K91 Convert Starter-Generator?

[71_Bronco 1,072]

Was working out in the garage today, and had an idea.

 

I know a Starter-Generator K91 is not very common. However, it seems like the bigger motors with Starter-Generators were a little more plentiful (like the K181 on the Commando 8 with a Starter-Generator).

 

Would it be possible to use a starter generator off a K181 or something of that size, and fit it to the K91?

 

Obviously some mounts would have to be fabricated, and a pulley fixed to the flywheel, but in theory, it seems like a pretty sound concept, at least from my limited experience.

 

Is this doable? Or is there something else I'm not taking into account?

[953 nut 57,899]

The factory made some K-91 S/G models, I think @Aldon had one a few years back at the big show

[AMC RULES 37,146]

@formariz

[Achto 28,777]

3 hours ago, 71_Bronco said:

Is this doable? Or is there something else I'm not taking into account?

 

Very doable indeed. The engine does not care how it is turned over and the S/G does not care what engine it is connected to. The AC Delco S/G is the same size on all of the Kohler engines, Briggs used one with a shorter body on their vertical shaft engines. Clockwise rotation if you are going to drive it on the fly wheel side, counter clockwise if you are going to drive it on the PTO side.

 

I've seen a few K91's with a S/G one of which was an LP model on a floor sweeper.

[ACman 7,630]

Ok fellas I’ve been stumped  looking at my S/G pulley on my RJ engine and it has a bolt . The blue one  is one I gave to @pullstart and it had a nut which seems to be the norm . I have a Schnake recoil I bought from @Jake Kuhn I want to install on the red engine but that bolt has me confused . I do know this engine had a full rebuild with paperwork from machine shop if I could find it . Possible threads machined off and taped because of messed up threads ? @AMC RULES @Shynon @Lane Ranger @wallfish @squonk Thoughts or answers  . I haven’t had the pulley remote yet. You guys know my situation. Heck I couldn’t even get to the tractor show 2 miles away from me this last weekend .  

 

 

Edited September 27, 2021 by ACman

[wallfish 17,492]

7 hours ago, ACman said:

Possible threads machined off and taped because of messed up threads ?

Think you're right. That should be the threaded end of the crankshaft for a nut

[Lane Ranger 11,125]

8 hours ago, ACman said:

Ok fellas I’ve been stumped  looking at my S/G pulley on my RJ engine and it has a bolt . The blue one  is one I gave to @pullstart and it had a nut which seems to be the norm . I have a Schnake recoil I bought from @Jake Kuhn I want to install on the red engine but that bolt has me confused . I do know this engine had a full rebuild with paperwork from machine shop if I could find it . Possible threads machined off and taped because of messed up threads ? @AMC RULES @Shynon @Lane Ranger @wallfish @squonk Thoughts or answers  . I haven’t had the pulley remote yet. You guys know my situation. Heck I couldn’t even get to the tractor show 2 miles away from me this last weekend .  

 

 

All you can say is the crankshaft is shorter than you need !  Maybe a hex threaded bolt with no head and two flat sides on your red 4 hp Kohler could accommodate the Schnacke hex head nut?   The hex head nut will hold.   Something was changed for sure from normal.  

 

Edited September 27, 2021 by Lane Ranger

[ACman 7,630]

@Lane Ranger thanks . Jake does provide a machine washer for proper spacing. I’ll get the pulley off and see what’s up and start a new thread . 

[71_Bronco 1,072]

Thanks all for the replies thus far.

 

I am aware of the S/G K91's, but finding an original seems to be pretty dang hard (and costly).

 

Was just trying to figure out if a "poor-mans conversion" was doable by taking a S/G off another engine and fabbing brackets to make it work on a regular K91.

[ACman 7,630]

2 hours ago, 71_Bronco said:

Thanks all for the replies thus far.

 

I am aware of the S/G K91's, but finding an original seems to be pretty dang hard (and costly).

 

Was just trying to figure out if a "poor-mans conversion" was doable by taking a S/G off another engine and fabbing brackets to make it work on a regular K91.

