the subject of the coil, should the coil/rotor gap be about .008-.010" on a magnatron unit? Assuming that is what this is.

 

[reynoldston]

A module type coil is a electronic coil that picks up off a magnet instead of ignition points. Ilengine is right about burning the coil if 12 volts positive gos to it. that wire turns off the engine when it is runing from negetive not postive.

 

[handirifle]

A module type coil is a electronic coil that picks up off a magnet instead of ignition points. Ilengine is right about burning the coil if 12 volts positive gos to it. that wire turns off the engine when it is runing from negetive not postive.

That part makes sense now, I need to see if it ever gets 12v, most likely NOT if this IS a magnatron coil. According to the little tutorial it shows a schematic that has the second wire grounded. I assume from what you guys are saying the wire ONLY grounds when you are shutting the engine OFF.

I will check to see if the switch connection goes to ground.

Hopefully that is what this system is, then i can look for other issues. The rotor needed pulling anyway cause there was so much crud in the alternator it might have broken a wire from spinning all the junk around.

The good news is there isn't any backfiring or spitting out the carb, so most likely the valves are not far off, but I can check that. This carb looks like it was made in the 30's. I saw better designs on flat head v8's.