OUCH! what happened and why? 2 stroke Piston Failures

[@RotacRepair]

A brilliant presentation! Nothing like this anywhere on the internet. Thank you.

[@EricksonMachinePerformance]

It's taken a while to save all these damaged pistons to make a video. Thanks for watching and commenting

[@michaelpotts8625]

I need some help how do I contact you sir

[@thirdgearboogie2210]

Thank you! I've seen multiple videos on spark plug reading. I have never seen anybody do an in-depth tutorial on reading Pistons. Thank you for sharing your wealth of knowledge🤘

[@EricksonMachinePerformance]

Thanks for watching

[@batteryman16]

Hey Mark, I'm missing your videos. I hope all is well with you and your family. I'm looking forward to seeing your video on piston wash.

[@bennyblanko3]

Keep making video bud! Much appreciated. So much information in so little time. You not only are an expert, but can convey that information precisely and quickly. I'm doing my first top end this week on a 2001 yamaha 800xl this weekend. I hope I figure out why it feels like it is running out of fuel after full throttle and warmed up. I went through the tank, carbs. But, pulling the motor was the last resort. I hope it is just gunked up sticking power valves. They look great on the outside, rotate perfectly, and I cleaned them about 5 years ago when I put waveeater clips on them. But, the inside might be different. Beyond that, do you have any ideas? It has clean carbs, runs crisp (stock, and at 5500 feet elevation is where we live, near a lake) any other ideas. Still has the stock yamaha fuel lines. But, I took everything apart fuel line wise and fuel tank and pickup, and didn't see anything clogged. It started at the end of last season, after overfilling the fuel tank, and hitting a big wake, I think?

[@EricksonMachinePerformance]

If you want email me the pictures of the damage [e-mail]

[@stco2426]

Brilliant and many thanks. Great presentation!

[@oldschooldirtbikes9960]

Awesome…..!!!! Very informative on piston failure. I had a new piston on my 88 cr500 that had a head gasket failure that washed away the premix that you describe to the T…!!! Keep up the great work.

[@EricksonMachinePerformance]

Thank you 🤘🤘

[@marinzeraja5416]

I was hoping you would mention pre-ignition as well for detonation but all around great video

[@EricksonMachinePerformance]

@marinzeraja5416 Great comment. Yeah, it's tricky to fit every failure method in 1 video without missing something. My plan is to do a Dyno video and show what's going on when these events occur. I will try to show pre-ignition in that video. This video was mainly to take the guesswork out of WHY a 2 stroke engine failed. Thanks for commenting

[@christianthejetskiguy]

One of your best informative videos mark , keep up the great work!

[@EricksonMachinePerformance]

Thank you

[@mathieu94]

Hello sir, could you tell me something about fixed bearing position and free bearing positions? I work with big windturbines and in these gearboxes and generators, the bearings always have a free bearing position and a fixed bearing position to allow axial movement because of expansion due to heat. But on smaller engines like 50cc two strokes i can hardly find any information about this. Do you happen to know anything about this? Kind regards!

[@legenderekfixes]

Hate when my cylinder tchrinks! 😂 Very informative! Thumbs up bud👍

[@EricksonMachinePerformance]

Thanks for watching

[@gabrielalvarez9570]

Very Knowledgeable, And straightforward Info, Thank You! 🙏

[@EricksonMachinePerformance]

Thanks for watching

[@msoto951]

This was a great video. I have a 2000 rm125 bored to a 134. After 3 seasons the piston melted on the exhaust side. Should it bump up the main jet?

[@EricksonMachinePerformance]

I'd check the carb. Maybe it clogged the main. If it lasted 3 seasons I would ASSUME it was correct and something else happened

[@redsmagic4907]

It is often said that a design error in the engine itself can result in severe knocking or side slap of the piston, leading to damage. Sometimes changing the plugs solves the problem, which is a very difficult part.

[@EricksonMachinePerformance]

Knock and piston rock are 2 very different things. Piston slap is from either to much clearance, or being worn out, or not being warmed up correctly will not get better by changing plugs. Pre ign , knock can sometimes be helped changing plugs, but even then Normally needs higher octane fuel, or timing , fueling, or boost adjustments to safely solve the issue

[@redsmagic4907]

@@EricksonMachinePerformance The solution I took earlier was to change the plugs. The standard is NGK CMR7H, but when I replaced it with CMR6A, which has a shorter reach, things surprisingly improved. I don't know if the manufacturer didn't test it enough or if it was a design error.

[@EricksonMachinePerformance]

@redsmagic4907 may I ask what engine? Year, make, and model?

[@redsmagic4907]

@@EricksonMachinePerformance I was talking about a 45cc engine for radio controlled models. The problem I described was so bad that it took a long time to resolve.

[@pgbpro20]

I bought a blown up 2015 YZ. Massive detonation damage. The timing (aligned marks) was WAY off. Set it with a dial indicator to factory specs and have been all set since. Its easy to jump to the carburetor or the seals. But rod bearings, crank bearings, timing, and the head (did someone cut yours along the way?) all need to be checked.

[@EricksonMachinePerformance]

@pgbpro20 You're right. Many people blame the wrong thing for their failure. That's why we made this video to help. These pistons were collected from different engines we have rebuilt for customers over the years. When we rebuild an engine, we go thru everything, and if it's a topend we do for a customer, we point them in the direction where to look and what caused the last failure to try to avoid it happening again. Thanks for watching and commenting.

