Forget the piston stop

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So the basis of your who's chest can be pushed out further side of the argument is removing small stationary engine 4 stroke internal pawl cupped starter flywheels versus chainsaw flywheels that are the subject of choice?
From my background- a 20oz steel hammer is a tool for finishings and or apprentices and many plastic/leather/brass/aluminium faced hammers will deliver just as much- or a whole lot more- (depending on head weight) striking force.
Nobody is doubting you might work on 40 pieces of equipment a week- most urban folk that know little about small engines, yet own engine powered equipment, need someone to do the basics and keep their garden tools running. Personally I try to avoid the consumer pile of line trimmers, but if one needed fixed- I am fairly sure I can handle it, as can a lot of other folk that comment on posts here- at the end of the day, they are all powered by fairly simple forms of engine.
Don't work on four strokes unless you include Stihl 4 Mix . So, you don't actually do any of this either. Why are you posting ?

It doesn't matter whether it is an internal pawl with a cup or an external pawl to bust. If the nut does not have a skirt you are still going to have to get that flywheel popped off the taper. Some are tight enough that they sound like a shot when they break loose. You can use a puller which you pretty much have to on a large saw, or you can hold the flywheel with a large pair of channel locks and hit a deep socket against the loose nut with a hammer if it has a skirt. If you don't have a puller and the nut doesn't have a skirt then you either need another hand or somebody to hold something for you to tap. That aluminum cup or the pawls themselves if they are external don't like to be hit with a hammer.

Maybe somebody could learn something that would save them some trouble down the road.
 
:popcorn2: Your shop--run it how you want--Old cat mechanic--Love old stuff--LT-37 Johnson outboards-old saws-1950 F-3 ford truck-coleman stove-lantern-all appliances-plumbing-Briggs and Straton washing machine engines.You learn things-slow and steady. A lot of people rip and run--and reap all kinds of benefits!!! Lets go finish putting carb kit in holley 94 carb off 1950 flathead v8!!!

I just pulled the intake and exhaust manifold off my 81 F-150 300 straight six between posting on this stupid forum . Ticking noise .Every professional auto mechanic says it was a cracked exhaust manifold on the back side, but if it is it's invisible. One of the exhaust ports is coated black, and the rest are relatively clean. I took the wires off one by one and they all caused a skip. But, I'm afraid I've got a valve problem.
 
Don't work on four strokes unless you include Stihl 4 Mix . So, you don't actually do any of this either. Why are you posting ?

It doesn't matter whether it is an internal pawl with a cup or an external pawl to bust. If the nut does not have a skirt you are still going to have to get that flywheel popped off the taper. Some are tight enough that they sound like a shot when they break loose. You can use a puller which you pretty much have to on a large saw, or you can hold the flywheel with a large pair of channel locks and hit a deep socket against the loose nut with a hammer if it has a skirt. If you don't have a puller and the nut doesn't have a skirt then you either need another hand or somebody to hold something for you to tap. That aluminum cup or the pawls themselves if they are external don't like to be hit with a hammer.

Maybe somebody could learn something that would save them some trouble down the road.

In my opinion- no you dont need anything more than the hammer to work any scenario on a saw flywheel- regardless of the nut in question.
I have never found the need to hold flywheels with channel lock pliers- but if it works for you- it works for you.
If starter pawls are covering access to the flywheel keeper nut- remove the pawls.

Funny, if folk have a differing way than yours to come to the same conclusion in the end- they seem to get branded as people who can type of their experience- but in your opinion have no experience.
Thats okay, you are free to think how you think- but passing opinion on folk you have no clue about their past nor present experiences is a tad petty and on past experience here, you are the type of guy not to know when to let an argument slide- like the energiser bunny in Terrier form- you just keep ankle nipping.
So I will bow out and let you have your back and forth chest puffing with others. No skin off of my nose.
 
In my opinion- no you dont need anything more than the hammer to work any scenario on a saw flywheel- regardless of the nut in question.
I have never found the need to hold flywheels with channel lock pliers- but if it works for you- it works for you.
If starter pawls are covering access to the flywheel keeper nut- remove the pawls.

Funny, if folk have a differing way than yours to come to the same conclusion in the end- they seem to get branded as people who can type of their experience- but in your opinion have no experience.
Thats okay, you are free to think how you think- but passing opinion on folk you have no clue about their past nor present experiences is a tad petty and on past experience here, you are the type of guy not to know when to let an argument slide- like the energiser bunny in Terrier form- you just keep ankle nipping.
So I will bow out and let you have your back and forth chest puffing with others. No skin off of my nose.
I'm not against the use of pullers for things like dirt bike flywheels or snowmobile clutches, but for a chainsaw, no way is it needed.
Even in the case of a sled or a bike you end up tapping the puller with a hammer to get it to break free in many cases anyways.
 
