OOPS! I Destroyed My Customers Blower! Bizarre Diagnosis with an even Crazier Repair!

[@Chickanic]

Thanks for Watching! Find a link to all of my "Must Have", Favorite Tools HERE!! www.amazon.com/shop/chickanic?ref_=cm_sw_r_cp_ud_aipsfshop_aipsfchickanic_9ERPFPBNGQ924P8NS63B

[@wildmanturner]

Rod stretched… piston may have swelled. Together it caused the problem. Cheap Chinese metals and poor heat treat

[@protonhead1]

Putting a extra washer on the plug was the first thing i thought about, but even though it worked ,i worry the customer might think it was a jury rigged repair. But you did the work and found it was the only viable option to keep a cheap blower running. Bravo. And just one more comment. I have been a mechanic on all kinds of equipment for 50 years, and the decline of quality on everything made now is terrible.

[@DanEBoyd]

If the piston keeps on deforming, it will likely occur again.

[@charleshill3789]

Extra washer for the bad design was exactly what i was thinking too..just to make do or return it if you can

[@johndii2194]

jury-rigged? Definitely! But it runs and the price is right. The Guaranty is "It will break again".

[@John-dp3ln]

Question, it worked as shipped then stopped working due to clearance issue? What changed? Thicker head gasket makes sense for a ‘fix’ but issue is a design mistake, rod about 2mm too long?

[@philliphall5198]

What about making a spacer ?? Or try a different plug ?

[@FredColler-g9j]

You and your videos have become my favorite site. At 78 yoa, I am still learning. I have an old old chainsaw that wouldn't run anymore. Following your demonstrations and the tool kit you use, I purchased a carburetor kit and....step by step....slooowly replaced each part with new and reassembled same. Drum roll please. IT RUNS!!!! You were/are my inspiration. Thank you, thank you. And it makes my day when I check the KZbin and you have another presentation.

[@pontiac411]

As thin as the rod is on that unit the rod may be stretching you'll know in a little while if The piston starts hitting the head or the rod breaks.

[@curtisbaker5407]

I have actually done the EXACT SAME THING! AND also have used copper washers in addition to a spark plug squish washer ( to give it the seal needed) to fix things in the past...GREAT FIND Chickanic!

[@beingthere597]

Great mystery story! With one of the failures showing the piston hitting the compression ring, my bet would be an ill-designed or manufactured connecting rod that stretches with use. If the piston crown was weak, I would expect the outer part to go down rather than up, leaving a bulge over the con rod. If this happened though, the center of the crown should not be higher than it was originally. Would be interesting to measure con rod length in a running blower. And I second the comment about using copper washers. Since this may be just a temporary fix, I would warn customers that the same thing could happen again, possibly with catastrophic failure.

[@laserflexr6321]

I'm going with they bumped up the compression with a slightly longer rod and/or thinner head gasket to improve power to weight ratio and fuel efficiency/ emissions and somebody missed it and went too deep when machining the spark plug seat where .005" makes a difference. To do that to a plug, if it was the specified plug, it must have been off by .100 or so. Mashed the plug the first time it was cranked over, but didnt completely close the gap and die until high temp and high RPM, likely the first time it went lean from running out of fuel. HItachi used to have top notch quality control and everything that had that name on it was about as good as you could get in the category, but like everybody else, the consumers will not pay what it costs to make a good one so they too have had to turn over their manufacturing to people who are not as careful and dilligent to get everything just right but do "almost" a lot cheaper. If "almost" is all most people are willing to pay for, we will all get "almost".

[@keithalexander4267]

Connecting rod stretch would be my guess. Bulging results from power stroke deforming piston outer edges downward.

[@richb.4374]

I agree, I think the rods are stretching.

[@drunkingsailor2359]

​@laserflexr6321 Hitachi is now Metabo, supposedly there the same designs and materials. I own a 8 1/4 sliding compound miter saw which they don't make anymore and several of the air guns being Metabo it still calls for oil in line vs Teflon lined cylinder others are going to of course there roofer nail gun is the best nail gun on the market and has been since it's inception.

