Coil testing and ID on B&S engine

[GBertolet]

I was given a roto tiller with a B&S engine. I have no spark. I replaced the points & condenser, still no spark. It's an old model engine, a 81702 9446-13, SN 5902180. I have the coil out, and want to test it. There are two coils listed for this engine. I believe I have the 291617 coil. Discontinued, NLA, of course. Anyhow, how do I test this thing? What am I to see? I have continuity between the two small wires, and that's it. No continuity, between any other wires, including the high voltage and ground.

The last time this engine has ran, was 15 years ago. I worked fine then. I have located a NOS coil, which is a bit pricey, so I want to be sure, mine's actually bad, before I buy it. If the methodolgy of dating is the same between codes and serial numbers, this would make this a 1959 engine.

 

[bigbadbob]

https://www.google.com/search?q=bri...me&ie=UTF-8#kpvalbx=_HKDnX5vgHszh-gSr1Z7wAg13

I have had one test good,,, was bad.
Maybe moisture from being outside all the time,,,
Lotsa used coils around

 

[GBertolet]

Is it possible to convert this to a breakerless ignition, using a different coil? I saw, on one of Taryl's videos, he did this to an old B&S engine, but I wouldn't know what coil he used, or if this would be applicable to my engine.

 

[Lcfd1124]

Is it possible to convert this to a breakerless ignition, using a different coil? I saw, on one of Taryl's videos, he did this to an old B&S engine, but I wouldn't know what coil he used, or if this would be applicable to my engine.

You can try baking the coil, I've had it work on some old coils

 

[GBertolet]

This coil has a big chunk of the bakelite missing. Looks like the mice have been chewing. The high tension lead to ground shows open, so I guess it's junk. I found a complete N.O.S. one, for $40 on the internet. That's the best priced one I could find, so I ordered it. It was the last one they had.

 

[GBertolet]

New coil came, tested good, engine starts now. The insulation on the secondary was so brittle, it cracked, where I bent it down to attach to the sparkplug. I put some tape around it there. I don't know if there is a better fix for this or not. This 3 leg coil must have sat for many years for this to happen. It came in an ancient B&S box.

I need some carb parts to complete the job, as the engine doesn't stay running long. I found the float has a pin hole in it, flooding out the engine, and the breather hose is torn. Probably should get a new bowl gasket also.

 

[ucm931]

New coil came, tested good, engine starts now. The insulation on the secondary was so brittle, it cracked, where I bent it down to attach to the sparkplug. I put some tape around it there. I don't know if there is a better fix for this or not. This 3 leg coil must have sat for many years for this to happen. It came in an ancient B&S box.

I need some carb parts to complete the job, as the engine doesn't stay running long. I found the float has a pin hole in it, flooding out the engine, and the breather hose is torn. Probably should get a new bowl gasket also.

I'd normally recommend removing the spark plug connector and boot then use adhesive lined heat shrink to repair it, but it sounds like like it would be too brittle to dork round with it that much. If the secondary can't be removed to replace it, paint a couple layers of liquid electrical tape on it.

 

[Mike C.]

This coil has a big chunk of the bakelite missing. Looks like the mice have been chewing. The high tension lead to ground shows open, so I guess it's junk. I found a complete N.O.S. one, for $40 on the internet. That's the best priced one I could find, so I ordered it. It was the last one they had.

Sorry if someone has already stated this,but be careful when testing ignition coil secondaries with a continuity tester in a digital multi-meter.Usually at anything greater than 50 or so ohms of resistance,the continuity tester will not beep and show a complete circuit.This does not necessarily mean their is no continuity.The secondary of a good ignition coil usually has several thousand ohms of resistance,therefore the continuity meter won't sound off.This is why one uses an ohm meter,not a continuity tester.

Once again,if you are already well aware of this ,I apologize,but someone may find this useful.

Also,on ignition coils that have spark plug wires attached to a tab on the coil-DO NOT solder the wire to the tab-you will ruin the coil.One merely sticks the wire through the hole in the tab and wraps it around.

 

[GBertolet]

My original coil did have the secondary wrapped around a tab. I sort of wondered on why it was not soldered. That explains it. The new coil secondary is permanently attached.

 

[Stump Shot]

The new replacement coils I purchased for my old 1970's era 3hp and 8hp were electronic and replaced the points and condenser.
Been a while, but a brass float can be solder repaired fairly easily. Might be handy if a replacement is hard to find.

 

[GBertolet]

My coil is a 3 leg coil. I was told I could not convert it to breakerless. Was I told wrong? My float was crinkled a bit, where the pin hole was, so I found a NOS one. I had to pay $17 for it though. I don't know if that was a fair price or not. It was the cheapest one I could find online.

 

[Mike C.]

The new replacement coils I purchased for my old 1970's era 3hp and 8hp were electronic and replaced the points and condenser.
.

You can also just replace the points with a Nova II ignition module and use the original coil on most old points engines (if your coil is good).But,on engines that have extra magnets on the flywheel for charging and lighting circuits,the Nova module won't work

I never found a suitable solution for dealing with a bad coil of the type in the OPs engine other than replacing with the same coil.By now,someone may have come up with a solution-I haven't had to deal with one for a fair number of years.I hope so,because one can find these engines very cheap,but almost always have a bad coil.

 

[Stump Shot]

My coil is a 3 leg coil. I was told I could not convert it to breakerless. Was I told wrong? My float was crinkled a bit, where the pin hole was, so I found a NOS one. I had to pay $17 for it though. I don't know if that was a fair price or not. It was the cheapest one I could find online.

You can tell if in the IPL from Briggs the coil has a superseded part number. You can find at their website.
Good find on the float.

 

[Mike C.]

Well,these folks have found a solution that appears to work:https://www.smokstak.com/forum/threads/briggs-three-legged-armature-coils.89608/

 

[Mike C.]

It seems we now also have this option:https://bolenspartsandsupplies.com/small-engine-parts/291617-briggs-and-stratton-ignition-coil/

I can buy most engines that use this coil for $20 or less,that's a lot of money for the winding only.

 

[GBertolet]

I am trying to find an owners manual for this rototiller. It is a David Bradley (Sears) 785.53001. So far, I cannot find one to download. Can anyone point me to a link to download this?

 

[ray benson]

I am trying to find an owners manual for this rototiller. It is a David Bradley (Sears) 785.53001. So far, I cannot find one to download. Can anyone point me to a link to download this?

Model numbers beginning with 785 (Magna American Corporation, General Power Division)
201 E Brink St, Harvard, IL 60033
old phone numbers - don't know if they are still active.
815/943-7411
815/943-7421
From what I read it is hard to get manuals for the old tillers.

 

[GBertolet]

Thank you Mr. Benson.