Push mower oil leak Briggs

Scrubcadet10

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I use a multi purpose puller tool, to take off flywheels.

Sunex Tools Automotive 8-Way Reversible 2 or 3-Jaw Puller

Just don't hit the flywheel with a hammer, this can weaken it and cause it to possibly shatter while running. Or at least that's what I've heard.
 

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Those couple of missing fin's won't hurt anything.

Unless your replacing the seal under the flywheel, there's no reason to remove it..

The insides look as I'd expect from an older used engine.

A wire brush (on a drill motor) works great for removing carbon. I would gently scrape the heavy carbon off first..

You can re-ring once the piston is pulled and lightly honed

As for the valves, I'd spin the engine over slowly and look at the valve seats (open). Un-less damaged, I put some fine sand paper in-between the valve and head and ALMOST close the valve fully. Now you can spin the valve, remove excess carbon, etc from both surfaces.

It's very rare I remove a valve.
 

rwomack

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Those couple of missing fin's won't hurt anything.

Unless your replacing the seal under the flywheel, there's no reason to remove it..

The insides look as I'd expect from an older used engine.

A wire brush (on a drill motor) works great for removing carbon. I would gently scrape the heavy carbon off first..

You can re-ring once the piston is pulled and lightly honed

As for the valves, I'd spin the engine over slowly and look at the valve seats (open). Un-less damaged, I put some fine sand paper in-between the valve and head and ALMOST close the valve fully. Now you can spin the valve, remove excess carbon, etc from both surfaces.

It's very rare I remove a valve.


Ok so I assume you can remove rod and piston and hone w/o removing crank? Flywheel must come off if crank is pulled. Also, once I do have piston and rod out, that’s when I would need to check the bore to determine ring size?
 

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If you pay close attention, yes you can hone with the crank still installed. Your just doing a light hone for the new rings.

If you want to pull the flywheel and crank, as posted above, a puller is best.

In a pinch, you can put pressure between the block and flywheel (lifting the block slightly) and smack the "flywheel end" of the crank (use a piece of aluminum in-between so you don't damage the crank end). It should pop off fairly easily..

Once the pistons out, carefully remove the old rings and measure "ring end gap" for the compression rings. It'll give you a good idea how worn they are.

As for replacements, I don't know what / if Briggs offers oversized rings.

Worst case scenario, STANDARD new rings will be considerably tighter than the old ones and very possibly within specs

I don't have the tool for measuring the bore however you can again, get an idea measuring between the bore and piston itself to see how worn it is.. These engines will run darn near forever if even slightly maintained

* An old Dodge slant six engine I acquired from a friend would blow 5 quarts of oil out the dip stick tube within 10 miles or so.
Pulled the motor, ring end gap was 1/4". Replaced the rings (STOCK SIZE), (didn't even do a valve job) and it didn't leak / blow a drop of oil for years (BIL bought it). Compression was blowing past the rings, into the crankcase, then out the dip stick tube.
 

Scrubcadet10

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I would advise against honing with the crank in. Even though you're barely removing any material you need to clean your cylinder and inside of crankcase with soapy water to get out all the small honing residue. IF you do hone with the crank in, be careful not to stroke down too deep and hit the crank pin. You can possibly shatter the stones (if you use a 3 stone hone, not a ball hone) and cause more damage.
Or are you taking to a machine shop?
 
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Mack..... Briggs says not to hone a Kool Bore..... Just clean well .......... There is a special coating in the bore....

Regular sized rings are what you want...... Briggs also says if a honing is required then use aluminum stones.....

Briggs does make oversized rings, but you have to buy a piston to match then a bore job......
 

rwomack

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Mack..... Briggs says not to hone a Kool Bore..... Just clean well .......... There is a special coating in the bore....

Regular sized rings are what you want...... Briggs also says if a honing is required then use aluminum stones.....

Briggs does make oversized rings, but you have to buy a piston to match then a bore job......

GREAT info guys. Sounds like I need to at least pull the rod off the crank, pull piston out, and check the cylinder wall and ring gap. I’ll send pics of it when I get it apart. Btw, I’m OCD :) is there a torque table for everything going back?
 
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Yes there is a table ..... Google Briggs specs and a PDF site will pop up.... Click on that one ....

Like I said before I can look up the parts for you.........
 

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Mack..... Briggs says not to hone a Kool Bore..... Just clean well .......... There is a special coating in the bore....

Regular sized rings are what you want...... Briggs also says if a honing is required then use aluminum stones.....

Briggs does make oversized rings, but you have to buy a piston to match then a bore job......

Interesting...

Then, in this case, (per Briggs), just clean the cylinder (as the OP is likely NOT boring the engine-not worth it $ wise) and replace rings with stock rings.

No yanking the flywheel, crank, etc..
 

rwomack

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Interesting...

Then, in this case, (per Briggs), just clean the cylinder (as the OP is likely NOT boring the engine-not worth it $ wise) and replace rings with stock rings.

No yanking the flywheel, crank, etc..

Ok. What do you recommend cleaning cylinder wall with?
 
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