[@kantemirovskaya1lightninga30]

Was thinking the same thing. At first I thought the piston on the up and down stroke was causing the bulge, but that wouldn’t do it stretching of the rod would

[@CohHfd.4165]

I actually have that exact Hitachi blower that did the exact thing! I did what you showed with the additional spark plug crush washer, and it lit right up!! Thank you for sharing!!!!

[@dennismatthews5592]

Get some copper washers, they work as seals, use them as spacers.

[@alanknoll5540]

Until now I have not heard of a piston in an engine bulging up to smash the spark plug. The manufacturer needs to make a better piston. Awesome video.

[@garymucher4082]

I realize you only covered up the real problem via an extra crush spark plug washer. But since these blowers ran from the start, something has changed with them. Either the piston has metallurgy issues, or the connecting rod stretched. So an extra spark plug washer is only maybe a temporary fix... JMHO

[@dyer2cycle]

I agree, only a temporary fix..but maybe the only cost effective one...new piston/crank, etc. plus labor probably exceed the cost of a new blower..at least this way, you can get some additional use from the blower...for how long, who knows, but otherwise it is junk. I would explain this to the customer first, though...

[@bobbyabbott3035]

It's not going last long!

[@wayneberry8703]

Great fix 👍🏼

[@nelson2231]

Because the rim of the piston looked like it was hitting the head I would not suspect bulging on the piston, I would lean more towards the connecting rod stretching

[@markbernier8434]

I was wondering if the crank is on some sort of polymer instead of a proper bearing and can wear or give over time.

[@MUUKOW3]

No and no rods do not stretch and it has ball bearings and needle bearings.

[@jaydunbar7538]

@@MUUKOW3rods absolutely do stretch, and sometimes stretch more then expected do to a variety of reasons .

[@MUUKOW3]

@@jaydunbar7538 Out of the thousands of engines that have rolled through the shop ,gas ,diesel 2 cycle 4cycle small large . At the track I have never seen such a thing.

[@fireballxl-5748]

When you first gave the description and said "metal to metal".... I cringed at the IDENTICAL TIME you did in the video. Gave me a good laugh because I related to your reaction perfectly in time. As to your solution, I would have thought about that before tearing it down. Some of us not in the business are pretty savvy and I'm sure there were others as well. But I am very happy you actually proved the concept without doubt. Thank you! EDIT: After reading comments below I agree with those who suggested the rod had stretched over time/use. That has to do with quality of materials....metals/alloys. But your "fix" is the most practical and cheap and I would actually try adding a second "booster" washer on the plug for "wiggle room". If the plug holds and combustion is still good.....you have a winner every time! Thanks again!

[@richb.4374]

While one engine is apart, I would get a new replacement rod to compare the length between the affected engine and a new part to verify if the rods are stretching or not. As an alternative, see if someone has a new one or one that hasn't hit the plug yet, and measure the piston depth in the cylinders at TDC to see if they are different.

[@phillmccracken4219]

It looked a bit twisted to me.

[@philliphall5198]

The dome piston has two be the problem, why, is the fuel burning in side the block?? I’m thinking defective piston If you buy a new piston then most likely it is the same batch I need a piston but I’m going to wait for a year because they gave it to me 😮

[@Buzzberski]

For the price point of these blowers, it's the best fix. It will be interesting to see how long this extends the life of the machine. Great solution to extend the life of a budget machine.

[@CFRoach]

To save you time: Since you're going to need a lot of those washers: Pull the washer up to the threads and with a little force it will unscrew. Great video!

[@dyer2cycle]

Yes! exactly, that's what I do...and I would save a few washers for that off old spark plugs...no need robbing one off a new plug, especially as expensive as they are getting these days..NGK and Bosch are not cheap...Chinese ones are not dirt cheap anymore, for that matter...BTW, I have seen some of the Bosch ones stamped Made In China..insane...

[@einfelder8262]

@@dyer2cycle You've seen a Chinese plug with stolen Bosch stamp, not a Bosch made in China.....we hope :);

[@dyer2cycle]

Nope, sadly...original equipment found in Stihl trimmers...@@einfelder8262

[@virgilcollins4925]

Queen of knowledge that's something I never seen before Who would thought about that

[@billm6294]

This is one of your best vids ever and props on good problem solving techniques! Chinese quality control is all over the place, and I can easily believe they have some suspect metallurgy in the piston and/or rod leading to mechanical deformation. One thing to consider is that as rpm climbs (typically above 3500 rpm on a car engine not sure about these smaller types) the tensile load on the rod from piston inertia (reversing the piston weight at the top of the stroke) is actually greater than the compression load from gas combustion. So rods tend to stretch rather than compress.

