Cub Cadet with Briggs and Stratton motor

srwa

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Believe I "shelled" the engine this time. No compression,either cylinder. Valves don't move on #2.
 

Forest#2

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Sometimes you can tie a knot in the end of the strap and when wrapping leave the knot sticking up out of the first wrap so as you can keep the next wraps from immediately slipping. You can do some looking and find a place to tie the other end so as its secure as the flywheel is turned to take up the slack. The nylon strap will not stretch hardly any once the slack is removed for the torque wrench. On the old flywheels that have the cast fins just stick the first knot between the fins then start wrapping..
Your engine has the plastic bolt on fins so just remove them or leave them off until torqued.

Make sure both the crank and the flywheel taper is really clean. Use lacquer thinner on a rag and wipe clean several times. No lube at all on either.
 

TobyU

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A flywheel key on a riding mower shouldn't actually shear due to hitting something with the blade because the fact that it is belt driven allows enough slippage 98 times out of 100 that you will not shear a key.
In fact, no riding lawn mower or no more engine at all actually needs the key. They are not designed to actually hold anything in place but rather just a carryover design that is still being used for the assembly process to make sure they get the flagpole on in the correct position.
If the flywheel and the crankshaft is clean and dry and torque properly, the friction alone holds it far more than the key ever will especially on a Briggs which is a soft aluminum key.
It's kind of odd that Briggs uses a soft key and Kohler and Honda and others use a steel key.
Most the time when I'm riding lawn mower engine she is a key is because of a safety switch or someone turning the ignition switch on and off multiple times and the on-again/off again jerking from the ignition turning on and off causes the key to be sheared.

My biggest concern is did you set the valves with the Piston one half inch pass top dead center.
If you did not this could be your problem. They do not set like a automotive engine and they do also do not set like the color engines that said it top dead center. On the Briggs engines you have to get them to talk dead center of the compression stroke and then go down at least one half inch more.

The carburetor is kind of a moot point. Whether it's doing the right fuel delivery or not is irrelevant because all you have to do is put some gas in a spray bottle or use a can of carb cleaner spray and spray it right into the throat of the carburetor. If your timing, ignition, valve adjustment and everything else is mechanically adequate, then it will start and run as long as you give it a fuel source which is your carb spray.

I would try this first because I think you have something else going on besides a carburetor if it simply won't run.
 

bertsmobile1

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Not quite right there Toby
All of the Australian made ride ons drove the decks from the rear , even the front engined ones
So akin to ZTR's when the deck it something and got pushed back, the belt tension was reduced and the belt does in fact reduce.
This is also what they all use standard polly belts and not the very expensive kevlar ones that all USA mowers need.
Conversely when USA made tractor style mowers hit something and the deck is pushed back the belt tightens so it either snaps or stalls the engine
Got dozens of Greenfield & Cox mowers in my run plus the 8 I lend out when I get overwhelmed and not a single one has ever broken a belt in fact most of them are sill running the original standard unwrapped polly belt that I fitted near a decade ago .
 

Forest#2

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You say:
Believe I "shelled" the engine this time. No compression,either cylinder. Valves don't move on #2.

Which engine and what did you do or not do to cause Murphy to appear??????????
 

srwa

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Pulled the # 1 head, exhaust push rod on # 1 cylinder is nowhere to be found, its gone....and its steel, intake is aluminum.

B & S Intek VTwin 23 hp. mod.445577-0499-E

Do believe the last time I ran this beast I had not torqued the fly wheel down enough. Made a terrible sound before it quit. Will be removing engine from tractor to work bench.

Not gonna like what I'm going to find.
 

Forest#2

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Two engines with flywheel not torqued, HMMMMMMM,

but I doubt that flywheel caused the push rod to go into the crankcase area.
I would probably try to use a small magnet and see if the push rod can be recovered before taking the engine apart, but both cylinders had no compression and push rods not moving any on one cylinder.
Your descriptions sounds like the inspection is going to be sadness.

Good luck to Ya.
 

srwa

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Well, I'M a practicing brain surgeon & professional solitare player. Thought I'd "branch" out into another profession. U know, something to fall back on.

Will be in touch.
 

TobyU

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Not quite right there Toby
All of the Australian made ride ons drove the decks from the rear , even the front engined ones
So akin to ZTR's when the deck it something and got pushed back, the belt tension was reduced and the belt does in fact reduce.
This is also what they all use standard polly belts and not the very expensive kevlar ones that all USA mowers need.
Conversely when USA made tractor style mowers hit something and the deck is pushed back the belt tightens so it either snaps or stalls the engine
Got dozens of Greenfield & Cox mowers in my run plus the 8 I lend out when I get overwhelmed and not a single one has ever broken a belt in fact most of them are sill running the original standard unwrapped polly belt that I fitted near a decade ago .
I'm not sure what you're talking about not being quite right.
I know nothing about Australian mowers so I was making a generalization about riding lawn mowers in the US.
I'm not sure what belt type has to do with much of anything as they only use the coded belts here because they are a clutched application and it's supposed to make the belt last longer than a standard rubber style automotive v belt and possibly prevent it sticking when it shouldn't.