In my opinion- no you dont need anything more than the hammer to work any scenario on a saw flywheel- regardless of the nut in question.
I have never found the need to hold flywheels with channel lock pliers- but if it works for you- it works for you.
If starter pawls are covering access to the flywheel keeper nut- remove the pawls.

Funny, if folk have a differing way than yours to come to the same conclusion in the end- they seem to get branded as people who can type of their experience- but in your opinion have no experience.
Thats okay, you are free to think how you think- but passing opinion on folk you have no clue about their past nor present experiences is a tad petty and on past experience here, you are the type of guy not to know when to let an argument slide- like the energiser bunny in Terrier form- you just keep ankle nipping.
So I will bow out and let you have your back and forth chest puffing with others. No skin off of my nose.
So, how do you hold them ? You have to have the weight of the saw up or you are just banging the other side of the crankshaft on the bench. You can hold it up with your fingers on a small saw, but there is a point where I can't anyway.

Well, I just asked how you use a 1/4 inch impact to get the flywheel popped off the taper. Post 35 I guess, but I don't have one. Whatever works for you to get the flywheel loose works for you.
 
I'm not against the use of pullers for things like dirt bike flywheels or snowmobile clutches, but for a chainsaw, no way is it needed.
Even in the case of a sled or a bike you end up tapping the puller with a hammer to get it to break free in many cases anyways.
In severe cases on sleds & bikes a torch may be warranted . I actually have used the hydraulic action of a high pressure grease gun to break free a clutch on a Yamaha sled (SSR Pro Mod ) . Broke two pullers & even a torch & water never broke it free . The grease gun however did . Anyhow , have used a brass hammer as advised in post #35 in most saw applications , although I have every puller imaginable , & when warranted I use them accordingly .
 
Holy mackerel, how did this thread get so aggressive?
There is an old saying that "an ounce of jar is worth a pound of pull". For saw flywheels I combine both, nip up a puller firmly and tap it with my Thor branded copper hammer from my apprenticeship days in 70s and off she pops, no load, no probs
 
Impact to loosen, puller to remove FW if I have the right one. If I’m lazy with larger equipment I’ll zip the FW nut back on with the impact. If you use one enough you get a good idea by the rpm, feel and sound.
I once made a bad mistake taking out a 4mm screw on a 084 oiler with a 1/4 impact. Had the direction wrong and snapped off the head with the threads left in the case. Not a desirable outcome on my precious 84.
Taught me to check direction at least twice
 
I just pulled the intake and exhaust manifold off my 81 F-150 300 straight six between posting on this stupid forum . Ticking noise .Every professional auto mechanic says it was a cracked exhaust manifold on the back side, but if it is it's invisible. One of the exhaust ports is coated black, and the rest are relatively clean. I took the wires off one by one and they all caused a skip. But, I'm afraid I've got a valve problem.
Check the manifold face for warpage if you pulled it already, the bolts/studs can be stretched, check pushrods rockers and cam lobes and perform a leak down/compression test. Have even seen them with sagging motor mounts and over filled with oil push oil past the #6 rings. A sharp smack using a brass hammer can pop a flywheel off but if you have ever removed a flywheel with the pickup or coil under under it you know you need a proper puller because that joker is not budging without one. Even when using the correct puller on a flywheel that has the magnets on the inside it will feel like your going to break the puller bolts or pull the threads out... that sht can be scary when you get a stubborn one.
 
In severe cases on sleds & bikes a torch may be warranted . I actually have used the hydraulic action of a high pressure grease gun to break free a clutch on a Yamaha sled (SSR Pro Mod ) . Broke two pullers & even a torch & water never broke it free . The grease gun however did . Anyhow , have used a brass hammer as advised in post #35 in most saw applications , although I have every puller imaginable , & when warranted I use them accordingly .

.
Another trick for removing sled clutches is the frozen water method.

With the small crankshaft on a saw there just isn't the holding force of a sled crank shaft so all these tricks are not needed.

Using a brass hammer isn't a bad idea. I actually have an old school copper hammer that was my tool and die maker grandfathers
 
Check the manifold face for warpage if you pulled it already, the bolts/studs can be stretched, check pushrods rockers and cam lobes and perform a leak down/compression test. Have even seen them with sagging motor mounts and over filled with oil push oil past the #6 rings. A sharp smack using a brass hammer can pop a flywheel off but if you have ever removed a flywheel with the pickup or coil under under it you know you need a proper puller because that joker is not budging without one. Even when using the correct puller on a flywheel that has the magnets on the inside it will feel like your going to break the puller bolts or pull the threads out... that sht can be scary when you get a stubborn one.
That's a good point. I've never removed a saw flywheel with the coil under the flywheel.
 