[@Knightyme]

She said she could feel a slight bulge, I'm more inclined to think the pistons top is being pushed in, causing the bulge that eventually contacts the plug.

[@alisaproctor7725]

After my comment, I saw your explanation and must concur. To prove this is the case, it would be good to compare a new rod to an old one.

[@williamstuessy1611]

Spot on answer....Metallurgy, the Science of, is something the Chinese are still working on. Difficult to translate correctly !

[@boots7859]

@@williamstuessy1611 No, its that the plant manager has a side deal with the steel provider subbing even cheaper pot metal for a kickback.

[@NickManCuso59]

Smart lady. ❤ Love your laugh too !

[@DoingItCheap]

I LOVE it when you have these off the wall problems and share with us. I am in the middle of a rebuild on a kohler twin and play your videos in my shop while working.

[@bertgrau3934]

Just curious, are you going to put over size pistons in as well? I am planning on doing a rebuild on a Kohler V twin as well. For about $500 I can get a complete rebuild kit with over size pistons, and rings. The cost to bore the cylinders isn't cheap, but then a new engine isn't either.

[@DoingItCheap]

@@bertgrau3934 I was lucky. Everything was in specs. Just a thrown rod.

[@bertgrau3934]

@@DoingItCheap Good. The one given to me is locked up, my guess is the rods, but maybe new pistons. A new rod wouldn't be bad. Glad you didn't have a lot of other problems. Good luck with the rest of the build.

[@rodwilliams8932]

Put a cj8 plug in it. Many tanaka / hitachi machines run cj8 plugs due to this issue. hitachi took over tanaka years ago and any hitachi machine you see is made from the entire tanaka specs. hope that helps.

[@AlaskaTony]

you are an amazing story teller and teacher. I love this repair and taking us on the journey you experienced was so much fun!

[@mikeygee2465]

Your expression and excitement is priceless! Thanks for sharing. Always enjoy watching.

[@William_Charles_Baker]

So the questions remain...what caused this and will it happen again?

[@smokinrider]

The wrong plug. Correct plug is a bm6a. Not a bpmr6a. One has an electrode that protrudes. The other doesn’t and is the correct plug.

[@Rotorhead1651]

​@@smokinrider Still doesn't explain the original problem, unless the owner swapped plugs before bringing it to her. Possible, but I doubt it.

[@William_Charles_Baker]

@@smokinrider Wrong plug on ALL 3 of these blowers? And ALL 3 owners said they stopped while running? What are the odds?

[@chrish3720]

The rod has stretched. Take it out and measure it with a good caliper. You will find that the rod has stretched over time.

[@markheatherly2915]

Piston bulge caused contact with plug I bet if someone could check one that is running fine with digital calipers to measure the clearance from the bottom of plug to the top travel of piston the riddle could be confirmed that it dont take much for it to go kaboom if it gets little overheated worked a little harder or ran on store bought premixed like she taught us few videos back they play with the mix to make them run real good seem like more power so you want more of it but in reality they fall apart at higher temp its design engineering meets minimal metal requirements to maximize profits a staple of Chinese ingenuity I even heard a friend in the know once told me the highest quality Chinese parts are sold only inside china and lower quality sold overseas but that's another story. This lady got small engine repairs in the top shelf she is killing it.

[@falcorthewonderdog2758]

Im impressed. You're pretty good.

[@phillipdaulton9861]

Anyone remember “non-fouler’ plug adapters? A hollow spacer that went between the spark plug and the engine. Had some on my ‘63 Beetle. Think I got ‘em from JC Whitney.

[@clinkerclint]

I ran them in cylinders three and four on my 68 chevy truck. They got me several more years of service from the motor before it was retired.

