This Will Destroy Your 2 Stroke Engine EVERY TIME!
One of the most common mistakes I see people make when rebuilding small engines is incorrect installation of the crankshaft oil seals. This mistake will eventually lead to a destroyed 2 stroke engine every time!
In this video I show the correct method on how to install 2 stroke oil seals, what tools you’ll need (you’ll likely already have at home!) and the pitfalls you must avoid making to install oil seals correctly. It doesn’t matter if you are repairing a Honda Leafblower or Stihl chainsaw, a husqvarna lawn mower or echo weed eater; regardless of what small engine you’re repairing, the process is the same every time!
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#2stroke #stihl #Husqvarna #smallenginerepair #carburetor #chainsawman
00:00 This will seize your 2 stroke engine!
00:15 What is an oil seal?
00:26 How to do a vacuum test
01:05 Avoid prolapsing an oil seal
01:41 Caulking nozzle for oil seal installation
02:20 Using an aluminum can to install oil seals
02:50 Using an OEM oil seal sleeve
03:10 Machining an oil seal sleeve
03:45 How to install a 2 stroke oil seal
05:00 How to adjust a carburetor
If this video helped you, please consider clicking on the THANKS button above to support my channel 🙌
The hell are you talking about? 2 stroke engines don’t have crankcase oil, they get all piling from their fuel.
@@308dad8 if you had asked more politely I’d explain your mistake to you..
Great video as always 👍🏻
@@IndianaDoug thanks mate :)
I have thrown many away because I didn't know about that
You know as a disabled vet I've been going through different Stihl certifications to work on warranty work. I've learned so much from this channel I wanted to thank you for your time you put into these. I could probably ask you 100 questions regarding chain saws and weed eaters. My problem is I get to frustrated to easily, I like perfection the 1st time around but learned really quick that's not how it goes. Again thank you.
Thanks for the kind words, I’m glad you enjoy my channel :) yes, taking a step back and not getting frustrated is a learnt skill for many of us, myself included!
Thank you for your service. I’ve worked on many different kinds of engines, car engines lawn equipment. Just keep after it before you know it you’ll be the go to Guy.
@@RustyClam 👍
Sometimes you gotta bang your head a little to find the right way
Thank you for your service, I’m sorry that the spineless leaders of our country aren’t serving you the way you served the country.
Thanks, I learn as much a I can from videos like yours about maintaining my equipment. I haven’t run into anyone talking about this preventive maintenance, so thanks. It should save many small engines from an early failure! Good job, mate! From the US.
Thanks for the kind words :) glad you enjoyed the video!
When I worked on specialized equipment, we used green Loctite 609 on the outer race of bearings. It held the bearing in place and acted as a seal as well. These were larger shaft bearings. One good thing about 609 is it's anerobic and it cures fairly quickly.
I like and use 609 :) thanks for sharing!
@@VintageEngineRepairs I like you, I like to be man handled.
Great tip. Most people don't even know how to pressure and vacuum test, or that it is even needed. Merry Christmas!
Thanks Mike! I agree, and some others that do know are too lazy to do one LOL
I'm getting ready to replace the seals on a LawnBoy mower...what a great tip! Thanks! Subbed
Glad it helped :)
Well done Tom and love the installation tips and manufacturing your own installation tools buddy.
Thanks Wayne! Much appreciated :)
Greetings from the other side of the world, rural Arkansas to be exact. Wonderful video on perhaps the most neglected aspect of two stroke engines. In fact, this problem was my introduction to chainsaw repair and the start of a great hobby. It's rewarding to see someone else using Dirko on the outer edge instead of grease, as most do. Dirko acts as a lubricant when wet and forms a seal much better than grease when dry. One thing I might add: a twisted tube of thin, flexible plastic, such as the sturdy plastic bags that dog food or cat litter come in, can also be used to get the seal over ledges safely, and it's a universal fit. Thanks, Tom!
