Where's WYK been, and what trouble is he making?

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So this happened.

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View of the top of the piston:

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It's a Dolmar 420c. I was present when it occurred. It was in a long cut, started to lose power, then died. After the usual stuff of checking fuel etc. I slowly pulled it over and noticed it had much less compression than it should have. Removed the front plate off the exhaust and saw that little divot in the top corner of the piston there. I took it home and tore into it expecting to see carnage. But - there wasn't any. Just that little divot in the piston and big signs of detonation or impacts on the piston itself. At first I thought it may have been due to piston bits in the engine, but there wasn't any sign of impact on the combustion chamber. The jug was in great condition. No signs of damage, even at the lips on the exhaust port it looked good. Sides of the piston looked great. In fact, when I removed the front of the muffler and looked at it, all I saw was the piston face at first, and I thought - that looks good. Then I slowly turned her over and saw the missing chunk on the crown and thought 'That's not so good'. Spark plug was perfect with great color.
There is plenty of carbon build up, though. And, this thing had no real work done on the muffler. These saws are high in compression with tiny squish bands straight fro the factory.

So here's what I think happened:
After 5 years of happy firewood duty, a chunk of carbon maybe got stuck in the combustion chamber on top of the crown, breaking off a piece of the crown but not making a mark on the carbon build up already in the chamber. The piece(s) finds it's way out quickly enough not to do any real damage, but due to that very sharp divot, loads of detonation began to happen. Eventually between the divot and the piston damage, she doesn't have enough compression to run once the engine is fully warmed up or running hot. Either that, or carbon build up on the crown itself caused high compression and detonation, leading to the crown damage. Whatcha think?
I didn't see any signs of extended detonation(usually discolouration) under the piston crown, though.

I put a spare piston from another Dolmar 420 that died long ago, a new caber ring, ported the cylinder properly, removed the spark screen and added another outlet, added more holes in the top cover to allow better breathing(but not crazy or anything like I did on the 241). She is pretty strong now, and sounds fantastic.
 
Dynamic piston modification, assisted by organic material. It could be a casting flaw, though I'd have expected it to rear its ugly head long before now. Tight squish & carbon build up aint exactly a good mix for long life.
 
So you've seen my photos of trees. But did you know they were in a show?



In the show, Vikings, Season 6 EP18(and some of ep 19), they film these areas:

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^ The rather unique looking Douglas Fir on the right appears in the clip at :45 from the opposite angle.

This is the steps shown from the opposite side they filmed from at te start of the clip:

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Trees in the clip:

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And it FINALLY explains why this boat was in a river that really couldn't be navigated for all the stones and rocks in it(also explains all the burned floor where the fires were):

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Happy new years!
 
Thanks for the post. Yeah, the hospitals are starting to fill up due to covid and flu etc. So the guvmint is a bit panicked. Also, they want to fill up all the old folks with vaccines before it's too late. We got 4.9mil in the Republic, and 1mil vaccines through Feb. So wish us luck there. None of my family members so far have been infected. Our neighbors caught covid at Christmas, and they are still wrecked from it off and on months later. So ya really don't want it.
A friend of mine is a health care worker and has had his shots. He had flu-like symptoms for 48 hours afterwards. So the shot is no picnic, either.
We run our hospitals like Toyota runs it's factory. Just enough to keep the place moving, and just in time. While it may be efficient and more affordable to run it this way, when you get a pandemic, it messes everything up :(
Our current lockdown is you can't travel more than 5km from your home for exercise. Ya gotta at least try to work from home if ya can. No sit down eating. No groups, no sports unless professional, etc etc.
So we all feel a bit couped up.

We prolly made the news because our covid spiked pretty badly over the holidays. We've such a small population that any small change can mean a lot in stats. Still, the mad thing is our stats are way better than almost every other state outside the EU.
Sweden has double our population, but 4X the death rate from covid. We're like 1/3500 or so, Sweden is 1/850 ish, and the USA is 1/750. So I wouldn't worry about us. :(
Sweden practiced super light regulation at first(basically told everyone to be careful for a start), sort of like the US. So now we know how those things worked. I am curious to see all the data once it becomes available.

In the midst of the epidemic I started this site: https://sugiharabarsuk.co.uk/ - hasn't made any money, tho.
Sorta hard to get stock at the moment, too. And it's not like we're floating in cash right now either :(

I always have my eye on things stateside. Man, what a ride it's been, 2020. Between the politics and the pandemic, dunno how ya pulled thru. Still see a lot of nonsense and stupidity about the place. But, hey, that the US for ya.
CDC just put out a terrible number. 22,000 died due to flu complications the year before. Nearly 400,000 died from Covid complications.