[@artpatronforever]

Non-foulers and retread tires are standard equipment and even required particularly on old cars equipped with manual transmissions that have a Plan B backup engine starting feature for when there is a dead battery. Then you put the car in neutral and push by the opened driver door until it reaches about walking speed and quickly jump in and throw it into low or second gear, while turning the ignition switch to On and immediately popping the clutch to turn over the engine and start it. If you could pick a slope or a hill on which to park before shutting down the engine it was always a work saver to just let gravity get the car rolling downhill so all the grunting and groaning to push the car up to speed is avoided. Back in those days when chromed steel bumpers were on cars, a vehicle with a dead battery could be "bumper jumped" by jamming the nose of one car against the other so the bumpers kissed firmly together, and then a jump could be done using two tire irons like scissors to span the positive poles of the two batteries and complete the circuit. Jumper cables were a luxury not always around, and everybody knew about the "bumper jump" alternative when cars had chrome steel bumpers and glass headlights. Thanks for the memories of simpler times.

[@michaelscholtis440]

You are incredible! Such an elegantly simple solution.

[@clinkerclint]

Sounds like a feature to me :) Automatic compression adjuster piston! Negates ring wear by automatically increasing compression ratio over time! 😆

[@blahorgaslisk7763]

"It's not a bug, it's an undocumented feature..."

[@henryspoota7722]

Odds are the connecting rods are too soft, and have a tendency to stretch. Or just to thin. It appears by what we see from the one piston, is that it initially starts making contact with the head, and then eventually the spark plug. The doming coming from the lengthened connecting rod pushing up the center . Get replacement spec connecting rods, find out tolerances, and compare.. see what you get.

[@58dorsett]

Well, stacking another washer on the plug worked on the orange blower, but what about the green one? The evidence that the piston is hitting the top of the combustion chamber would be a bigger problem. Can't imagine what would cause a piston to bulge up like that. It would be interesting compare a new piston to the damaged one to find out wtf.

[@fredrikanderson6402]

We had that problem on some Hitachi trimmers here in Sweden, and we simply change the plug, instead of a Ngk BPMR7A we used a BM6A which has a shorter tip..! Works great. Actually I never seen a green Hitachi 2-stroke machine before, here they were orange and only the batterymachines were green.

[@albertm8576]

Holy moly!!! Way to go Bre, I love the way you figure out stuff. Keep doing what you do, great fix!!!

[@pythononemo]

You're AMAZING my lady. Great find. I love watching your videos. So glad Ron's hip replacement went well.

[@a.c.king-dk5yl1ep2m]

That was simply BRILLIANT! I always love simple fixes for complicated problems.

[@mrpotatoheadracing]

Rod maybe stretching depending on the material it's made of?

[@danielyeager7287]

I think it would be good to follow the use of this blower because is it possible for the piston deformation to continue? If so, after some more use it may happen again.

[@philliphall5198]

I have one at shop with same problem, I going to wait till she figures it out, was going to buy a brand new and remove piston to compare it, but customer gave the bad one to me so I’m waiting for a while

[@rickharper1497]

Cheap manufacturing. Excellent fix for the problem.

[@kraftzion]

Got mine for $50, left over display model at Lowes. One of my favorite tools. Bad fuel lines are a common problem, had to replace mine within the first month. My anxiety went through the roof watching this video, didn't think you were going to tear one apart.

[@boots7859]

Same here, though the fuel line lasted 2-3 years. Went with the name brand fuel line this time.

[@thomas5890]

I love when outside of the box repairs work so well. I gives you such a good feeling when you fix the seemingly unfixable like that. 🥳

[@bonzai2380]

If the piston is bulging or the connecting rod is stretching this blower is on borrowed time. It would be interesting to see the ultimate failure mode if one after spark plug washer shimming. Keep us posted. Keep up the the interesting videos! Love watching! One additional thought the piston may be cast with a steel ring in bed in the ring land area to control heat expansion if the piston can not expand outward it will expand inward budging the piston dome?

[@ArkansasPilgrim]

All right! That's a Red Neck Repair, if I've ever seen one! Goofy repair, and works like a charm!

[@claytoncoolidge992]

Im going to vote for rod streach. Especially with the scratches something ran down between the piston and cylinder wall when hot and stretched it from the tension

[@RogerJackson-m1i]

I cant get my head around the rod stretching, can it get hot, expand and not shrink? The domed piston crown could be a clue to the cause.

