Flywheel stuck solid on crankshaft

[1964johnr]

I have a Stihl MS 211/c from 2010 and am stripping it down to look for a possible crankshaft seals/bearings problem or a split intake hose. It was all going well until I came to the flywheel. The nut was stubborn, but I eventually cracked it, but the flywheel is stuck solid. I have used the method of keeping the nut on the threads of the crankshaft to protect them and then hitting it with a hammer and centerpunch, but it just wouldn't budge. I heated the metal with a hair dryer, but still no joy. Has anyone any ideas, or will I need to find an appropriate puller to buy?

[luap]

With the nut on the crank threads, use a pry bar or large screwdriver to put some upper pressure on the flywheel, then smartly rap the flywheel nut with a brass or copper hammer. Don't go crazy prying on a thin section of the flywheel You tube Taryl fixes all demonstrates this. You can also use an air hammer to rap against the crank shaft. 

[sawguy21]

Ensure you are not resting the saw on the clutch while doing this.

[1964johnr]

Thanks for the replies guys. I'll give it a go and see how we go. Perhaps the extra upwards  pressure under the flywheel with a prizing tool will do the trick. I'll let you know.

[Air Lad]

Gently does it
If one gets too heavy handed other problems can develop
Heat and not centre punch but a larger diameter object ( I use a 3/8 socket extension bar )and a snapping shot from a medium ball pein hammer
No substitute would be as good as the genuine tool for the job but
And be mindful of the clutch on the other side

[1964johnr]

Thanks for all the info. I found it all very useful. I protected the clutch with some old rag and gave it a fairly hard whack with a wide socket extention a couple of times and off it came. I'm thinking that because it was stuck, it needed a little more force (but not to much) .The wider socket extention seemed to work where as the punch didn't. Now for the cylinder removal. The crunching noise I had when the engine was running makes me think perhaps the crankshaft bearings are disintigrating, but I guess it could also be a split inlet hose, scored piston, ( there were a few vertical light scoring marks when I inspected through the muffler port), scored piston rings or leaking crankshaft seals. Wow, that sounds like I know what i'm talking about, in reality this is the first time I have stripped a saw completely down to the bare bones. I have a few more questions that you will all be able to answer i'm sure.

1. Any ideas for removing bearings from the crankshaft without a specialist puller?
2. Do I need a specific sealer for putting the cylinder sections back together. 
3. What oil do I rub on the piston before putting it back together? 2 stroke?
4. I have been looking online at replacement parts and it seems that complete engine units and cylinder/piston units seem to be much cheaper in America than over here in London so I'm thinking of importing whatever I need. Does anyone know a good stockist of aftermarket engine parts?
Thanks for your help with this project. John.

[luap]

I am not familiar with this specific saw but can give an opinion. I did a Husqvarna and used a complete crankshaft kit and it came with bearings already assembled on shaft. I did have to assemble piston wrist pin and piston and rings. Any oil is better than no oil for assembly but auto parts stores sell an assembly lube. Otherwise I have used an oil treatment oil like STP that is thick and tacky and stays put on the metal surfaces. Mating metal surfaces were assembled dry with appropriate gaskets. The only time I used a sealant on a gasket surface if it was in an awkward position and needed it to stay in place until the bolts were started.
Small engine warehouse and jacks small engines are two places I have bought parts from.

[dougand3]

You need a gasket maker/sealer resistant to gas/oil.  Permatex Motoseal, Threebond 1194, Loctite 518, Yamabond, Dirko Red are some.
Any oil will do putting piston in. 2 cycle, tranny fluid, 30 wt.
AM parts are cheapest coming from China. Check ebay. I assume they ship to UK. Maybe taxes make expensive?

[joe_indi]

Thanks for all the info. I found it all very useful. I protected the clutch with some old rag and gave it a fairly hard whack with a wide socket extention a couple of times and off it came. I'm thinking that because it was stuck, it needed a little more force (but not to much) .The wider socket extention seemed to work where as the punch didn't. Now for the cylinder removal. The crunching noise I had when the engine was running makes me think perhaps the crankshaft bearings are disintigrating, but I guess it could also be a split inlet hose, scored piston, ( there were a few vertical light scoring marks when I inspected through the muffler port), scored piston rings or leaking crankshaft seals. Wow, that sounds like I know what i'm talking about, in reality this is the first time I have stripped a saw completely down to the bare bones. I have a few more questions that you will all be able to answer i'm sure.

