How do I know to replace a carburetor on a small engine instead of
rebuilding the carburetor?

On 9/26/2010 7:13 PM, Jon Claude Killy wrote:
How do I know to replace a carburetor on a small engine instead of
rebuilding the carburetor?

Rebuilding works 98% of the time.

What to look for to determine if replacement is needed.
1. missing parts.
2. broken parts.

Running swill like Arco gas through it will certainly cause any
soft parts to degrade and need replacement a lot sooner.

Jeff

On Sun, 26 Sep 2010 17:13:19 -0700 (PDT), Jon Claude Killy
wrote:

How do I know to replace a carburetor on a small engine instead of
rebuilding the carburetor?

Sorry, but my crystal ball is in the shop and therefore I can't devine
what you have and what problem you're trying to solve.

I have five chain saws and fix about a dozen more for the local wood
chucks. Also weed whackers and blowers. Most of the fuel related
problems I see are not caused by a tar and varnish clogged carburetor.
It's the [deleted expletive] filter on the end of the fuel line at the
bottom of the tank that gets clogged. There are also plenty of carbon
encrusted reed valves (old saws) and intake and exhaust outlets that
get clogged. I give the carb a blast of carb cleaner to remove any
varnish and gum, and then fix the other likely candidates, such as a
clogged air filter, crud on the spark plug, magneto problems, dirty
points, etc.

However, I have one Husqvarna 136 where the problem really was in the
carburetor. The previous owner torqued down the needle valves causing
the soft aluminum valve seat to deform. I could make it run, but it
wouldn't stay adjusted as the difference between lean and flooded was
about 1/8th of a turn. $50 for a new Walbro carb was a bit much, but
a rebuild kit would not have helped. By the time I was done, I had
put more into this old saw than it was worth.

If you must learn by destroying(tm), a rebuild kit costs about $15 and
an hour of your time. Try rebuilding first. If that doesn't work,
look again at the obvious other problems. Last, buy a new carb. If
that doesn't work, buy a new saw.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 26 Sep 2010 19:38:19 -0500, Jeffrey Angus
wrote:

On 9/26/2010 7:13 PM, Jon Claude Killy wrote:
How do I know to replace a carburetor on a small engine instead of
rebuilding the carburetor?

Rebuilding works 98% of the time.

Yep, on chain saws. However, I'm zero for 5 attempts on automobile
carburetors. After 5 disasters, I gave up.

What to look for to determine if replacement is needed.
1. missing parts.
2. broken parts.

Assuming a chain saw or lawn mower:
3. Brass needle valve with a circular grove and a matching grove in
the seat.
4. Clogged intake to the cylinder.
5. Clogged fuel line.
6. Clogged fuel filter.
7. Clogged air filter.
8. Debris in the carb after the air filter was punctured.
9. Wrong fuel or bad fuel/oil mix.
10. Far too much Sta-Bil in the fuel.
11. Water in everything.
12. Mangled throttle linkage.
13. Automagic choke stuck either open or closed.
14. Timing adjustment on magneto position.

and the winner that took me several days to find.
15. Permanently shorted cutoff switch.

Running swill like Arco gas through it will certainly cause any
soft parts to degrade and need replacement a lot sooner.

You should see what's left of my Homelite EZ when my semi-brilliant
neighbor used Coleman camp fuel (naphtha) and a 50:1 oil mix. Worked
great until the piston froze in the cylinder. I'll fix it one of
these days when I feel like relieving my frustrations by pounding out
the piston with a 2x4 and a sledge hammer.

However, you're right. Some solvents, cleaners, and gas additives
attack rubber parts. The same neighbor mentioned that the saw seemed
to be leaking oil, which I confirmed. What he didn't tell me is that
he put some kind of solvent in with the chain oil to "clean it"
resulting in all the rubber seals turning to slimy goo.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 26 Sep 2010 17:13:19 -0700, Jon Claude Killy wrote:

How do I know to replace a carburetor on a small engine instead of
rebuilding the carburetor?

Why in the hell would you think asking this question in an "electronics
repair" news group would be the right thing to do?