[@timphillips9594]

YOU ARE A GENIUS, GREAT VIDEO

[@richnorman5017]

Need to figure out what’s going on but in the meantime how about using a shorter reach plug in the same heat range??

[@80SWoods]

I’m not certain what Champion plug was used that hit the piston, but when I look up the plug for the Hitachi rb24eap blower, the factory Champion CJ6 they use has a shorter electrode that sticks out about 1/8” less than the one showing in the video. It’s hard to say, but that’s just my guess as I couldn’t see the plug in the video very closely.

[@pyromedichd1]

Interesting problem. I wonder if the extra washer will be a permanent repair. If the piston us actually failing and bulging upward it may continue to do so until it hits again or complete failure. It may also be that the connecting rod is too soft and has stretched under high RPM use. If that's the case it will likely continue to stretch until the problem reemerges. When looking into the top of the cylinder it appeared to have shiny spots around the circumference where the piston was hitting which may be a clue that the connecting rod is stretching allowing the entire piston to reach the top of the cylinder. Hopefully you will report back on the long term outcome.

[@janbastein7355]

Great Video!!! As a kid I removed these spark plug washers to “ stack” them on plugs with longer threads, nothing else was available!!

[@buellrod]

Absolutely fantastic job didn't think it was going to give it enough space. Especially when the pistons already hitting a cylinder. I was thinking about rigging up like a head gasket to get some space in there

[@billywird]

Well, there is no head gasket on this engine but there is a gasket where the cylinder bolts to the crankcase. You know it could be overrevving and causing this problem. You know in past videos she has shown that you can overrev these two cycle engines.

[@brittweir8844]

One of your craziest videos thank you for sharing❤

[@RonHolmes-j1q]

I love your candor and honesty. count the treads on the old plug and on the new plug. I was a machinist, and .015/.020 or +/- can hide very easily. Remember we live in a world with engineers with little practical experience. I spent A LOT of time fixing designs that only work on paper.

[@laserflexr6321]

@@davegeorgia8489 I have spent way too much time arguing with and teaching degreed engineers the basics. Astonishing that some of them had a peice of paper saying they were engineers and worth more to the company than I was. In fact if I look back at the past 25 years, direct dealing with engineers who's designs I had to make in to real parts, I would say less than 10% of them would ever actually be a decent engineer. Only 1 in that time that really knew what they were doing and could turn out a design that worked well without 10 try and miss attempts. And he wasnt there long cause they could get someone else 15% cheaper. It is really disheartening to know within seconds of looking at CAD that it aint gonna work but you have to spend hours making it anyway cause some believe that peice of paper knows more than a person who has been making stuff for 30 years. You tell them right up front what is wrong, and what would work, but few of them will listen cause their hands arent dirty.

[@diavalus]

⁠@@davegeorgia8489as an engineer, I can tell you: if an engineer needs a technician to show/teach them, then those are not good engineers!

[@diavalus]

@@davegeorgia8489 what I was referring to is exactly what you mentioned in your last message. An engineer needs to take all these things in account (unless it is something uncommon). I sometimes see this, with people which are engineers just by name and for example look over the design and say “it should work”, although when I check the design I quickly realize it won’t due to various reasons. I hate it when it happens as a correction needs to be done, which is often time and budged consuming, not to forget someone needs to spend the time doing the correction.

[@RonHolmes-j1q]

I MASSIVELY AGREE@@diavalus

[@Jamwcjconn]

Great video Chickcanic

[@stevenhill1954]

Awesome troubleshooting video, nothing like an experienced mechanic to solve a problem. By the way I write large aircraft maintenance procedures for one of the big aircraft manufacturers. Great job.

[@TheBandit7613]

Any time you have put a few gaskets together?

[@markh.6687]

Him: "If complaint of something rattling in cockpit, remove something." :)

[@charleseddy9903]

You are Amazing, way to go.

[@ytlas3]

Nice. I bought my first Hitachi in 2011 and it's been good. I bought a carb rebuild kit in 2020 and made it like new. It was in 2020 I read they were no longer going to be available so I purchased another one. So far that's been trouble free, but if the pull cord ever locks, I'll know what to look for.