1. Any ideas for removing bearings from the crankshaft without a specialist puller?
2. Do I need a specific sealer for putting the cylinder sections back together.
3. What oil do I rub on the piston before putting it back together? 2 stroke?
4. I have been looking online at replacement parts and it seems that complete engine units and cylinder/piston units seem to be much cheaper in America than over here in London so I'm thinking of importing whatever I need. Does anyone know a good stockist of aftermarket engine parts?
Thanks for your help with this project. John.

1. I use a steel rod and hammer to tap it out
2. Any liquid gasket sealant that is not affected by fuel is good enough
3. 2 Stroke oil, since you have it. I use it in a 1:1 mix with fuel
Bearings are 6202 C3 . And they come on most saws

[1964johnr]

Thanks for the replies. They have all been very helpfull. I got stuck for a while trying to remove the cylinder from the crank case until I realised that the throttle linkage was stopping me from removing it. Once I removed the saw handle and the linkage, it came away. I was expecting to find worn bearings because of the strange sounds coming from the saw when I pulled it over. I was wrong. Bearings looked good, seals looked fine. It was only when I withdrew the piston from the cylinder that I found the isuue. The crown  of the piston and the inside of the cylinder at the top were covered in carbon deposits. The top of the piston is completely black instead of shiny silver. I have watched a couple of videos on how to remove the carbon from the piston, but i'm not sure how I am going to remove it from inside the cylinder.
I may need to buy an AM cylinder. Apparently, this layer of carbon distorts the compression to the point where 'Knocking' occurs, which accounts for the strange noises I was getting.

[motzingg]

The bearings on the crankshaft are best removed with this type of puller, i use mine in an arbor press but if you buy the kit it will come with a block and draw-rod arrangement that will push the crank out:  

https://www.harborfreight.com/bearing-separator-and-puller-set-62593.html

The puller bar that is shown in that kit will also work to remove a lot of flywheels by using m6 or m8 bolts.

If the bearings are fine and it is a 'clamshell' style case which i'm guessing it is, I would leave them.  Pulling them off and pressing them on is just more opportunities for beginner mistakes.  I would still replace the shaft seals though, always nice to do them when an engine is apart. I use a lot of AM china junk parts but this is one thing that i spend the money on OEM and buy good ones.

Use liberal application of two stroke oil on the piston when you slide it in, as well as on the bearings.  

I like the 'motoseal' aka 'yamabond' aka 'threebond 1194' style goop, use it sparingly, just enough for a thin even smear. Dont get oil on the goop and don't get goop in the engine.  I use the 'engine assembly lube' on the wrist pin bearing, big end bearing and crank bearings, but its more because i'm anal and superstitious, than it is for any practical purpose. 

Using the wrong/too much goop caused this on a leaf blower i recently rebuilt:


 


 


As far as the carbon goes, put the spark plug back in and dump some acetone in there (you can use MEK too but that stuff nasty).  Give it a few days to loosen up and go in there with a paint stick or tounge depressor and scrape away as much as you can get.

When you rebuild the saw make sure that your tuning or your oil mix ratio or something else isn't contributing to the oil deposits.  Its not normal for a two stroke engine properly tuned and using modern oil to coke up like that.  

[realzed]

I think if I had one down this far - I would just change out both the seals and bearings.. Just because... 
Its basically pretty much as 'torn down' as it can get at this point anyway - so why not ensure everything is perfect while you're in there for the peace of mind if for no other reason and small extra cost involved in doing so.. IMHO  

[luap]

I think if I had one down this far - I would just change out both the seals and bearings.. Just because...
Its basically pretty much as 'torn down' as it can get at this point anyway - so why not ensure everything is perfect while you're in there for the peace of mind if for no other reason and small extra cost involved in doing so.. IMHO  

I agree. This is a basic principle for any kind of equipment overhaul. If hard to access, replace it. if easy to replace then leave it alone. Also individual parts bought piecemeal can cost more than a rebuild kit. In the case of your chainsaw you have run it to the point of breakdown but that is not a good  policy to follow with more costly industrial equipment.