Briggs 8hp crankshaft

[trooper-v-modelB]

Couple of questions - Are the 7hp and 8hp crankshafts interchangeable? (7hp is a plain bearing, while the 8hp is a ball bearing)

Does anyone know of a part listing for 8hp crankshafts for Model Series: 195400? That lists the dimensions and part numbers of the crankshaft.

 

[trooper-v-modelB]

I have answered some of my own questions with some help from a member here. I found these too websites below that list the dimensions and the crankshafts that come with shortblocks respectively.

https://www.smallenginesuppliers.com/html/engine-specs/briggs/Briggs_19A400_19B400_19C400_19E400_19F400_19G400_190400_192400_194400_196400_197400.pdf

https://www.smallenginesuppliers.com/html/engine-specs/briggs/Briggs_Shortblocks.pdf

From what I can tell to be able to use a clutch I need part number(s): 497542, 492473, 493043, 493292, 398537.

Does anyone know which one will work the best?

 

[Neck]

What is it you are trying to do?

 

[The Restore Kid]

I am pretty sure the 7 is a shorter stroke???? :shrug: I know they use a different rod and cap..

 

[trooper-v-modelB]

I found a 8hp IC shortblock, but the output shaft is Tapered Tapped 5/16-24
4-11/32 Measured from Flange mounting face on ball bearing, horizontal crankshaft engine. The block was used on Model Series: 195400.

I was hoping to figure out which crankshaft would work to replace it so I can run a minibike clutch.

 

[Neck]

I believe all 8 horse flathead Briggs with straight output shafts are 1 inch. You can buy a 1 inch clutch, but they cost more than a 3/4 inch clutch.

 

[trooper-v-modelB]

I am replacing a 7hp engine that got blown up last summer in my Tote Gote 780 Nova. The clutch is still good. My plan was to just pull off everything from the 7hp and put on the 8hp short block, but sounds like the 7hp crankshaft won't work. Any suggestions?

 

[Neck]

Your best bet, would be to find another I/C crank or another engine. Turning the tapered crank down to where it was straight would make it too small for your clutch.

 

[trooper-v-modelB]

Does the crank have to come from an engine with dual ball bearings?

 

[Neck]

I'm not sure, I would have to measure my cranks to be positive.

 

[The Restore Kid]

I believe all 8 horse flathead Briggs with straight output shafts are 1 inch. You can buy a 1 inch clutch, but they cost more than a 3/4 inch clutch.

I've seen 3/4 inch dual bearing 8 horse flatheads.. with a HUGE HOLE in the block.. :laugh:

 

[Tim Wilson]

I thought the ball bearing engines had a longer 1" output shaft, and could be straight or tapered. My plan was to swap a non bearing short shaft crank into a bearing case or have the crank machined to work with my clutch. Tapered shaft won't work.

 

[The Restore Kid]

You can turn them down.. Thats about the easiest thing to do.. The cost of having it cut down and a keyway cut, won't be much any more expensive than buying a different crank, WHEN ya manage to find a 3/4 bore for sale, some day.. :laugh:

 

[Tim Wilson]

What do you mean by 3/4 bore?

 

[Tim Wilson]

Briggs crank

I have a Salisbury 500 clutch on my twister for use with a 1" output shaft, but the bearing crank doesn't neck down close enough to the block to allow the belt to align with the driven clutch. The overall length can just be cut off, but i will have to have the collar turned down i think about 3/4" farther back. Also if anyone is looking for a tapered shaft to turn down to 3/4", I have one for sale.

 

[The Restore Kid]

What do you mean by 3/4 bore?

3/4 inch O.D.

3/4 inch bore slides onto it..

 

[Tim Wilson]

Thanks for the reply (i realize it sounded like a dumb question)
I would have thought a clutch with a 3/4" bore would be more common than a 1"

 

[The Restore Kid]

Thanks for the reply (i realize it sounded like a dumb question)
I would have thought a clutch with a 3/4" bore would be more common than a 1"

by far.. :laugh: 3/4 inch is pretty un common size in 8 horse though..

 

[Oldsalt]

I can turn a tapered crank down to 3/4" OD [and cut the keyway] IF there is enough length before the taper gets smaller than 3/4". Done it before. As I recall about 2-5/16" is the length of a "standard" 3/4" OD factory Briggs and Tec output shaft and is right for a OldMiniBikes centrifugal clutch. But the owner should specify what they want and provide a sketch showing all dimensions. The gear does not have to be removed and the length dimensions can be from the outside of the gear.

Turning a 1 inch OD shaft to 3/4 inch is also a piece of cake and I'm able to do that quickly. Some of them have 3/8 NF tapped hole in the end rather than 5/16 NF but that doesn't hurt anything.

I will do them for free but I would like to be reimbursed for the return shipping [seems to run about 17-20 bucks if Priority Mail is used with insurance]. In any case please make certain that what you want done has enough metal there to be accomplished. These cranks are [I have every reason to believe] made from semi-steel. Not straight cast iron because some steel is in the mix...but in any case we cannot expect to add metal and then machine.

PM me.