[@MatthewHopkins-u6e]

Looks like a copper washer under the plug is a way to go ... still is the piston crown going to bow still more... great repair Bre

[@TOWNCARBUBBA87]

I’m pretty sure this video probably saved a lot of people time,money and frustration. good job 👍

[@barrylee.freedman2203]

You got a genuine chuckle which left the whole internet with a smile.

[@michaellewis767]

Is it possible that the base gasket as well might have compressed more than its supposed to so you've got two things going on the Piston bulging and the base gasket flattening out

[@Jareick79]

Hmm, so my outboard uses a surface fire design.. Would that work in this application as well? There would be more clearance since there isn't a gap to gap. IDK, I'm merely a novice at engine repairs, just tossing out ideas. 😊. Love the channel. Keep up the good work.

[@sticksnstonestn4120]

When you removed that washer from the spark plug, the spark plug would go deeper into the cylinder and closer to the piston, right?

[@jimmyowen3977]

She put 2 washers on the plug

[@spyder000069]

She took the original washer off and added it as a 2nd washer on a new plug. That moves the plug tip further away from the piston.

[@richschuster1097]

I’m thinking she added a washer from the old plug, so the new plug has two, creating slightly more space. I too wonder how long before the piston distorts more and there’s another failure. But this was great information and a clever fix!

[@1768ify]

Watch again at 10:36, but listen closely.

[@Chickanic]

Yes I added an old washer to new plug for more clearance.

[@michaelhirz208]

Brilliant solution!!!

[@spyder000069]

Would be interesting to double/triple up the head gasket and see if that was enough. At least then the customer wouldn't have to do the double washer in the future which may have other issues with spark plug threads over time. The extra head gaskets may change port timing a bit but they were probably off anyway. Also would be worth putting a set of calipers on the original plug and comparing the tip length to the replacement and see if there was a difference.

[@smokinrider]

There is no head gasket. Barrel and head is all in one.

[@TheKrayusKorianis]

​@@smokinriderThe head gasket being the cylinder gasket to the crankcase.

[@timtimtimmay4654]

@@TheKrayusKorianis At first I thought the same thing, but then realized it may lower compression too far. Then I realized that given the bulging, the compression would be bumped back up. All considered, this seems like a circular problem where the compression goes higher from bulging, creates more heat, causes more bulging, etc. A thicker gasket would likely prolong the life of the blower.

[@jimstraightshooter163]

I have that Hitachi for 4yrs. Starts right up runs great. Now i know how fix it if needed. Thank you

[@KubotaManDan]

Great diagnostic work, where would folks find these compression washers for use on their own engines? Are they sold separately or does another spark plug have to give it up? I use the battery operated blower & weedwhacker theses days, but for decades I used the 2-cycle models. But when quality began to diminish in the small engine products I made the switch.

[@hgbugalou]

I would look at a copper washer to do this. They are sold individually in a variety of sizes for metal to metal seals.

[@kennethpruitt8534]

Racers use what is called "spark plug indexing washers"

[@RICHat22]

@@kennethpruitt8534 I forgot all about that technique. Thanks. Been 30 years since I've done that on a personal engine. If I recall, they come in different thicknesses and look like a crush washer but don't compress.

[@bay9876]

A dead blower brought back to life over a very simple fix. Good job and the patient is doing well.

[@kennethpruitt8534]

Not sure if anyone noticed but at about 9:30 in the video when you were looking at the underside of the piston and connecting rod it appeared (could just be the camera), that both the piston and connecting rod had been subjected to extreme heat almost to the point of seeing temper bands. That could explain the piston's change shape resulting in damaged plugs. I'm curious what would happen if you tried a "surface gap" plug? I'm just an amateur mechanical sleuth who is not sure the problem isn't still there even if the symptoms have been relieved. Your thoughts.....................

[@barryallison9307]

I would give you two thumbs up for just taking the first blower apart just to see what went wrong. However, I think you deserve three thumbs up for trying the washer/spacer trick to see if it fixed the problem! Way to go!!

[@terryalextexas8638]

Armchair mechanic here. Heck, I’ve worked on at least 3 blowers so I do consider myself a bit of an expert. It’s quite obvious and I’m surprised nobody else caught it. The whatchamacallit was way too far to the left. So far that it was interfering with the doohickey. This caused the thingamajig to overheat and pushed the piston into reverse. This can all be fixed with a couple of solid blows from a left handed 8 lb sledge hammer 😜 Luv your channel.