Thanks for sharing another sleeve idea! That’s cool :) yep; I never use grease on the outer lip; some seals don’t have a tight fit, it helps keep them in sometimes too!
Excellent tip for future reference! While I’m not rebuilding a chainsaw, I’ll be rebuilding the engine on my 1978 LawnBoy 5277. Pretty much the same deal though with it being a 2 stroke. But if I ever need to reseal the engines on my chainsaw, trimmers, or blower, I’ll definitely keep this tip filed away in the back of my mind.
Awesome, glad you enjoyed it!!
Using grease in the cavity of the gator spring will keep the spring in place upon impact with a seal driver , used them every time when replacing crank,cam, and heavy truck wheel seals, never a problem after 45 years ,roger cheers from Canada
Thanks for sharing!
Great info Tom, never used the caulk tip trick but will now 👍
Great to hear Al!
Love it. It's tips like these that makes the difference between a good tradesman and a great tradesman.
Thanks for watching, glad you enjoyed it!
Awesome tip, thanks for sharing. Ontario, Canada.
You’re welcome, thank you!
That’s a great tip. I was thinking of using a socket . I do residential siding so I have lots of silicone sitting around
Perfect :) glad it helped!
I enjoy making my own tools. Thanks Tom
Right on Bruce!
Thanks for sharing these simple tips.
You’re welcome :)
Wow. An excellent video that wasn't "ethanol scaremongering". Thumbs up!
Thank you :) thankfully we don’t have ethanol here so I couldn’t do an ethanol video anyway 🤣👍
no wonder your subscribers are going up Tom, putting out good tips like this one 👌👍
You’re very kind, thanks Nev!
Good video. I like the quality and finesse of your work
Thank you :)
It is hard, ..... to not like your videos when they are so informing. I hate watching them because I don't necessarily want to become a small engine repairman! :.))) Thanks, and have a pleasant 2024.
Haha thanks mate :)
Thank you for the most important information that I did not know about my saws. And that's going to save me a good deal of money !
Glad you enjoyed it 👍
The best oil seal insertion tool for me has always been a piece of xray film, used similar to the can but 100% safer. Plus you can inset it over the step to the bearing so that the seal moves in smoothly
Thanks for watching 👍👍
Amazing video ! Love the transition from oak tree garden to figure video demonstration. Nice to put a face, and accent as well, to the name as ive seen your comments before ! Well, not an oak, but from the big tree garden.
Thank you! Glad you enjoyed the video :)
Excellent explanation and advice.
Thank you !
Thanks for the great caulk tip.
You’re welcome!
Deserves a million likes. Great video.
Thanks for the kind words :)
Fantastic presentation. All the way around.
Thank you :)
Good info 👍 . Ive done the coke bottle on the clutch side befofe , works perfect
Awesome! Glad it resonated with you :) yep super handy isn’t it 👍👍
Thank you so much, I have a chainsaw that doesn’t work and I’m planning to see if I can fix it. I already know I would have made this mistake because I didn’t know about this.
Glad it helped you, that’s awesome!
Oh, that’s an excellent tip for getting seals over shoulders intact.
Glad you enjoyed it!
Super great info! everyone should also know, NEVER run the fuel tank dry. always stop and add fuel and take a break. sthil weedeater here 13 years 0 work or adjustments and I "hot rod abuse" my equipment.
Glad you enjoyed the video! It’s not a good idea to run them dry if you can avoid it :)
I have never heard this, what is the reason for not running til dry (aside from any trash in bottom of tank entering engine) ?
You create a (lean condition) each time you do this. it adds up to small amounts of wear that erode the cylinder walls. Iv been abusing 2 stroke equipment for over 20 years and had an old timer tell me this. Ive, never damaged a piston, After all if you run the engine dry each time, you run without oil for just a second, and it adds up. Just food for thought.
That's really useful info I really enjoy your chainsaw repair videos.
Thank you! Glad it resonated with you!
