December 1982 - American Bonanza Society
December 1982 - American Bonanza Society
December 1982 - American Bonanza Society
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Colvin's Corner<br />
J . Norman Colvin<br />
Retired Beech Project Engineer<br />
on <strong>Bonanza</strong>s and Barons<br />
ABS Technical Consultant<br />
Service Ctinic tnspector<br />
35'S SLOW FLAP OPERATION<br />
Dear Norm:<br />
The flap motor on my Straight 35,<br />
S I N 0· 13 13 , has developed a " flat"<br />
spot (or so I'm told), and it is in need of<br />
replacement/ repair.<br />
Considering the extremely long<br />
extension and retraction time of this<br />
model, is it possible to install a flap<br />
motor which will decrease these<br />
extension and retraction times It so,<br />
what is involved What is the cost<br />
T. M. Sullivan<br />
ASS # 11 590<br />
ELECTRICAL PROBLEMS -<br />
V-35B<br />
Oear Norm:<br />
I have a 1977 V-35S, S I N 10063,<br />
with a few cranky electrical problems.<br />
1) In the August issue there was a<br />
discussion of a repair to a G-33<br />
subpanel lighting system. Is my system<br />
the same I have replaced the<br />
transistor and potentiometer.<br />
Occasionally I when rheostat is run all<br />
lhe way up, the panel will lighl up<br />
briefly lhen go out. If th e sysl em is the<br />
same 400 cycle, should I replace the<br />
inverter next<br />
2) The tesl circuit of the three green<br />
position lights fails to light ri ght main<br />
gear light, yet when the gear is put<br />
down all is green. Should I suspect th e<br />
right gear-down position switch Does it<br />
have dual pOints, one for down position<br />
and one for up (test position)<br />
3) Left fuel gauge often fails to<br />
indicate. In analyzing the circuit I<br />
understand th e two sending units<br />
" leak" a smaller or greater amount of<br />
current to ground (they are in series),<br />
thereby giving the graduated mading.<br />
(When inboard sender is disconnected<br />
gauge deflection is severe·to-full.) I<br />
have checked contacts on back of the<br />
gauge and at fu se buss. Should I<br />
suspect a bad gauge<br />
4) Right fuel gauge upon reaching<br />
1/ 2 to 5 / 8 begins to flick to full<br />
sharply until gauge reading gets below<br />
1/ 2, then it settles down. I suspect<br />
poor winding contact on one of the two<br />
sending units. The inboard unit was<br />
replaced under warranty for the same<br />
problem and was okay for about a year.<br />
Should I zero in on the inboard gauge<br />
again<br />
These little electrical problems are<br />
very annoying, and I would like your<br />
comments before I start replacing parts<br />
on a trial / error basis.<br />
5) Grease level in gearbox - I seem<br />
to remember many issues ago a<br />
discussion of grease leakage due to<br />
overfilling. At our last annual my IA said<br />
the box required grease. Since then<br />
grease is leaking through the belly<br />
drain holes. Yet, a careful inspection of<br />
the bottom seal shows no seepage at<br />
all. Is there a seal at both the motor<br />
mounting and the hand crank shaft I<br />
have lowered my main struts due to<br />
removing the step. Could that cause the<br />
box grease to leak out of the crank<br />
seal or a vent hole if it is overfilled<br />
Enjoy your column very much -<br />
keep up the good work.<br />
Roy N. Foxworthy<br />
ASS # 41 34<br />
Dear Mr. Foxworthy:<br />
The most logical source of trouble in<br />
the panel lighting system is the inverter.<br />
It should be replaced. The inverter most<br />
likely is producing too much power,<br />
thus blowing a transistor in the system.<br />
The landing gear test circuit most<br />
likely has a blown diode since th e<br />
trouble seems confined to the test<br />
circuit. Yes, the circuit has dual points.<br />
The most logical source of trouble in<br />
your fuel gauging circuit is th e printed<br />
circuit board. These PC boards are<br />
located above the fuel gauges and<br />
att ach to the instrument panel flange. If<br />
only one tank is giving trouble, switch<br />
PC board s to see if the trouble moves.<br />
PC boards have been improved, so new<br />
boards should be more reliable.<br />
When landing gear gearboxes are<br />
overfilled with grease the surplus<br />
grease works oul the emergency gear<br />
handle seal. Due to overfilling there<br />
also may be some leakage out the vent<br />
hole on the top side of the gearbox.<br />
Fluid level in the gearbox should only<br />
be high enough for the worm gear to<br />
pick up lubricant. This can be observed<br />
through the filler hole. Only correct<br />
lubricant (Mobile #626) should be<br />
used in th e gearbox. The gearbox<br />
spline shaft which runs through th e<br />
gearbox is sealed at top and bottom by<br />
Garlock seals. Any leak at these pOints<br />
would be unusual and obvious. If the<br />
seals are leaking, seal replacement<br />
would be necessary. It appears that<br />
your trouble is a simple case of<br />
overfilling, and I would Question with<br />
what kind of grease. Strut inflation has<br />
nothing to do with the leakage.<br />
Dear Mr. Sullivan:<br />
The flap motor in your <strong>Bonanza</strong> is<br />
considerably different than in<br />
later-model <strong>Bonanza</strong>s, so there is<br />
nothing that can be done to speed up<br />
flap movement. It wouldn't hurt to<br />
check the electrical circuit for high<br />
resistance; but on your model <strong>Bonanza</strong>,<br />
flap speed is just slow.<br />
SOUND INSULATION FOR<br />
ENGINE COWLING<br />
Dear Norm:<br />
I have two items for discussion!<br />
In the May , <strong>1982</strong> issue you wrote to<br />
apply " Vaporite 550" for insulation.<br />
The product is manufactured by the<br />
Anderson Pritchard Oil Company. I<br />
called Beechcraft West; and, after<br />
calling the factory, th ey advise me it is<br />
not available. Would you please give<br />
me an address for Pritchard I have<br />
another supplier who may be able to<br />
obtain it for me. What else would you<br />
recommend be applied to the underside<br />
of th e cowling for noise reduction<br />
I have been reading aboul the<br />
importance of keeping the gyro<br />
pressure pump inline filter clean. Mine<br />
turns black in 25 hours use (V·35A). I<br />
get the feeling the pump is wearing<br />
rapidly. Is this normal<br />
The ASS Newsletters are fantasti c! I<br />
praise and tell every <strong>Bonanza</strong> owner I<br />
meet to join.<br />
Stanley C. Meyer<br />
ASS "'3001<br />
Dear Mr. Meyer:<br />
Vaporite 500 would not be good<br />
malerial for the underside of the engine<br />
cowl. Engine heat might cause it to<br />
melt.<br />
I feel it would be a waste of time to<br />
insulate the cowl since that does not<br />
cause noise in th e cabin. If the cowl<br />
doors were to be insulated, I would use<br />
Scotch Foam Y·370, which is a 3M<br />
product.<br />
The bulk of noise in the cabin comes<br />
through the windshield and side<br />
windows. Some noise comes through<br />
the side fuselage skin between the<br />
firewall and door post.<br />
page 1268<br />
american bonanza society