‘there’s usually a pulley or two on fleabay and finding a generator shouldn’t be to hard . Brackets are the issue . Jim @WHX?? was trying to find or make some too . @formariz you still have any s/g engines around. Also @fireman .

 

 

[Shynon 7,475]

21 hours ago, ACman said:

Possible threads machined off and taped because of messed up threads

 someone used impact to put the nut on and broke off the nose. I would pull the bolt and if the crank is threaded install a threaded stud and then install the schnacke nut.

 

[adsm08 2,643]

On 9/26/2021 at 8:36 PM, Achto said:

 

Very doable indeed. The engine does not care how it is turned over and the S/G does not care what engine it is connected to. The AC Delco S/G is the same size on all of the Kohler engines, Briggs used one with a shorter body on their vertical shaft engines. Clockwise rotation if you are going to drive it on the fly wheel side, counter clockwise if you are going to drive it on the PTO side.

 

I've seen a few K91's with a S/G one of which was an LP model on a floor sweeper.

 

I think all the Briggs units were shorter. I have a horizontal shaft Briggs that has an S/G body that is much shorter than the ones on my Kohlers.

[Achto 28,777]

17 minutes ago, adsm08 said:

I think all the Briggs units were shorter. I have a horizontal shaft Briggs that has an S/G body that is much shorter than the ones on my Kohlers.

 

Interesting.  My friend is into Simple City tractors. His cast iron horizontal shaft Briggs engines all use the same S/G as my Kohler's. His vertical shaft engines use a shorter body AC Delco S/G. Must come down to what the manufacturer had room for on their product. 

Edited September 28, 2021 by Achto

[squonk 42,525]

On 9/26/2021 at 8:36 PM, Achto said:

 

The AC Delco S/G is the same size on all of the Kohler engines, 

Not entirely Dan. I have an original 702 engine here that I pulled off a old barn find that has a shorter body. so it uses a shorter bracket.

 

[Lane Ranger 11,125]

Yes there were two or three different starter/generator brackets used on Wheel Horses.  I use to buy the brackets at swap meets to resell due to the differences. 

[Achto 28,777]

11 minutes ago, squonk said:

I have an original 702 engine here that I pulled off a old barn find that has a shorter body.

 

Guess that I need to buy more tractors so that I have enough to make comparisons. 

[squonk 42,525]

12 minutes ago, Achto said:

 

Guess that I need to buy more tractors so that I have enough to make comparisons. 

I hear someone is "having a sale" at a plowing event! 

[adsm08 2,643]

14 hours ago, Achto said:

 

Interesting.  My friend is into Simple City tractors. His cast iron horizontal shaft Briggs engines all use the same S/G as my Kohler's. His vertical shaft engines use a shorter body AC Delco S/G. Must come down to what the manufacturer had room for on their product. 

 

Maybe.

 

I tried to swap them between my two horses last year when I had an S/G failure on the main tractor, and the one on the Briggs engine is almost two inches shorter than the one on the K181, but the S/G unit from my JD K181 is the same.

[formariz 11,994]

On 9/26/2021 at 5:02 PM, 71_Bronco said:

Was working out in the garage today, and had an idea.

 

I know a Starter-Generator K91 is not very common. However, it seems like the bigger motors with Starter-Generators were a little more plentiful (like the K181 on the Commando 8 with a Starter-Generator).

 

Would it be possible to use a starter generator off a K181 or something of that size, and fit it to the K91?

 

Obviously some mounts would have to be fabricated, and a pulley fixed to the flywheel, but in theory, it seems like a pretty sound concept, at least from my limited experience.

 

Is this doable? Or is there something else I'm not taking into account?

It’s actually relatively easy to do. Components are easy to get . The only tricky part is fabricating the bracket. If you need photos and details of one I can provide that. I am lucky enough to own a few of them NOS never started. I have also seen a set up with the genny in front of engine rather than behind. That way one can use the more common granny turning in the opposite direction.