Electric Start on Vintage B&S Engine

[Skywatcher]

Greetings All and Happy New Year

Working on a 1973 B&S engine on a Cub Cadet snow blower. The engine is equipped with the B&S 120 volt electric starter and the plastic pinion disintegrated and fell off long ago. The IPL for this engine says to use the 280104 pinion, but that pinion doesn't work on this engine. The pinion fits the starter motor just fine, but the gear teeth are the wrong pitch for the ring gear on the flywheel. I haven't actually measured the tooth to tooth distance on the flywheel as it was getting late and I was getting cold, dropped down to -29ºC (-20ºF or 244ºK) last night. The ring gear on the engine has a smaller pitch than the plastic pinion, so the two don't mesh. The metal pinion gears are a larger pitch than the plastic ones, so they definitely won't work. Any suggestions? All the best,

Sky

Engine Details:
Make: B&S
Model: 190412
Type: 0821-01
Code: 73083010

[hanz63]

Brrrr! There are quite a few notes regarding the 0821-99 engines with the IPL. Are these possibly of help? Best of a New Year to you and all on the board.

[SUKI]

Sounds like someone mismatch parts years ago.

[38racing]

I had a 74 B&S IIRC on a toro blower. The 120 starter didn't work . I put a 12v mower engine starter on it using the standard plastic gear which comes up as 280104. It worked fine.

[Skywatcher]

Hi Again

Interestingly enough, when I looked up this engine on Partstree this morning and looked at the breakdown of the starter motors, there is no part number given for the pinion (key # 783) in the parts listings. This would indicate to me that the original pitch pinion has long been NLA. Looking at the ring gear, it would appear that there was a specification change for the ring gear made on February 27th 1975. I suppose one option would be to find a good used flywheel with ring gear from and engine with date code 750228 or later so the standard plastic pinion would have a better chance of meshing properly. Any further thoughts?

Sky

[KE4AVB]

Curious do you have a steel or is it aluminum ring gear?

[38racing]

Hi Again

Interestingly enough, when I looked up this engine on Partstree this morning and looked at the breakdown of the starter motors, there is no part number given for the pinion (key # 783) in the parts listings. This would indicate to me that the original pitch pinion has long been NLA. Looking at the ring gear, it would appear that there was a specification change for the ring gear made on February 27th 1975. I suppose one option would be to find a good used flywheel with ring gear from and engine with date code 750228 or later so the standard plastic pinion would have a better chance of meshing properly. Any further thoughts?

Sky

I had downloaded an IPL for a 1904... Section under where 783 was shown it wasn't listed but down in a ** for what the starter kit included it showed 783 as 280104
My ipl shows only one flywheel 298260. Has different part number flywheel plus ring gear depending on with an alternator or not. 298260 seems to supercede to 690615 which is number on a much later 1924.... series.

[Skywatcher]

Hi 38

Thanks for being an extra set of eyes on this one. I does appear then that the flywheel part # subs up to a newer spec flywheel and ring gear assembly. KE4, I'll check to make sure when I get back into the shop on Tuesday, but I'm thinking it's a steel ring gear as it looks very similar to the fine toothed steel ring gears on Tecumseh Snow-King engines. A magnet will be the simplest test.

I'll probably finish repairing the furl system, get the unit back together without the electric starter and see how the machine works before contacting the customer and finding out what he wants to do about the electric start. I have a snow blower with a Tecumseh Snow-King engine (HMSK100-159212T-5010D) which I believe is a 1995, bought it in 2008 and have never used the electric start. The engine will start on the first or second pull every time. Not sure how easily a 47 year old B&S snow engine will start, guess I'll have to do a cold soak and try it. All the best,

Sky

[KE4AVB]

Here is a copy of the IPL from the Briggs Power Portal. It should explain why I ask about the ring gear. I had the past with other Briggs engines where a tech installed the wrong starter. The plastic gear is only meant to be used with the plastic and aluminum ring gears and not the steel one.

https://1drv.ms/b/s!AhP6VW6j_ZC5mABV5Cm1lxGd3yT2