Are OEM parts hard to get in Australia? 3 series Husqvarna cylinders are hard to get in the UK, Meteor cylinders are available as are OEM imports from the US.@@VintageEngineRepairs
Na stihl parts are plentiful here, though Husqvarna have been horrifically difficult to get.
Great information! Thank you!🤩🤩
You’re welcome :)
Good tip Tom.
Thanks Pete !
Fantastic video!
Thanks Richard, much appreciated. I really enjoy your channel mate!
Super helpful!
Glad you enjoyed it :)
Excellent video.
Thank you 🙏
Thanks, Tom.
You’re welcome!
Excellent video
Thank you! Glad you enjoyed it :)
Genius! Trains with the brains.
Haha yes :)
Great video thank you.
You’re welcome :)
the sleeve on a NGK spark plug works on the Husqvarna. Caulking tube nozzle is fantastic.
Ha awesome, I didn’t know that re the plug sleeves!
I was certified to work on Stihl saws by the manufacturer and saw several unfortunate failures caused by owners who refused to read the owner's manual. One fellow removed the flywheel to change a chain (totally unnecessary) then put it back together improperly. Internal parts rubbed through the plastic casing and destroyed the automatic oiler. Saw was junked. Another ran the saw on straight gas and seized the piston. Saw several of those. It was not surprising that some users just refused to accept they were the problem, even though they refused to learn about the saws.
We need warning labels for everything now days! Thanks for sharing :)
BRILLIANT!
Glad you enjoyed it! :)
great video
Thanks :)
Great advice. Now I need to get my brother in law to make me some sleeves on his lathe.
Absolutely! Useful to have him as a resource haha
One could also 3D print a seal install tool, so long as they sufficiently sand/polish the OD. Layer lines wouldn't play nicely with the seal. Resin printing would make a very smooth install tool, but most of us don't have resin printers.
Yep! That would work; I’m sure. Best to use a file so you don’t get sanding grit stuck in the plastic :)
Yup, prolapsing a seal can be a pain in the butt!
Yes! So many don’t realise it too!
I know about the can, but not the caulk tip. Wonder if the industrial size tubes would fit. Great info.
Oooo!! I figured there must be larger tubes, but never seen one :)
@@VintageEngineRepairs if I find one I’ll let you know. Do you have a video about removing the seals?
Heat shrink tubing on the crank shaft works good also. There are many defiant sizes of tubes.
Interesting! I haven’t tried or heard of that before, thanks for sharing!
😂😂 wouldn't "defiant" heat shrink tubes refuse to fit? 😅😅😅
The caulking nozzle is a really good tip, all crank seals and any seal on a shaft it would work . MIG nozzle will do bigger shafts.
Thanks for the tip re mig nozzles! Glad you enjoyed the video!
fortunately not all saws have the stepped crankshaft problem like that stihl does. I do a lot of work on Jonsereds 49sp, 52, 70 and there is no difficulty at that point of seal installation, also do Homelite SXL/AO and 925 XL saws without a hitch. Prolapse can definitely happen but with some saws it is far less likely. I never use sealant on the outer seal surface unless there has been damage to the seal casting in the crankcase. Always test your installation for pressure and vacuum after finishing installation.
I’ve just had a look, the first one I searched (super XL) has a stepped crank and must have a sleeve. I can’t search them all, but I’d suggest proceeding with caution.
thank you, I have done several with no problems. Using a pop bottle piece of plastic as a sleeve to "shoehorn" the seal over the ledge can be useful but I have also found that using a seal driver that fits pretty snug on the crankshaft helps very much to prevent the rolling of the seal material, that dreaded prolapse, a small piece of tubing or pipe, metal or plastic really aids the process. Warming the seal material is of value too, allows the butyl or viton...which ever is used....to expand and conform to new shape. The key is to take your time and push by hand, avoid hammer blows or such when trying to get that seal over the sharp edge.@@VintageEngineRepairs
Wow... I wish we could all love our trade as much as this man does his. There is no person you want to hire more than a guy who is enthusiastic about his trade! Thebman machines his own little seal slipper oner thingy! 💪🏻 I subbed to the channel in that moment 😂. This video was art to me, cant wait to see and learn more! Thank you!
