My dad has an older Troy Bilt tiller with electric start. It just sits
and spins when you start it. It has a section on the flywheel with
broken teeth. Can I repair the flywheel cheaply or is the only option
to by a new one. I like the electric start feature and it saves my arm
from serious yanking in the cord. If I take the starter off and start
it with the rope then turn it off and put the starter back on the
electric start will work for one or two tries than I guess it gets to
the part of the flywheel without teeth and just spins again.
Could I use a MIG welder and just build up those spaces carefully? I
am guessing probably not.
"Mike Behnke" wrote: Find the local dealer of the engine
brand and buy a new flywheel.
^^^^^^^^^^^
Obviously, that will work. In the meantime, I will mention that I once
repaired some broken teeth on a cast-iron gear of a printing press (Multi)
by brazing, and then shaping the buildup with a file.
Since you are able to gain some advantage by rope starting, it suggests
another solution. The engine is coming to rest in a couple of spots when
you shut it down, and these are the places where the teeth are gone. If you
loosen the spark plug , rotate the engine about 1/4 turn with the rope, and
then retighten the plug, the starter may engage well enough to get the
engine spinning.
Er, no.
First off, the engine could easily be rotated 1/4 turn with the spark plug
in place by means of the pull-rope. There is no need to loosen and
retighten the plug. Secondly, doing as you suggest will only worsen the
damage to the flywheel and will very likely chew up the starter drive
pinion as well.
The correct solution is the one that was already mentioned -- purchase a
new flywheel/ring gear assembly. They are not expensive or difficult to
replace.
The teeth are more than likely broken at the compression area, I have seen
many flywheels from outboards that have worn teeth in the same place. What
engine is it? I have many just sitting in the shed.
Why not give it a shot.... can't break it cuz it's already broke. I
would only caution not to get that area too hot. Weld a little bit,
then let it cool down. Hit it again later, let it cool, etc., etc.
After you have the teeth built up enough, use a small grinder to
reshape. There ain't a whole lot of stress on those teeth as it's
only a one-banger (and probably not a *lot* of compression.)
I'd go for it.
Ken.
Christ, I hope whoever uses this technique to fix his $30 flywheel
willingly works for $0.00/hr and gets his materials for free. Otherwise,
it'll be far cheaper and easier to just go get a new flywheel for the
engine.
I dunno about MIG, but I've done a weld repair on the starter teeth of
an automobile flywheel. As others have advised, if your flywheel is a
cheap and easily obtained part, go with replacement. But you can weld
a couple of beads where the tooth was, then grind it down to an
approximation of the tooth profile. I used stellite for its wear
resistant qualities.
- GWE
|
|Christ, I hope whoever uses this technique to fix his $30 flywheel
|willingly works for $0.00/hr and gets his materials for free. Otherwise,
|it'll be far cheaper and easier to just go get a new flywheel for the
|engine.
What fun would that be??
Some people just like to fix things for the sake of seeing if they can do it.
And you only notice the aggravation on the weekend, when the store is closed but
your welder etc are handy.
Just had a thought: If this is like some automotive flywheels, with a toothed
ring pressed onto the flywheel, you could conceivable knock the ring off, move
it 90 degrees, and re-install (heat it first). This would give you good teeth at
the compression area.
Rex in Fort Worth
I have an old 7 HP Troy Bilt Horse and it never requires more than 2
pulls to start. (even after sitting all winter long). It has
automatic compression release so hand starting is easy.
I'd just remove all that electric start crap and get it tuned up.
That depends on the brand of engine. If it's a Briggs then the ring
gear is probably easily replaced at least on the newer engines.
Actually it has to be since they've gone to selling them with plastic
ring gears which don't hold up. If this is the case then be sure and
get the aluminum replacement. It'll last a whole lot longer.
If it's got a Kohler engine then it's a different story. I'm not
sure on the newer models but the older models the ring gear isn't
replacable and the flywheel is very expensive.
Wayne Cook
Shamrock, TX
"Daniel J. Stern" wrote: First off, the engine could easily be rotated 1/4
turn with the spark plug in place by means of the pull-rope. There is no
need to loosen and retighten the plug. Secondly, doing as you suggest will
only worsen the damage to the flywheel and will very likely chew up the
starter drive pinion as well.(clip)
^^^^^^^^^^^^^
Daniel, I hope I am not as dumb as I seem to you. This was my thinking:
When you pull the rope, the compression generally causes it to stop in the
same two spots, which is why there are usually two areas on the ring gear
that go bad. If you stop pulling as the piston goes up on compression, it
will rotate in reverse and stop. If you go past top-dead-center, it will
rotate forward to another spot and stop. Those are the two particular spots
you want to avoid to get around this problem.
When you put power to the starter motor, the pinion engages the flywheel
before the engine starts to turn. Therefore, it seems to me the pinion
would be fully engaged before the damaged teeth came around, so I would not
expect the pinion to be damaged. The damage which usually occurs to the
pinion in this situation comes from continuing to try to start when the
ring-gear teeth have gone bad. Typically, you hear the gears grinding, and
the motor does not turn.
Obvioiusly, the practical, sensible solution is to buy a new ring gear, as
you say. But, as others have noted, many of us enjoy the challenge and
sense of accomplishment in "outwitting" the system. You may not choose that
for yourself, but I often do. (My family thinks I'm nuts. But they call on
me when things need fixing, and that makes me feel useful.)
I don't know where you buy your parts from, but I sell replacement
parts for Briggs and Kohler and neither on sells "$30 flywheels". A
Briggs heavy flywheel (for use with a tiller) with ring gear will run
about $100- $180 and a Kohler will go for around $300. Even a
weedeater flywheel goes for over $50.
-Carl
That may be true, but it is reality.
You can buy a whole lawnmower for less than the cost of a replacement
engine, and often for less than the cost of either the short block or
the "magneto"
Tillers and snowblowers are getting pretty close. A brand new "scratch
and dent" from home depot or Lowes or whoever can cost about the same
as a replacement engine for an Ariens or other high end blower or
tiller, and it is the IDENTICAL engine. Usually a Tecumseh Sno King on
the blowers.
Up here a utility engine is generally pretty close to $100 per
horsepower, brand new, ready to run.
Surplus you can do better, IF you can find your configuration. I
bought a 5 HP Sno King with less than 20 hours on it for $50 almost 10
years ago. Went looking for one to replace a snowblower engine that
broke a camshaft this winter - nothing worth looking at for less than
$200 (about 10 years old, and well used).
Left the old Ariens sit - I'll likely end up putting a cam in it this
spring. In the meantime, if we get a heavy snow I get to blow out the
neighbour's driveway.
I had a small engine shop a few years back, and I can agree that many
flywheels are very expensive! A "plain" flywheel for a 8 HP B&S can run near
$100, add a ring gear and add $50 to that price. Pretty crazy when a new
engine can be had for $400 or so.
Greg
Don -
My dad had a Horse and it worked and worked. He finally shipped it back
to them and got it retrofitted. What happened - he was willing to get his
baby fixed - they offered him a new - but model under one. He was very
pleased as the 15 years it worked in the sandy loam it was warn.
The new one showed up and was just as good, but easier for him to control.
I can't say they will do the same thing again but they do fix.
Martin
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