How To Remove Briggs Flathead Flywheels

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JTSpeedDemon

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Ok, the general gist on the internet is that these Briggs flywheels are a pain in the butt to remove.
WRONG!!!
Unless your flywheel is like, rusted onto the crankshaft, they are actually pretty easy.

BTW - This is a beat up old tiller engine, NOT a low hour primo workbench queen. So the accuracy of this thread is not compromised by starting with a nice engine. This is also hands-on, real world experience all by me.

Pics are in correlating order with the steps, left to right, going down.

Stock flywheels are cast iron and brittle. Do NOT chip, crack, or break in any way these flywheels! Use common sense and be gentle with it.

EDIT - See post 4 by Hellion. He refers to the proper OEM methods to remove these parts. Please read what he has to say and decide which method you want to use.

Step 1: Remove the blower housing. There is one bolt on top, one on the carb/exhaust side, and one on the other side.

Step 2: Remove the flywheel screen(2 visible hex bolts also with flathead screwdriver slots).

Step 3: Remove the starter clutch. Hold the flywheel with a long screwdriver, using the coil as a stop. Wedge the screwdriver between the gray aluminum fins and not the cast iron ones(See pics).
Hammer on the little tabs on the clutch counterclockwise, minding the flywheel fins. Once it is loose you should be able to spin it off with your fingers.

There is one washer behind the starter clutch, remove it and you should see the timing key.
At this point there is nothing holding the flywheel on except the shaft taper. Take a light hammer and lightly tap on the gray aluminum magnet part of the flywheel, NOT THE CAST IRON PART!
Another very good option that's a little more foolproof is to take a hammer and lightly tap the end of the crankshaft.
The flywheel now should've popped off the taper, and you can simply pull it off and proceed with whatever you were in there to do in the first place.

Installation is obviously the reverse of removal.
When reinstalling the flywheel, make sure the timing key and washer are in.
The manual says to torque down the flywheel nut(in this case the starter clutch) to specs noted below. I tried doing it with a torque wrench on the starter drive, but that just popped the clutch apart.

Flywheel nut torque specs:

Aluminum engines
Series 100200, 100900, 130000........65 ft/lbs
All others.......55 ft/lbs

Cast iron engines
Series 900000.... 60 ft/lbs
All others.......55 ft/lbs


You'll have to use the tab-hammering method and common sense for this part.
WARNING - If you under-torque the starter clutch, you run the risk of your flywheel coming loose at high RPM and shearing the timing key, or worse.
Just put it about where it was before.

I hope this helps someone, but this procedure really shouldn't be feared. Any true small engine tinkerer should be able to do this.
Entirely written by me. :cool:
 

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JTSpeedDemon

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Yup, a casual tinker session in the garage turned into a full ignition points servicing, resulting in a fully running engine!
To be honest I was kinda intimidated by this job, with having to remove the flywheel and all, but I'd do it again in a heartbeat if needed!
 

Hellion

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I cannot fully endorse your methods. :eek: It worked for you and that's fine but I would never pry on or use the aluminum flywheel fins for leverage at any time. Those are the most fragile things on the flywheel. I also would not pry on the starter clutch for any reason. Again, a somewhat fragile piece and not something you want to mess up.


I don't recommend hammering on the 'ears' of the starter clutch as a preferred removal and assembly method. Nuh uh, it's just too problematic and you risk breaking them off; I've seen it happen. There's a special starter clutch tool for it (see below). Furthermore, the preferred "shade tree mechanic" method for removing the flywheel is to pry between the flywheel and the crankcase with a large screwdriver or pry-bar and tap on the crankshaft extension with a plastic tip/brass hammer. There's also a special tool for this that protects the crankshaft--see below.


I think you're taking the fear factor to an extreme. Cast iron is not as brittle as you suggest and it's quite alright to use the cast iron fins to help immobilize the flywheel. In fact there's a B&S factory tool that does just that. Applying light pressure [not hammer blows] to the cast iron fins is not going to hurt it or induce damage to the flywheel as a whole. It very well could... but I place more faith in the B&S engineers and their special tool.

Your How-To is adequate and helpful for someone with limited tools or for a one-time, all or nothing procedure but using a screwdriver and hammer on the soft aluminum fins and starter clutch assembly is a gamble.

List of official tools:

Starter clutch removal tool [Briggs #19244] ($7.62 on Amazon!):


Briggs flywheel holder [Stens #750-083]:


Briggs flywheel puller/knocker [Stens #750-091] --(Place over crankshaft and tap lightly to free flywheel)


And lastly, a Briggs flywheel puller [Briggs #19203] (only works on flywheels that have 2 threaded holes)
 

JTSpeedDemon

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Yes I understand my methods were certainly not perfect. My reasoning behind the aluminum is that aluminum(soft metal) would deform under heavy impact(I was actually only lightly tapping it with a light hammer), but cast iron could chip.
If I had the OEM tools I certainly would've used them, but this is the budget git-r-done method.
And my flywheel didn't have any flywheel puller holes.
I'm actually grateful you pointed this out, since this is the FAQ, where lots of newbies will be seeing this.
 
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