Check the manifold face for warpage if you pulled it already, the bolts/studs can be stretched, check pushrods rockers and cam lobes and perform a leak down/compression test. Have even seen them with sagging motor mounts and over filled with oil push oil past the #6 rings. A sharp smack using a brass hammer can pop a flywheel off but if you have ever removed a flywheel with the pickup or coil under under it you know you need a proper puller because that joker is not budging without one. Even when using the correct puller on a flywheel that has the magnets on the inside it will feel like your going to break the puller bolts or pull the threads out... that sht can be scary when you get a stubborn one.


That exhaust port with all the extra cake is what has me scratching my head. I don't see any sign of a leak on the manifold. I had a rocker stud break on this a few years ago. I'm going to pull the valve cover this morning and check compression on that cylinder.
I bought a new exhaust manifold, but I hate to put it on and then have to take the head off anyway.


IMG_0705.JPG
 
That exhaust port with all the extra cake is what has me scratching my head. I don't see any sign of a leak on the manifold. I had a rocker stud break on this a few years ago. I'm going to pull the valve cover this morning and check compression on that cylinder.
I bought a new exhaust manifold, but I hate to put it on and then have to take the head off anyway.


View attachment 1037466
If compression is decent and oil consumption is minimal I'd guess valve stem seals or possibly a guide, I would even look in the intake to see if the pcv breather is running oil into that cylinder.
 
If compression is decent and oil consumption is minimal I'd guess valve stem seals or possibly a guide, I would even look in the intake to see if the pcv breather is running oil into that cylinder.
Compression is 150, according to my gauge anyway. Sounds like an exhaust leak to me, I just can't see where. Then I saw that exhaust port which sort of stood out as different. There are no pieces under the valve cover and everything looks the same through the springs, no cracks that I can see.

But, this is way out of my lane. I have a new exhaust manifold and new gaskets should be at O'reillys at 1:30 If it still does it I'm going to turn the radio up.
 
Compression is 150, according to my gauge anyway. Sounds like an exhaust leak to me, I just can't see where. Then I saw that exhaust port which sort of stood out as different. There are no pieces under the valve cover and everything looks the same through the springs, no cracks that I can see.

But, this is way out of my lane. I have a new exhaust manifold and new gaskets should be at O'reillys at 1:30 If it still does it I'm going to turn the radio up.
measure the range of motion both rocker arms travel then compare it to the adjacent rock movements. This can show you a bent push rod or worn cam lobe. Valve stem seals are not difficult to replace and are inexpensive. 150 psi is acceptable compression, is it within 10 psi of the others? With it that far apart I would slide new stem seals in, clean the valve cover, test and clean the pcv and replace the exhaust manifold bolts/studs for the effected runners. Does the egr feed that cylinder its majority of flow and open/close properly even when not commanded.
 
Everyone loves a nice pair of jugs, everyone including their owners :cool:

You should all go dry off now.

OK. For some of you out there that have never done this before. Most all saws have some kind of cup on the flywheel that holds the pawls or however that manufacturer wanted to engage the starter mechanism with the flywheel. It is recessed. This is a simple matter if the nut that holds the flywheel has a skirt, which most of them do anymore. But, there are many saws where the nut that holds the flywheel is just a plain old nut with no flange.
So, you can try to center a hammer in the middle of the cup and not miss and break the damn thing. Or, you can get somebody to hold a piece of round or square steel bar maybe three inches long, enough you don't get your fingers banged.
Just picture it in your mind. A flywheel tightened down on the crank shaft held by a nut with no flange.
It is easy if you have somebody to hit the piece of steel while you hold the steel in one hand and the flywheel in the other.
You ^ make stuff way too complicated. Get a socket and if it's too deep put a nut in it then go grab a BFH or tiny one. Just don't mash anything.

K.I.S.S.
Personally I have a teeny tiny hammer for engines and a big gun 😀
Metal piston stops suck for removing parts from an engine, period. They ruin pistons.
Now go cut something not someone you hooligans.
 
Everyone loves a nice pair of jugs, everyone including their owners :cool:

You should all go dry off now.


You ^ make stuff way too complicated. Get a socket and if it's too deep put a nut in it then go grab a BFH or tiny one. Just don't mash anything.

K.I.S.S.
Personally I have a teeny tiny hammer for engines and a big gun 😀
Metal piston stops suck for removing parts from an engine, period. They ruin pistons.
Now go cut something not someone you hooligans.
I've seen the cups @zero is talking about, but only on a Lawnboy Duraforce motor. I don't recall a chainsaw having such a cup. My memory could be faulty though. Regardless I've never had a problem removing a Duraforce flywheel with the cup.
 
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