My comments were that it's very rare to have a sheared flywheel key on a riding lawn mower and I will stick by that comment at least for the most common Briggs & stratton, Tecumseh, Kawasaki engines in the US over the past 35 years.
We get very, very few Hondas on riders but I would say those are probably the same.
I have seen riders and personally hit lots of things with riding mower blades enough to bend them in a 90° angle like hitting Giant roots, bricks, or even a four-way lug wrench I once ran over and none of them ever harmed the engine in any way.
They rarely even stall the engine they just alter its speed for a split second or the blade locks up and starts to burn the belt.
The deck normally doesn't hit anything and there's not a lot of moving around at all even when the blade does hit something. Very rarely do any of these belts snap even from hitting something.
They only snap when they are so old and worn out that they are cracked in multiple places where you could probably wiggle him a few times and pull them apart with two people.

And all of my experiences with them even if the belt does get stopped by the blade hitting something etc and even if the belt is tight around the pulley, it only goes around the engine pulley barely halfway and it doesn't have enough friction to stop the crankshaft in its place and allow them inertia and momentum from the flywheel to keep going and share the key. The crankshaft pulley at the belt continues to move some so the key way is just fine.
On push mowers it's completely different because there is no belt to slip on the vast majority of them so they often damage flywheel keys but actually they more commonly than the crankshaft and bend the blade and damage the blade adapter.
I would estimate that for every 10 push mowers I get in with a blade strike a little under two have a damaged flywheel key and the rest have other issues but the key is just fine.
 

TobyU

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Pulled the # 1 head, exhaust push rod on # 1 cylinder is nowhere to be found, its gone....and its steel, intake is aluminum.

B & S Intek VTwin 23 hp. mod.445577-0499-E

Do believe the last time I ran this beast I had not torqued the fly wheel down enough. Made a terrible sound before it quit. Will be removing engine from tractor to work bench.

Not gonna like what I'm going to find.
Ah the infamous missing push rod. It happens quite often on this engine.
Normally it's from a slipped valve guide that caused the push rod to bend and pop off in the first place but it can happen without any actual head damage but always be cautious and trying to repair it because normally there is a reason to push rod bent and disappeared in the first place.
It will be bent in an S shape and inside your crankcase.
Use a bright flashlight and a small magnetic pickup tool and you might be able to reach in there and find it but I've never been that lucky well maybe once.

I have repaired a number of these, once even and a guy's backyard while he watched.
It only takes about 12 minutes to pull the engine from the machine and then you should drain the oil out of it so it won't make as much of a mess.
I think there's 13 bolts that hold the base plate on.
So you should clean all that up really well or blow it off with compressed air or a good stiff brush and take the bottom off and you'll be able to get the push right out of there..
Then you can look around and see if there's any damage which there probably won't be just make sure there's no other metal pieces and they're floating around or whatever. I like to run a magnet around.
And then you can put it back together but be cautious...
You have to pull the 35/16 bolts off of the oil pump cover and take the oil pump gear out before putting this base plate back on are you risk a great chance of jamming up the oil pump by it not lining up and then you will have no lubrication and once you start and run it it will lock up and snap a rod in about 1 minute or two.
Once you have the bottom sump back on and torque down with a new gasket preferably but if the old one doesn't come apart too badly you can clean it and use some RTV anywhere it rips or a thin smear around it then, you can drop the oil pump gear and drive shaft back into place and put the flat metal cover back on.

Now you have to fix whatever the problem was the first place which is probably a slip is exhaust valve guide from overheating because that head probably had a lot of grease or grime or grass or nest build up on it.

You don't have to replace a head even though that's the official fix for a slip valve guide and pop exhaust valve seats and I can almost guarantee that after I fix one it will be stronger than the original was or the new one you can buy.

You have to put some rope or something in the cylinder and slightly rotate the Piston up to touch it to push to keep the valves mostly closed and then take the valve stem spring retainers and keepers and spring off of that valve.
Then you were really see how the guy is pushed out and why the rocker arm can't push that one down as far as the other one but you get also inspect this before you take anything apart by pushing with your thumb and looking with a bright flashlight.

Then you have to clean it up really well, I prefer carb cleaner to get all the oil off of it, and then I like to use red loctite even though it might not make any difference, it makes me feel better.
So I slather it with a good amount of red loctite but make sure I keep the lock tight off of the actual valve stem and then I drive it back into it's approximate proper position by tapping it with a hammer..
It won't take much because they're not very tight which is the problem to begin with..
You have to make sure you don't go too far but you can kind of gauge it from the other one or even look at the other head.
Then the key is you have to stake it.
You can even use some old school machine shop ideas and you could drill it and pin it but that's probably not necessary.
Staking involves using a punch or I prefer to use a number two Roberts square Drive bit and go around like 10:00 position 12:00 6:00 3:00 9:00 and then do the other ones in the middle of those and stake it with a hammer and your bit so you're pushing into the aluminum pushing it towards the valve guide so it's tightening it up.
You kind of have to get good at it and do it just the right position but it is easier on a valve guide than it is on a valve seat but once you do all this and the lock type probably helps, I've never had one move again.
So then you've got the engine back together and you've got the head fixed that was the offender in the first place so now you just have to put the new push rod in unless you're crazy enough to hammer it back into place and get it mostly straight which can be done but I don't recommend it.
Then you have to turn the engine over to get it on top dead center of the compression stroke and then turn it until the Piston goes down one half inch past that point and then you have to adjust both push rods which is kind of a pain in the butt on the bricks because it takes three or four times to get them just right.

Then you put the valve covers back on and you're done.
I always Mount the engine back to the machine after I get the base plate back on and I do the valve guide repair and adjust the valves with it on the mower.
It's really only about an hour and 15 minutes start to finish but that's when you have all the tools already out and ready to go because you've done it many times.
 
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