That aside, if you cannot answer the question yourself you should take
the entire motorized mechanism to a qualified small motor mechanic for
advice.



--
Live Fast, Die Young and Leave a Pretty Corpse

On Sep 26, 5:38*pm, Jeffrey Angus wrote:
On 9/26/2010 7:13 PM, Jon Claude Killy wrote:

How do I know to replace a carburetor on a small engine instead
of
rebuilding the carburetor?

Rebuilding works 98% of the time.

What to look for to determine if replacement is needed.
1. missing parts.
2. broken parts.

Running swill like Arco gas through it will certainly cause any
soft parts to degrade and need replacement a lot sooner.

Jeff

So which gas is _not _ swill in your humble opinion? I only ask
because I've been running Arco for 25 years.

G²

On 9/27/2010 6:44 PM, wrote:
Jeffrey Angus wrote:

Running swill like Arco gas through it will certainly cause any
soft parts to degrade and need replacement a lot sooner.

Jeff

So which gas is _not _ swill in your humble opinion? I only ask
because I've been running Arco for 25 years.

The problem is the oxygenation (and other additives). It seriously
kills the soft rubber parts like the pickup tube to the filter
element in chainsaws and other small 2-cycle engines. It's not
quite as problematic in 4-cycle engines other than the rubber lines
and primer bulbs if they have them

The other problem is usage. Unlike automobiles, most power tools
sit idle for weeks at a time.

What I told people to use when working as a service tech at the
Yamada Co. was either Exon, Mobile (now the same) or Chevron.
And to spring for premium. You're engine runs better and stays
cleaner inside.

Also, premix the CORRECT amount of Stabile(tm) in a 1-5 gallon
fuel can. As others poited out, too much is worse than none.

And NEVER let your friends borrow a chainsaw. I saw it over and
over, "But we only had one more cut when we ran out of gas so..."
(We welded the piston into the engine.)

Jeff
The other other one.

On Mon, 27 Sep 2010 16:44:18 -0700 (PDT), wrote:

On Sep 26, 5:38*pm, Jeffrey Angus wrote:
On 9/26/2010 7:13 PM, Jon Claude Killy wrote:

How do I know to replace a carburetor on a small engine instead
of
rebuilding the carburetor?

Rebuilding works 98% of the time.

What to look for to determine if replacement is needed.
1. missing parts.
2. broken parts.

Running swill like Arco gas through it will certainly cause any
soft parts to degrade and need replacement a lot sooner.

Jeff

So which gas is _not _ swill in your humble opinion? I only ask
because I've been running Arco for 25 years.

G²

All gas is the same except for the additives... The additives are
added when the tanker truck (semi) is loaded with fuel to deliver to
the stations, then it bcomes 'branded'.

On Sep 27, 7:04*pm, Jeffrey Angus wrote:
On 9/27/2010 6:44 PM, wrote:

Jeffrey Angus *wrote:
* *Running swill like Arco gas through it will certainly cause any
* *soft parts to degrade and need replacement a lot sooner.

* *Jeff

So which gas is _not _ swill in your humble opinion? I only ask
because I've been running Arco for 25 years.

The problem is the oxygenation (and other additives). It seriously
kills the soft rubber parts like the pickup tube to the filter
element in chainsaws and other small 2-cycle engines. It's not
quite as problematic in 4-cycle engines other than the rubber lines
and primer bulbs if they have them

The other problem is usage. Unlike automobiles, most power tools
sit idle for weeks at a time.

What I told people to use when working as a service tech at the
Yamada Co. was either Exon, Mobile (now the same) or Chevron.
And to spring for premium. You're engine runs better and stays
cleaner inside.

Also, premix the CORRECT amount of Stabile(tm) in a 1-5 gallon
fuel can. As others poited out, too much is worse than none.

And NEVER let your friends borrow a chainsaw. I saw it over and
over, "But we only had one more cut when we ran out of gas so..."
(We welded the piston into the engine.)

Jeff
The other other one.

But that oxygenation stuff is mandatory in all gas in CA - where I've
been running the Arco.

G²