| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 784.1 | Dogbones? | MAGIC1::BEAUDET | Beware...the Junk_Yard_Dog! | Wed Nov 30 1988 10:32 | 15 |
|
Maybe your problem is the dogbones! If they are stock, they're
not suppose to last very long - especially running in grass...
You may wish to try reverse without load on your wheels to see
if the noise is torque/stress related.
I'm not real familiar with the Blackfoot transmission, but my
buddy's son has had to replace transmission gears several times
because he also runs in the grass - he has also replaced the stock
dogbones with "aftermarket" ones.
|
| 784.2 | You may be right! | KAOA11::BORDA | No one expects the Spanish Inquisition | Wed Nov 30 1988 11:18 | 8 |
| re:.1
Yes the noise is definately torque/stress related,if you run the
gear box with no load,the noise is not there,but if you put a load
on the tires it starts to pop.
I wonder if the ends of the dogbones or the cups are worn and they
are slipping under load.
Les Borda.
|
| 784.3 | Wild WIlly | LEDS::COHEN | | Wed Nov 30 1988 12:44 | 14 |
|
My Wild Willy has the same sort of gearbox as the Blackfoot. I
had a similar problem. I'm not sure about the Blackfoot, but
Willy has an intermediate gear between the pinion and spur gear
that was nylon. Under heavy load, the pinion could slip the
intermediate gear, making a loud "clicking" type noise as the car
moved. on inspection, the gear look quite normal, and it took a
while to figure out what was wrong. Ultimately, I discovered that
the nylon gear was soft enough for the metal gear to deform the teeth
and turn past it, after which the teeth would return to nearly
their same shape. adjusting the mesh so that it was tighter
eliminated the noise, but also increased the rolling resistance a
lot. I found a compatable gear in the Handbook of Small Drive
Components, made of glass filled nylon, that fixed the problem.
|
| 784.4 | re.3 | KAOA11::BORDA | No one expects the Spanish Inquisition | Wed Nov 30 1988 13:24 | 3 |
| Thanx Randy,how are things.
The strange part about this is it never did this before until a
few days ago and it progressively is getting worse.
|
| 784.5 | | OHUNDO::SENECHAL | MS-DOS? | Wed Nov 30 1988 13:59 | 11 |
|
The front diff on my Hotshot made some ugly popping noises once,
when I took it apart I found that a dowel was no longer holding
its idler gear in place and letting it bounce off the housing.
Maybe one of your gears has some extra play that lets it move around
and bounce off of something (the case, another gear?). It could
be that going forward it's being pushed into the proper position
so there is no popping then.
-- Don
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| 784.6 | Sounds like the bevel gears tro me. | CTHULU::YERAZUNIS | I can add, test, and branch; therefore I am. | Fri Dec 02 1988 11:10 | 7 |
| I had that problem on my old Frog; it turned out the sides of the
diff case had flexed out enough to let the spider gears (bevel gears)
pop occasionally.
Bending or reshimming the case should take care of the problem.
-Bill
|
| 784.7 | re.3 and Repair steps so far. | KAOA11::BORDA | No one expects the Spanish Inquisition | Fri Dec 02 1988 11:43 | 11 |
| re.6
Thanx for the info.So far i have changed the half shaft set(dogbones
& cups)because they looked worn on the ends,this did not work.Last
night(LATE LAST NIGHT)I replaced the bevel gears they had several
gouges on them and quite a bit of fillings in the grease and I only
ran this gear box maybe 15 minutes since tearing it apart and cleaning
it all up.I have not had a chance to test drive it yet but I'll
keep your suggestion in mind.Wonder why the box would go out of
tolerance because I have never taken it apart prior to this problem?
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| 784.8 | What kind of box is it? | CTHULU::YERAZUNIS | I can add, test, and branch; therefore I am. | Fri Dec 02 1988 12:57 | 19 |
| Is the diff box an aluminum-sided box (like a Frog) or an all-plastic
box (like a HotShot)?
The Frog-style box can get flexed out by whacking too many rocks
or just bad luck in assembly. The Hotshot box, being only plastic,
is subject to heat warping (ever leave the black plastic in the
sun?)
Either way, see if you can feel much play- ten thousandths is about
the tolerable limit. If it's more than that, you'll have to cobble
up some shims out of (paper, brass, aluminum, cardboard, etc) to
take up the play. Otherwise, those new bevels will just get ripped
up like the old ones did.
(you _can_ ball-pein an aluminum-sided box like a frog box back
into tolerance. I did. It's mentally nerve-wracking, but if you
feel lucky, try it.)
-Bill
|
| 784.9 | re.7 | KAOO01::BORDA | No one expects the Spanish Inquisition | Fri Dec 02 1988 13:25 | 9 |
| Yes Bill it is an aluminum sided box.The play you are talking about
must be on the inside of those keyed plastic bearing supports??There
is a little movement in and out (not a lot)maybe I should correct
this.I suppose a small round shim could be cut to fit between the
bearing support and the aluminum to allow the support to come in
closer contact with the bevel gears.
Thanx
Les Borda.
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| 784.10 | you're in luck! | CTHULU::YERAZUNIS | Why are so few of us left healthy, active, and without personali | Fri Dec 02 1988 17:24 | 9 |
| Try the ball-peining first (i.e. bending the sides of the case inward).
Do this with no gears inside!
Then fit the gear assembly. The aluminum will bend easily if you
got it too tight, so this isn't a critical step. Try flexing the
case in 1/16" and see how it does.
-Bill
|