[@jeffbryner5355]

So where your merch when robbing a bank if thats my shenanigans? Kidding Kidding 😂😂

[@EricksonMachinePerformance]

Lol

[@jeffbryner5355]

@EricksonMachinePerformance I'm glad you liked that. I was like um hope I don't make him mad lol

[@EricksonMachinePerformance]

@jeffbryner5355 buddy I got thick skin and I can take a joke. Thanks for commenting, buddy. I appreciate you

[@jeffbryner5355]

@EricksonMachinePerformance good to know! I work in a sign fabrication it's nothing but shit talking all day! You are welcome mark keep up the good content my friend

[@outlawwill5483]

My skirt shattered on the intake side. (2nd time) I am boring it 1mm over to solve the loose piston problem. I need to clean all the aluminum out of the bottom end. Will I need to replace the bearings even if there is no movement in the rod. It's a 2 stroke. And I seen black oil on thee counter weight when I turned it over which seems odd

[@EricksonMachinePerformance]

If you broke the skirt odds are the crank bearings need to be replaced. I'd recommend having it inspected

[@flow-fpv7781]

god dam you are a brilliant wealth of knowledge, their is no substitute for experience keep up the great content!

[@EricksonMachinePerformance]

Thank you. 😊

[@ralfrimrott493]

06 YZ250 lean I melted the top at the exhaust port same damage as presented in video

[@abhimanyuinjeti5326]

Great content!

[@EricksonMachinePerformance]

@@abhimanyuinjeti5326 ty

[@carllinden533]

Sachsenring Trabant 601 engines must be extremely undstressed, they seem to run no matter how bad the bearings, carburetors or even rotary valves are.

[@peanutbutterisfu]

Pre ignition is an uncontrolled air/fuel mixture firing before tdc and detonation is after. Pre ignition breaks pistons, bends rods, ruins rod bearings.

[@artisgrietens5535]

So i melted piston rings and piston in my outboard i think i have bad fuel pump can cause that? On low throttle it go good and then full throttle and i hear ticking noise and engine stoped fast 💀

[@Op1zilla]

Dang, This was Great info for any 2 Stroke Person, Thanks 👽👍🏻 🚴🏼💥☁☁☁☁

[@EricksonMachinePerformance]

Thanks for watching

[@RwP223]

Piston Wash, Let's Gooo!! Hel yeah thanks man

[@fishydubsfishing6516]

One good thing is they make good ashtrays

[@kadurahmanpuzhakara7032]

Is piston will caught due to carburettor damage?

[@EricksonMachinePerformance]

You could melt a piston if the carb is clogged or isn't tuned correctly

[@konstantinkover1050]

nice.....great info

[@jnljnl8485]

Had an 85 rm250 that the cylinder would not hold round long enough to wear out the piston.😂 The cylinder liners were junk in those early 80's Suzuki's. I had it bored every month. It never took less than .030 over to get it round again. Went trough two cylinders and sold it.

[@EricksonMachinePerformance]

That sucks!!

[@CowboyAxe]

How often will 87 octane detonate inside a chainsaw? honestly I hardly remember anybody having that problem. Big chainsaws too.

[@EricksonMachinePerformance]

I'll be honest the only chain saws I have messed with the engines on are hotsaws . The bigger issue is normally new fuels don't sit well. So if you're leaving the saw, sit longer than a week or 2, you should use fuel stabilizer. As to newer saws needing higher octane, I'm not sure

[@CowboyAxe]

@@EricksonMachinePerformanceThank you.

[@mjrybread]

I see one here that most pistons dont in your video

[@harleylif1929]

If you fuel got water in it could you see the same water damage and speed

[@mjrybread]

Do 2 stroke pistons have to have those two tiny holes ,,

[@Newmyyy]

Depends on application and piston manufacturing. Cast pistons should NOT need drilling. Forged can utilize it on certain power valves motors like a CR250 (02-07 models specifically). The forged pistons can expand at a different rate than cast hence the holes.

[@mjrybread]

@@Newmyyy from much research I've learned it is to lubrication the exhaust bridge,,

[@EricksonMachinePerformance]

It can be done for both cast and forged. It's to cool the bridge port. It's mainly done on race engines or performance engines that have alot of wide open throttle

[@EricksonMachinePerformance]

The holes in that area to help cool and lube the bridge port.

[@reidaaustin]

Was waiting to see if there was a sbt failure haha…

[@EricksonMachinePerformance]

😉

[@ramdart74]

Funny you say that, I just had one. 20 hours on the engine. Looks like a ring broke. Under warranty but I’m thinking I’ll just fix it myself, really don’t want to deal with them. The heads were installed backwards from the start. Tigershark 1000

[@EricksonMachinePerformance]

@ramdart74 your better off repairing with Quality parts and machine work. If you want email us id be happy to help. [e-mail]

[@eitssholdon5248]

Forged Piston was best for 2stroke ..

[@NickHol]

10/10

[@EricksonMachinePerformance]

Thank you!

[@skorner5798]

" The lower rod bearing starts to go and the piston comes up higher " ! Physics would say Impossible due to a thing called COMPRESSION - sorry mate dead wrong on that one , otherwise very knowledgeable , well done .

[@EricksonMachinePerformance]

@@skorner5798 it's inertia. 100% happens. It's fairly common. Thanks for watching and commenting. I understand why you would think that way. The inertia of the piston is what causes it to continue to travel upwords. Have a great day

[@jamesaucutt8284]

Seems like you’re just using two-stroke pistons for all of this considering they only have two rings and the length of the piston skirt. I would imagine it would happen more on a two-stroke engine, considering they run a high rpm, and they run very hot.

[@EricksonMachinePerformance]

This video is only about 2 stroke piston failures like it says in the title. 2 stroke and 4 stroke pistons fail in different ways. This video is meant to help someone diagnose their failure

[@torpedotomfpv3669]

Duuuude thanks so much for your longterm learned knowledge packed in this 16min clip. I learned so much 🙏🏻🫵🏻

[@EricksonMachinePerformance]

Happy it helped. Thanks for watching