Briggs 3.5hp Question

[csampson311]

I picked up a very old lawn mower today with a Briggs 3.5hp verticle engine for free. I want to flip it so that it has a horizontal shaft that I can mount on my bike. It says it is the 148cc model but its so old I cant find much information on it. Im trying to find out what clutch I can buy that will fit on the crank shaft. What trips me out it the shaft design. It goes from narrow to fat. Then there's a threaded hole at the end where the lawn mower blade mounted with a screw. Not sure if this is normal or what because every other shaft I have seen is way different.

 

[the-cyborg]

Don't waste your time trying to convert something that is not, to something it will never be.
Save yourself allot of headaches, wasted time and effort, and get your hands on a horizontal shaft engine.

 

[DudeRadster]

Don't waste your time trying to convert something that is not, to something it will never be.
Save yourself allot of headaches, wasted time and effort, and get your hands on a horizontal shaft engine.

I agree. Make yourself a really big remote control helicopter. That's the only use I can think of for this thing.

 

[the-cyborg]

I agree. Make yourself a really big remote control helicopter. That's the only use I can think of for this thing.

Or a lawn mower

 

[sexyvicta]

you forgot to pull off the blade driver man. Put the blade retaining bolt back in and then use a puller to get off the driver.

it dosn't look that old. If it was older it would be 3hp. But anyway the 3hp, 3.5, 375 etc are all much the same.

Shaft size should be 5/8 with a couple keyways and the threaded hole so fiting a clutch will be easy/ the least of your problems

 

[csampson311]

you forgot to pull off the blade driver man. Put the blade retaining bolt back in and then use a puller to get off the driver.

it dosn't look that old. If it was older it would be 3hp. But anyway the 3hp, 3.5, 375 etc are all much the same.

Shaft size should be 5/8 with a couple keyways and the threaded hole so fiting a clutch will be easy/ the least of your problems

Oh I see! haha That makes sense now. Thank you. Does the puller have to be specific for this shaft or just a pry bar?

 

[sexyvicta]

something like that.

 

[csampson311]

And another thing...

Hey guys, just another quick question. Does any one know where I can get a manual so I can properly torque the bolts when Im done? Preferably an online source or any other place that can give me this info.

 

[robbie]

Shaft size should be 5/8 with a couple keyways and the threaded hole so fiting a clutch will be easy/ the least of your problems

Standard size for a lawnmower is 7/8". If you want to use this on a kart or bike you'll want to get the crank shaft resized at a machine shop.

 

[sexyvicta]

ah yes you are correct. Typo i ment to say 7/8. But you should be able to suss a 7/8 clutch

 

[csampson311]

Aw man that sucks! Where can I find a 7/8 chain driven clutch. Ive seen a couple but they are all belts. Could i use a file with the engine running to make it 5/8?

 

[sexyvicta]

wait. did you measure it? could be 3/4. I get confused with these old world units of measurement. I'm sure the small block briggs vertical shaft are a smaller shaft than the quantums tho and i think quantums are 7/8.

 

[robbie]

Small to mid size lawnmowers are standardized at 7/8", but measure it to make sure.

 

[sexyvicta]

yeh i've had about 8, 3hp, 35 and 375 148cc engines on mowers i've fixed up and they were all smaller size shaft than the 190cc engines which im pretty sure are usualy 7/8 altho they also can come with the smaller shaft

edit: unless im getting confused and the bigger ones are inch shaft. Dunno i just sold my last 35 classic so have nothing to measure

 

[csampson311]

I'll measure it to make sure but I can't right now. I still can't get that driver off I tried the puller and a pry bar but it's still not budging.

 

[sexyvicta]

Soak it in crc/wd40. They can be realy hard to get off. Maybe take it to a mechanic or engineer who has a realy big puller. Thats what i do when my little puller wont do it

 

[jrmints1415]

not wd40 try PB blaster wd40 wont help much but penetrating oil will!

 

[csampson311]

Sorry guys... I finally got the driver off and found out the motor is no good. I opened up the crank case and from sitting for many years in sludgy oil the gears and rod were rotted. I gave up so now I'm just gna save for a 6.5hp horizontal

 

[DustinWolfe]

not wd40 try PB blaster wd40 wont help much but penetrating oil will!

wd 40 is penetrating oil