So how is everyone else gotten on? What's yer pandemic experiences?
 
Thanks for the post. Yeah, the hospitals are starting to fill up due to covid and flu etc. So the guvmint is a bit panicked. Also, they want to fill up all the old folks with vaccines before it's too late. We got 4.9mil in the Republic, and 1mil vaccines through Feb. So wish us luck there. None of my family members so far have been infected. Our neighbors caught covid at Christmas, and they are still wrecked from it off and on months later. So ya really don't want it.
A friend of mine is a health care worker and has had his shots. He had flu-like symptoms for 48 hours afterwards. So the shot is no picnic, either.
We run our hospitals like Toyota runs it's factory. Just enough to keep the place moving, and just in time. While it may be efficient and more affordable to run it this way, when you get a pandemic, it messes everything up :(
Our current lockdown is you can't travel more than 5km from your home for exercise. Ya gotta at least try to work from home if ya can. No sit down eating. No groups, no sports unless professional, etc etc.
So we all feel a bit couped up.

We prolly made the news because our covid spiked pretty badly over the holidays. We've such a small population that any small change can mean a lot in stats. Still, the mad thing is our stats are way better than almost every other state outside the EU.
Sweden has double our population, but 4X the death rate from covid. We're like 1/3500 or so, Sweden is 1/850 ish, and the USA is 1/750. So I wouldn't worry about us. :(
Sweden practiced super light regulation at first(basically told everyone to be careful for a start), sort of like the US. So now we know how those things worked. I am curious to see all the data once it becomes available.

In the midst of the epidemic I started this site: https://sugiharabarsuk.co.uk/ - hasn't made any money, tho.
Sorta hard to get stock at the moment, too. And it's not like we're floating in cash right now either :(

I always have my eye on things stateside. Man, what a ride it's been, 2020. Between the politics and the pandemic, dunno how ya pulled thru. Still see a lot of nonsense and stupidity about the place. But, hey, that the US for ya.
CDC just put out a terrible number. 22,000 died due to flu complications the year before. Nearly 400,000 died from Covid complications.

So how is everyone else gotten on? What's yer pandemic experiences?
WA state has kept us more or less locked down since Feb 2020, so far our numbers are better then most of the country, though it isn't looking real good, a lot of people full on hate the Governor for the lock downs etc.

CA and especially LA are getting slammed hard currently, ICU's are full, Morgues too Haven't heard from other states, but it taint looking good at all. Folks continue to prance around sans masks and have big family gatherings, parties etc, then a month later grandma is dead and no one seems to give a ****.
 
This pandemic really shows how much we care about our elderly :(
If it killed children, some people would build bunkers and hide in them. But old folks? **** em seems to be the attitude.
I even heard so much on a radio show once. The host said something along the lines of they've lived their lives, so why can't we?
 
This pandemic really shows how much we care about our elderly :(
If it killed children, some people would build bunkers and hide in them. But old folks? **** em seems to be the attitude.
I even heard so much on a radio show once. The host said something along the lines of they've lived their lives, so why can't we?
Screw the first responders too, we got to get the teachers vaccinated before old folks, cops, & firemen. If your in an expensive home, you get vaccinated, otherwise you have to survive another month or three before your shot. The amount of stupid in this country is, well, downheartening and, as we experience, deadly. My job has me immersed with the non-mask crowd, even when the masks are provided free. We are not, as it seems, in this all together. As a frontline worker, the words "hero" are a lie, "expendable" is more in line with the truth.
 
Myanmar military coup condemned by the US - "Who do they think they are? America?"
thats some Irony... though we do have a new regime here...

Last I heard Myanmar has most of its issues from a Coup from several years ago, So maybe the Military there is stepping in to set things right finally? Though I don't know enough about it to say one way or the other.
 
Couple buddies of mine work with retirement homes, my ma used to work in one in WY, hasn't been any good news in that field for a very long time.

Suffice to say... pray yer dead before your kids force you to "live" in one.

The Pandemic is merely bringing the truth to the surface

Forgot to mention, cause it's sort of tragic and depressing, but the bud of mine that works in healthcare told me the other day he was so depressed he didn't care if he died tomorrow or all the death he had seen, and all the sleep he's lost. :(
Bless the poor man.
 

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