Briggs and Stratton flywheel nut removal

[benson1980]

Hi all,

I am attempting a repair on my Makita lawnmower which has a B+S 675Exi engine. I believe that the flywheel key is the culprit for difficult starting/rough running and therefore have taken it apart to access it.

I have bought the special (and very expensive) tool that supposedly both acts as the flywheel puller, and holds it in place to remove the bolt. I have tried the strap wrench method and as you can see this has just caused the fins to shear off as I tightened around them. I have therefore bought a replacement secondhand flywheel off Ebay. This repair is not going well...

Now that I thought I had the right tools, I cannot for the life of me work out how the tool works to hold the flywheel securely in place whilst I remove the nut. The bolts just drop down loosely into the two holes. They don't actually secure into anything underneath. The instructions say hold the bolt in place with a wrench, but I'm just holding onto a loose bolt!

Is anyone able to tell me what I'm missing, or best way of holding the flywheel in place? My other issue appears to be that my blade rotates around the spindle freely so I can't jam it from underneath. Was going to try and fix that after I've sorted this problem.

Thanks

 

[StarTech]

I see you already been donating blood. <LOL>

You use a pull bar in the square hole to hold the tool while you remove and when you retorque the nut back to 60 lb/ft (81.3 Nm). Can't tell if you need 3/8 of 1/2 square drive end but will be obivious when you try the pull bar. And you definite need some penetrating oil on the nut due to the amount of rust I see.

 

[benson1980]

I see you already been donating blood. <LOL>

You use a pull bar in the square hole to hold the tool while you remove and when you retorque the nut back to 60 lb/ft (81.3 Nm). Can't tell if you need 3/8 of 1/2 square drive end but will be obivious when you try the pull bar. And you definite need some penetrating oil on the nut due to the amount of rust I see.
View attachment 63891

Yes good spot- I might have sliced my finger a bit trying to undo it! Nothing too serious...

Thanks for the pointer- really appreciate it. Will give it a go tomorrow. And yes I've given it a good soak with plus gas and just added some more for good measure to leave overnight.

 

[Bertrrr]

The only way I ever pulled a flywheel is to pry up from 2 sides 180 degree apart and Hit the top of the shaft with a good hammer, you need to back the nut off so it's flush with the shaft so it doesn't mushroom.
Have a friend pry up on the fly wheel and give it a good Pop with a ball peen hammer and it will pop loose , it's a tapered shaft so doesn't need to move much to free up.
Use an Impact to break the nut loose , no need to hold the flywheel it will break the nut loose

 

[benson1980]

Hi both- thanks again for your help with this problem. Managed to remove the flywheel nut using the above method, with that metal plate tool and putting a breaker bar through the square hole. Needed another pair of hands. Completely useless instructions from Briggs and Stratton and their tech support don’t reply either….

also used the pry method as advised, as again there’s no way the tool and following the instructions were going to get it off.

Bad news is flywheel key was actually fine. I’ve already serviced it, put fresh oil and petrol in, and cleaned the carburettor so at a bit of a dead end trying to fix it. I can just about get it started when cold but trying to start it again when warm is really difficult, and the starter rope will jerk back. Ended up buying a new Honda mower so will hopefully have some more success with that.

 

[slomo]

I pull flywheels with an air hammer and a prybar. And an impact gun on the nut, to LOOSEN only. Torque the nut back to factory specs when done.

 

[benson1980]

This is the outrageously expensive tool from Briggs and Stratton for this engine series. I have no idea how a metal plate and a few bolts can be just under £100:

https://www.briggsbits.co.uk/acatalog/19619-Puller-450E-500E-550E-600E-850-950-4209.html

Won't be buying another mower with a briggs engine.

 

[unkwnmike]

Hi all,

I am attempting a repair on my Makita lawnmower which has a B+S 675Exi engine. I believe that the flywheel key is the culprit for difficult starting/rough running and therefore have taken it apart to access it.

I have bought the special (and very expensive) tool that supposedly both acts as the flywheel puller, and holds it in place to remove the bolt. I have tried the strap wrench method and as you can see this has just caused the fins to shear off as I tightened around them. I have therefore bought a replacement secondhand flywheel off Ebay. This repair is not going well...

Now that I thought I had the right tools, I cannot for the life of me work out how the tool works to hold the flywheel securely in place whilst I remove the nut. The bolts just drop down loosely into the two holes. They don't actually secure into anything underneath. The instructions say hold the bolt in place with a wrench, but I'm just holding onto a loose bolt!

Is anyone able to tell me what I'm missing, or best way of holding the flywheel in place? My other issue appears to be that my blade rotates around the spindle freely so I can't jam it from underneath. Was going to try and fix that after I've sorted this problem.

Thanks

I had same problem. You have to take off the center nut to get to fly wheel. Must you their puller. $20.00 on amazon. Comes off 123.

 

[benson1980]

I had same problem. You have to take off the center nut to get to fly wheel. Must you their puller. $20.00 on amazon. Comes off 123.

I used a £5 pry tool in the end. But, you try and prep for the job and it leads you to presume you need their special tool. To be honest it was mainly holding the flywheel in place whilst loosening the nut that seemed to be the main issue and reason I bought it; I don't have an impact driver/wrench and the strap wrench method wasn't working against the plastic fins.

 

[bertsmobile1]

I used a £5 pry tool in the end. But, you try and prep for the job and it leads you to presume you need their special tool. To be honest it was mainly holding the flywheel in place whilst loosening the nut that seemed to be the main issue and reason I bought it; I don't have an impact driver/wrench and the strap wrench method wasn't working against the plastic fins.

Which is why the make the idiot proof tool in the first place.
Professionals use air guns or high speed battery impacts which only need hand pressure to hold the flywheel
After that it is a prybar or two and a hammer
I use a 3 leg puller with an air gun that will pop nearly every flywheel and you can hold the flywheel still enough with your fingers
Special tool that are made in very low volume and sold in even lower numbers will be very expensive because of the logistical / storeage costs if nothing else.
A pallet sitting on a shelf in a warehouse costs money, a lot more money than most would believe , the pallet space itself costs money every day of the week , regardless of how many times it is accessed then there is a picking cost a despatch cost and a retail profit .
Before it is made there is a design cost, a testing cost , and an inventory listing cost .
Then there is the profits in using it.
If it saves me 5 minutes 12 times a day it has made me a $ 76 profit.
If it does the same for the shops in town that blows out to a $ 150 profit
If it saves Joe Stupid the cost of a new fan that they broke getting the flywheel off then again it pays for itself very quickly .

IF no one was allowed to make profits then we would still be cutting grass with sythes & sickles .