[@johngrossbohlin7582]

Perhaps they started using a thinner base gasket than what was originally specified, or a base gasket with too much crush.... Perhaps using a layer of Permatex gasket on both sides of the existing gasket would gain enough clearance.

[@rpddoc]

I’ve had this same Hitachi blower for about 4 years and use it at home year round and commercially during the summer. No problems except for having to replace the fuel lines. Keeping fingers crossed this doesn’t happen to mine. Great vid!

[@dab1068]

My brain is screaming at you right now because, if the piston is bulging, what is to keep it from continuing to bulge and ultimately fail in a few uses? You may have come up with a work around temporarily but is it permanent? I guess we shall see.

[@Chickanic]

Most of these $179 blowers are 6-8 years old. It took that long for it to get in this state. I figure if it can limp through a little longer, they got their moneys worth out of it. It also might last forever. Who knows?

[@JimmyBallew]

I have the same Hitachi blower, when i decided to change the spark plug i got what was supposed to be the right one at Lowes and had the same issue with the replacement, i put the oem plug back in and the problem went away. It's still running on the oem plug.

[@northfloridatech1820]

Rod stretched...

[@Digidoc316]

The cylinder perimeter, away from the central spark plug, shows impact with the piston rim. This indicates a wrist pin, rod bearing, or crankshaft bearing failure. While washering the plug for clearance may allow it to run, the piston is STILL hitting the head mushrooming the piston rim. I would consider putting a 0.004" copper wire gasket between the case and the cylinder. Compression may suffer slightly but it should provide enough clearance for both the plug and the head.

[@William_Charles_Baker]

Very easy to measure the squish and then determine exactly how thick a copper base gasket will be needed to fix the issue.

[@chatrkat]

Before you disassembled the Hitachi, I was expecting, we’d find a composite connecting rod! 😂 And, looking at the Tanaka, that thing had almost no hours on it, the plastic opening around the muffler was free of carbon residue. Taking a wild guess, I wonder if those pistons are made of such light gauge material that they are in fact, expanding and bulging upward a several thousands?. Overall the little engine looks to be decent design for being a lower cost machine. Regardless, makes me happy I own slightly older Stihl and Echo pro equipment. Great video Bri I enjoyed watching with my coffee this morning. ❤️ from Chicago.

[@joebalazsy7559]

Is it possible that the piston rod might have slightly stretched thus causing the piston to move higher in the cylinder? This would result in hitting the spark plug, the top of the cylinder, and if hitting it hard enough, deform the piston head in this way. Check the piston rod for stretch.

[@billwessels207]

An easier way to remove the washer from a spark plug is to unscrew it by tipping up one side of the washer and starting it on the threads and unscrew it. Might have to griip the outside of the washer at first to turn it.

[@stevea6722]

It was probably fun putting the Hitachi blower back together. If the piston top is bulging upwards might want to take a look at the bottom side of it. There may be some cracking along the pin struts allowing the piston top to separate. A new, revised piston might be in order.

[@gappmast9712]

I would double check with the manufacturer on the spark plug recommendation. If the piston dome was weak it would go down not up. Also check closer on the crank journal and pin clearance there could be a bad roller that doesn't feel loose until it's in the right position.

[@daninuesca3801]

Holy crap i did the same thing with MY Tanaka version..Didn't look inside of it yet...You're the BEST!..👍🤙🏽

[@KPrimeau1]

Is she the best? If she isn't I haven't met them yet. Thank you and your hunky husband for backing you up on this channel.

[@williamwelch7]

Thanks Bre

[@rickcourtney9247]

Had a lawnmower i let a friend use while i was deployed. Being a nice guy he did an oil an plug change and before i got back... wrong plug punched an electrode sized hole in the piston head. Being on an E4 pay i couldn't afford a new mower so took a shot and filled the hole with JB Weld... worked for the 4 years i had the mower before upgrading. Not recommended but necessity sometimes inspires unconventional fixes😊

[@kenibnanak5554]

Suspicion.., the wrist pin holding the pistol to the piston arm is too soft (plastic?) and bent with repeated cycling. This allows the piston to get too close to the spark plug on the up stroke. On the down stroke the inside of the piston, because of the bending of the wrist pin, the inside rear of the piston is now being bulged up by repeated contact with the piston rod. If I am correct, one alternate fix for this situation, other than the spark plug washer, would be to replace the wrist pin with one less likely to bend or deform.