What a wonderful comment, I appreciate it more than you know :)
@@VintageEngineRepairs tis but the truth my friend 🙏
I used electrical shrink tubing over my valve stems to protect the seals during installation.
Interesting!
You can ether burn up a piston or do a simple vacuum and pressure test. Sometimes leaks show up with the vacuum test and sometimes the pressure test is needed, remember dimensions change with temperature. I’ve done hundreds of those with a piece of plastic bag or thin piece of plastic. I only used sealant a few times if the seat was questionable.
Thanks for watching and sharing. I have never had a seal that’s failed on pressure then hold on vacuum though.
@@VintageEngineRepairs I’ve had a few do it with rotation and a few stationary. From what I’ve heard it’s extremely rare to have one seal under vacuum and not under pressure and when it does happen it usually doesn’t affect the way the saw runs. I don’t know how true that is but I was just use to doing all the checks and making sure whatever I worked on was a 100% before I released it. I was a heavy equipment tech for years and avoided these things as much as I could but had some clients who had a bunch of old saws, big ones, and wouldn’t shut up about needing them fixed. I’d just do the basic stuff to keep the saws going for them and not put much time in them. I think the ones that leaked under pressure but not vacuum were old Mcculloch or something. They had old boxy Stihl saws too. Now that I think about it I bet the crank bearings were shot because I was always putting seals in those things and they had to run something like 20:1 or 25:1 fuel. I was always fighting the tune on the carbs. I hated working on them.
@@VintageEngineRepairs Could that happen if the bearing was bad and allowed slight movement of the crankshaft? I’m starting to wonder if the new seals were supplementing bad crank bearings. Oops
I have great success with greasing the spring in its seat and it has never fallen out on installation.
Glad that’s worked for yoy
I love Dirko. That is the best stuff I've used.
Yes I haven’t found a better sealant all things considered.
Try threebond 1104 or 1211. Puts dirko to shame.
@@sdc0386 they don’t, I have used both and looked closely at both technical data sheets. The two you mentioned have less fuel resistance, less elasticity, longer cure time and don’t have as high of adherence strength compared to Dirko. Their only advantage is they don’t set in the tube. Dirko requires some Vaseline in the cap to avoid this.
👍
@@Rein_Ciarfella yes. Don’t get me wrong they’re great products and I do use them, but in my experience I haven’t found anything that can top Dirko all things considered.
Nice Tip Tom, no more cut up soda cans for me!
Thanks Ken!
Nice 066. I still run a beast 066 here in British Columbia. I was running my saw a few years ago and it would die when idling. Dropped it off at Walkers saw shop and they found the crank seals leaking,tore it down,new seals,thing runs great again.
Great! I have seen some of Donnys videos, good stuff!
Great tips tom I don't like 2 strokes but will give that a try have one I have to work on I will see how it goes
Nooo! 2 strokes are the best!! 🤩 you’ll grow to love them haha :)
a stihl bg50 has limiter caps, where does stihl have the oem settings at before the caps are installed? or do they have a spec where the L and H screw are installed before adjustments starts before the limiters are pushed on, I do not have a service manual to look this up, thank you
I don’t have that info I’m afraid! Do a quick google search :)
I use Honda Bond on my casings and seals when putting the engine back together. Good Vid
Hondabond is excellent, if I didn’t use Dirko, I’d use Hondabond. Honda also make a good 2 stroke oil too. Hp2
Add grease to the cavity to hold the spring also old trick i learned years ago while mechanicing at thr ford dealer
Yep, a very heavy grease can help 👍
Whats your preferred sealant to use on the seal outer lips? Dirko? Hylomar?
