When to replace top end

[Charles Bale]

An empty carb is a happy carb. Especially ones that have a float bowl.

 

[holeycow]

In my experience over many years of many small engines that is simply not correct with good fuel. As stated above, good fuel (premium, non ethanol mixed fuel) can sit in a saw for a very long time and not hurt it. In fact it is beneficial.

2 different schools of thought here.

 

[Charles Bale]

When the gas evaporates, it leaves behind the oil, and will varnish, Plugging up the emulsifying holes in the jets. Does not matter if the fuel is of high quality. (it does matter if its ethanol though, whole other can of worms) Gas just sitting in a carb, or fuel injector is a bad thing. Good thing about carbs, is its ez to drain them. And in the case of these diaphragm carbs, you can run them dry or use the "primer" bulb to draw the fuel out of them.

Empty carbs, and full fuel tanks lead to happy fuel systems.

I am an aircraft mechanic, trust me, its true.

 

[Little Al]

If guys actually saw what these saws go through under professional use they would realize they stand no chance of actually wearing one out for a legitimate reason even at 50:1. It’s usually bad gas that gets a weekend cutter.

Agree 100% A correctly tuned saw can stand all the hard work that can be thrown at it it's lean mix or not enough oil that is a saw killer as a faller of repute & good skills said to me years ago 'God protect us from enthusiastic amateurs withe a limited amount of knowledge"

 

[holeycow]

we all have seen deposits in carbs from evaporated gas. That happens over a long period of time as the gas evaporates (varies with particular equipment). And yes, it is particularly troublesome in float bowls IF you don't leave the gas to flow (meaning for example, shutting the petcock off in a motorcycle). I leave the petcock on. I keep the tanks full. I use good fuel with conditioner. They sit for months. They are ok. Note that the time spent sitting in my world is generally winter and cold, which greatly reduces the evaporative effect to nearly nill.

Trust me, I am a farmer and amateur enthusiast with many years experience.

like I said twice already, there are two schools of thought on this. Each has valid arguments. Just don't use ethanol garbage in small engines! That goes a long way to prevent fuel system issues.

each to his own

 

[Charles Bale]

Well if there's something we can agree on its ethanol is bad bad bad. So bad that it's illegal to put in airplanes. there is a cool website, pure-gas.org or something like that, its got a map of all the gas stations with non ethanol available.

 

[holeycow]

I get your point completely. I think the problem is what each of us deems "long term storage". A few months, even up to a year is not "long term" to me (with proper fuel). After that I start thinking about it.

 

[Mad Professor]

we all have seen deposits in carbs from evaporated gas. That happens over a long period of time as the gas evaporates (varies with particular equipment). And yes, it is particularly troublesome in float bowls IF you don't leave the gas to flow (meaning for example, shutting the petcock off in a motorcycle). I leave the petcock on. I keep the tanks full. I use good fuel with conditioner. They sit for months. They are ok. Note that the time spent sitting in my world is generally winter and cold, which greatly reduces the evaporative effect to nearly nill.

Trust me, I am a farmer and amateur enthusiast with many years experience.

like I said twice already, there are two schools of thought on this. Each has valid arguments. Just don't use ethanol garbage in small engines! That goes a long way to prevent fuel system issues.

each to his own

I owned bikes for many years and wrenched at a MC dealership a few summers when I was in college. The best thing you can do for long storage is shut the petcock and open the fuel bowl drain(s). We used to work on bikes with up to six carbs. It's a lot of work to clean six, then have to sync them all too.

WE just got non-corn fuel around here again recently. I do use that in all small engines and equipment. For saws I still use 100LL. Properly stored with good oil the mix will last years. Drawback is lead and a slightly different tune. I try to keep a log of tune for my saws if I have to switch between 100LL and non-corn premium. If I happen to have to run corn-fuel I don't let it sit more than a month and re-fill with non-corn or run it dry.

 

[holeycow]

ya, but you were working on Honda's. They are special needs machines. joking.

 

[Mad Professor]

ya, but you were working on Honda's. They are special needs machines. joking.

The special needs machines came in a big cardboard box with missing and extra parts . Saw shops get those too.

 

[Charles Bale]

thats what I try to tell everybody in the small town I live in: (lots of people want me to fix there stuff, dont really want to) what's more important than even changing your oil is when you put the machine away for the winter if it has a battery you have to: shut off the fuel petcock drain the carb and unhook the negative battery cable.