[@gerardjohnson2106]

Job well done. 👏👏

[@lawnmowerjones3160]

Hi, I had that very same problem a while ago. The customer brought his hitachi blower in and wouldn’t start, but did pull over with no issues. I quickly grabbed an NGK BPMR6A and stuck that in, then pulled, my hart sank!!! That’s it I owe the customer a new blower. I picked up the plug that came out, it was an NGKBPM6A Which has a very slightly shorter nose. I cleaned the old plug and put it back in. I was lucky like you no hole in the piston and got it running. Thanks LMJ

[@billwessels207]

You and your husband have a great mix of tech and great camera work along with upbeat personality.

[@johnobiro5202]

I thought before you said it, ‘try another washer on the plug’. The piston must be really getting hot to make the top go soft enough to warp. Probably cheap steel. Great blog Bre. 🔧👍🇬🇧

[@stevekurtenbach1951]

I had one of these blowers and tore it apart many times and could never getting it to run and I could not find anything wrong. I was so frustrated and ended up throwing the thing away. I still think about it when I'm alone. It broke my heart not knowing why it would not run. Now I think I know. Now those memories can die. Thank you.

[@pdevonport7266]

I would say its Piston warp caused by excessive heat, just like a cheap aluminium frying pan forms a dome. The blower probably works for most people but given the right conditions like a hot day and a hard workout then after the engine cools down a dome is is left because of the cheap thin, aluminium piston.

[@bigwhiskey83]

What it like a .050 fifty thousandths thick washer dam! Than you for tearing apart shows people can tear apart and find problem ! Great find thank you!

[@awac4577]

Wow! Great job.

[@d.faulkner8210]

happened to me before ,guilty of buying Chinese crap, great video

[@raymondrobinson5251]

I thought of a thicker head gasket! But hey! Gasket on sparkplug! Genius! No teardown of unit! Thumbs up 👍!

[@richardschwarz1039]

you can fix anything But love the way you can`t leave a problem go unsolved

[@JavierPerez-gs3gm]

Yes! that piston top was buldged! Improper two stroke mix on this Hitachi/Tanaka/Metabo's can overheat the piston head and make it softer and this will happen!!! They are great engines, specially on trimmers! Strong!

[@Harry-fk6yh]

First let me state I have no idea what plug you installed in the blower but it sounds like a plug with to long a reach. That said...I have one of the green blowers and it came with a CJ6 spark plug. No issues with the plug hitting the top of the piston. I bought mine in 2017 or 18. I checked the owners manual (which is readily available online for free.) It states... Spark Plug CJ6 FOR USA. CAN. It also lists a BMR7A. I have never tried a BMR7A in mine, always used the Champion CJ6. No hitting the piston, no extra washers. I have a BPM7A spark plug laying around and the electrode protrudes way to much compared to the CJ6 causing the piston to hit the plug ( too long of a reach.) Hope this saves you money, time and frustration. By the way I love your channel. Keep up the good work.

[@rellmonger7935]

I got the orange version of this 2014. I changed the carburetor only 2021. I bought my brother 1 & he took it to a shop. Yep they put in wrong plug. I replaced his carburetor too. They work great. Matter fact mine been sitting outside on my back porch. I use it to blow my leaves off. Our carburetor was leaking gas on the inside of the engine & was hydro lock the engine. Well on his. I fixed his 10 minutes & gave him the spark plug out of mine.😊

[@glennmckinley3058]

My guess is whatever caused the score marks on the piston got on top and blocked the last tiny bit of piston travel but not enough to cause catastrophic damage, just the bulge. I’d look at the intake track and carburetor for missing hardware.

[@skyepilotte11]

Excellent...curiosity to figure out a metallurgical issue with Chinese junk ..keep up the good work.

[@TravisDoesFirewood]

VERY smart idea with the washer especially if you have extras from damaged plugs. Congrats!