Dirko
TBH, I hadn’t come across these purpose made sleeves before. I’ve always wrapped the sharp edge of the shaft with a couple of winds of stretchy electrical insulation tape and applied a bit of oil to help the lip of the seal slide over it. Never had a problem doing it that way. One thing I would say if making a sleeve on a lathe - the surface must be polished. If cutting tool marks are present, instead of pulling the seal over one sharp edge, it will be pulled over dozens.
Yep you can use electrical tape too :) thanks for sharing!
You can use a Mik bottle plastic type to wrapped around the piston to slide it in the pot.
Yes Pete! What a great suggestion 👍 haven’t tried it myself but I like the idea!
Works well if your in a pinch
You can also use electrical tape to cover the sharp edge of the shaft. It is a little messy to clean up the adhesive from the tape but brake cleaner and paper towel will remove it.
Yes :) I have heard that one before, thanks for sharing!
Just be careful of how much sealant you put on the seal (especially on the clutch side) as in this case you installed the seal into the outer race of the bearing. You don't want excess sealant entering the ball path of the bearing. I would leave the first mm of seal width free of sealant so when installing there is no risk of sealant entering the bearing.
Yep, just enough to seal any damage. 99 percent gets pushed out on install anyway.
I've found that once a chainsaw needs major work, it's cheaper in the long run to just buy a new one. They aren't expensive, and once you have to start fixing them, it becomes endless.
I’m disagree if it’s a good saw. I rebuilt one for 300 dollars. New they’re $2500
Dirko is recommended because it is impervious to virtually everthing. Gas, oil, alcohol, acetone, paint remover, and high temperatures. High end Eurpoean cars use it exclusively as a sealer. Stihl seals may give out in rare instances (usually because the crank has come loose, but the Dirko sealed crankcases, covers, and anything else that needs to be sealed, never leak.
Dirko is a fantastic sealant - the best in my experience, but it’s not fuel resistant. It doesn’t dissolve in fuel, but it does expand and lose elasticity. I contacted elring (the manufacturer of Dirko) who confirmed, it’s not fuel resistant.
@@VintageEngineRepairs, that depends on which one you get. The Curil T2 is fuel resistant. Like I said, Stihl uses Dirko H2 to seal all crankcases and covers and the Dirko doesn't fail.
@@RMartin631 CurilT is not a gap filler and does not set. It’s a totally different product to Dirko and mustn’t be used in place of it.
M.i.g weld gun gas nozzles modified works too
Thanks for sharing 👍
As a machinist it has always bothered me that manufacturers leave sharp edges on seal fits like these. If you think a lip seal is a pain try it with a mechanical seal on a water pump where the rubber bellows may be an inch long. I always cut an angle on these fits if I remake the shaft or chuck up the original shaft and file an angle on it. But for saws like this if someone is working on them all the time and needs an installation tool made there are small machine shops all over that could easily make duplicates of these tools for just a few bucks.
Thanks for watching and sharing!
Do you think a piece of heat-shrink tubing shrunk over the shaft would work?
Someone said it would! I haven’t tried it so can’t confirm though!
Is Dirko better than Permatex No 3? I have three cRyobi chainsaws with seal problems. After watching your videos, I think I can get at least one of them to work.
Yes, they’re not interchangeable and used for different tasks.
Thank you. The Dirko HT is sold in my area as a gasket maker. I've been using Permatex as a gas maker even in my vehicles. I really appreciate the advice and knowledge that I've gained from your videos. BTW, Happy New Year to you and your family.
@@toyotatundra0455 great stuff! Happy new year :)
When I rebuild stihl equipment I use OEM parts, and if a motor is scored I first need to find out what caused it. Changing the seals is cheap insurance. BTW the seal tool is not expensive.
I think it’s about $40 Australian. It’s not expensive as a one off, but when you rebuild as many machines as I do, it’s impossible to buy every seal sleeve for every machine, especially one offs.
Trains is the man!
He’s been very helpful over the years sharing what he has!!!
I use a Chip bag.
Ha cool
Great vids mate, a little help if i may try putting "oil seals" in the title you will get more hits.
Thanks for the feedback!