Then it has a very good chance starting up in the spring!

We're Lucky in Alaska they don't ship that corn crap up here!

 

[Mad Professor]

thats what I try to tell everybody in the small town I live in: (lots of people want me to fix there stuff, dont really want to) what's more important than even changing your oil is when you put the machine away for the winter if it has a battery you have to: shut off the fuel petcock drain the carb and unhook the negative battery cable.

Then it has a very good chance starting up in the spring!

We're Lucky in Alaska they don't ship that corn crap up here!

Put the bat inside, in the cellar, on a wood plank.

 

[Greaser007]

Here's my story, _ _ _ and i'm stickin-to-it ! hahaha
When to change the top end:
I bought my 2100 CD Husky way-back in 1984 at a yard sale for $200, and it looked like a worn-out Faller's saw with 36-inches of bar sticking out of the saw.
I didn't even try to start it when I got it home. The first thing I did was to tear it down and install new Crankshaft Seals. Upon inspection of the barrel, yes, it Did have a couple of spots where the chrome liner had worn through. Do I replace the barrel ? …. Heavens Forbid ! ….. I am a blue-collar worker, and I don't have a big-piggy bank, so what does the happy home-owner do ? ………. put the engine back together, and with the existing ring, because the end-gap was correct.
That was 1984, and that saw cut 6-chords of firewood for me each year for 15-years. Then I moved to the Pacific Coast in Fortuna, California, and seldom used the saw until I moved back to the Shasta County area in 2003, where large Digger Pine trees proliferate. I often buck trees that my 36-inch bar cannot reach through, and must buck from both sides. This 2100 Husky is still running strong today. I used it this morning to cut up large tree forks which the hydraulic splitter will not touch.

My recommendation is to run that Puppy ! ………… and use 32:1 mix for keeping the engine cool and lubed.

Now about all the hype about fuel going bad _ _ _ _ I just don't have issues with my equipment or vehicles with carbs. Now, the inverse can be said for the guys in the shops because they see the horror stories of equipment-gone-bad. The reason for Equip-gone-bad is this ( Neglect ) !! Most consumers do not give their equipment regular service. If you made your living with a saw such as a timber faller, you faithfully service that saw Daily with "tender-loving-care". I allow fuel to sit in my motorhome with 413 Chrysler engine carbureted, and after 24-years of ownership, I just don't see fuel issues that bother me. sorry guys but I don't let my stuff sit idle for 5-years and then take it to the shop.

If you are towing a trailer, and running your fuel ratio lean, you build heat and burn valves or burn holes in pistons. I know I did it when racing when leaned-out too much.
Now, when towing with my 460 Ford engine, I purposefully run my fuel mixture Rich to keep that engine cool under a hard pull. If you run a 32:1 gas to oil ratio, that is a cool mix which may prevent overheating the engine or worse yet Siezing-Up.

This works for me, but may not work for the next guy.

 

[mbrick]

That's quite a story.
Also, cutting rounds bigger than 36" across sounds pretty exciting, I've only seen up to about 24" so far and that's still a lot of firewood.

Thanks for the input. I'll keep running it because it seems like the cylinder kits are for saws that suffer a catastrophic failure and not slowly wearing out.

 

[Greaser007]

Hey mbrick,,
I am not familiar with the 550 XP, but that sounds like a large cube power head. My guess is it pulls real nice and always a treat to throw chips with vigor.
And realistically, the cost of a barrel and piston sounds reasonable just to know your upper-end is "Fresh" and at it's best.
In my motorcycle racing days (early 1970's) I would service my bike to be at it's best if I could expect to win a race. So, I spend hours servicing my old saws to keep them running their very best. And the payback is rewarding.
Last summer I was sitting on a cut bank of the highway at a road construction site. Another motorist pulled up and the driver came over and we began visiting. Come to find out, the guy was a timber-faller, and I told him I have a 2100 CD and a 394 XP. He said he had just bought a new saw that morning, and took me over to his pickup and opened his saw-box, and there was a brand new power-head. His "old-faithful" saw Siezed on him the previous day, and he said "I was not going to rebuild that saw again." I don't remember what size it was, but that goes to show you that even with daily servicing, there reaches a point in time where we must move forward with newer equipment. ….. and retire the "old-gray-mare." _ _ _ hahaha