Does it damage a 2 stroke engine to shut the fuel off and run it til it stops running?
If it’s idling, no :) stihl even recommend you drain the tank and let it idle until it stops when you’re storing them!
i'm on 10% disability actually about 50% but don't claim it and workng on Stihl chainsaws and using them is great also utube channels tell me all I need to know for repairs and safety!
Glad you enjoy my channel :)
Make sure you find the cause of the original failure if you are doing a rebuild. Plugged fuel filter; air leaks on intake boot, fuel lines and gaskets, even a plugged tank vent can ruin the job quickly.
Yep! Agreed :)
Maybe they could add a plastic sleeve with the replacement seal as a kit.
That would be excellent!
Just rebuit a stihl with burned up piston. Didn't know to replace oil seals. Guess we will see what happens
Did you pressure and vacuum test it? If not and you didn’t change seals, it’s highly likely to burn up again in short order.
Pack the sale with grease to keep the seal in place
Yep! A very heavy grease can keep it in!
The price to get that repaired done at a shop could be half the price of a new chain saw
It depends on the cost of a saw. A cheap ryobi, sure, a professional stihl, it won’t (shouldn’t!) be! If I was doing the job I’d give an estimate of 30-60 minutes labor plus parts.
My engine is spooging any tips to help
Yes, either not enough load, too much oil, incorrectly tuned or a blocked air filter.
Tune high speed or low speed screw
@@Donjon-ts6pl well they work together, so probably both. That video at the end of this one (that I point to) will cover how to tune.
Electrical insulation tape works
Thanks for sharing Richard!
Someone could probably design and 3D print a set of those.
Yes!
Sure would be an easy way to make custom seal installing shield guides👌
@@howardosborne8647 yeah!
HUSK-Varna? Where's Claus lol!!
Hahah
There's actually a match simpler solution... Go to the dollar store and buy a set of cheap plastic funnels choose the one that will go over both steps on a large crankshaft and slide the seal back down. 😃
Thanks for sharing :)
Never seen any Husqvarna oil seals having had sealant on them .
Worth adding for insurance
My stihl chainsaw is faulty, it's chain just keeps turning after a little bit of using it and no one can fix it. In service they said it's because the chain is dull, so I had it sharpened but nothing has changed. A big waste of money if you ask me.
Start with basics, turn the idle down. If that doesn’t work, I’d suggest checking that there is no debris in the clutch drum, also if the saw is old it could be new clutch springs are necessary, maybe the needle bearing is damaged or seized. Also an air leak will cause that. Who ever said it needs to be sharpened is talking bs. That won’t change anything and is completely un related.
@@VintageEngineRepairs Thanks for the info, I simply knew it that they were incompetent. Chainsaw is 5-6 years old, not even used that much. I have to turn idle speed down every time I give gas on it, because it just keeps spinning and wasting gasoline and chain oil in idle. I am not a professional repairer so I don't know for sure how to fix it, even those ''professionals'' at the official stihl service in my town don't know how to fix it, but they insist no one makes unofficial repairs since they won't offer their (useless!) services on it anymore.
heat shrink, cheap and easy
I haven’t tried it but glad it works for you
putting the rings on upside down
I have actually seen that happen, but they must have been very worn to fit lol
I don't never have any problems with my husqvarna
Good to hear, though the principles to install seals correctly aren’t brand specific.
Just using electric tape works perfectly
Yes you can do!
It will cut your seal as well, not limited to two cycle engines.
Thanks for sharing 👍
A "gator" seal or a "garter" seal?
It should be garter! Thanks for the correction 👍👍
@@VintageEngineRepairs we used to remove them and cut out 3 or 4 coils and put it back together (it'll screw together like a - well, a screw). This makes it a bit tighter and helps to form the seal lips to the shaft a little tighter.
Cool! Never knew that!
In 60 years of engineering have never put sealent on seals.
4 strokes don’t need it, 2 strokes you should.
destroy ... every time? how many times can you destroy an engine?
However many engines you install seals incorrectly