Click Here For Installation Instructions
Beech Fuel Gauge Printed Circuit Board Modules
Are Your Fuel Gauges Erratic--Wobbly?
Suddenly Go To Empty--(Or Full)?
These Are The Gadgets That Make Your Fuel Gauges Erratic!
You're flying along, when suddenly a fuel gauge drops to Empty-- making your passengers nervous. You turn on a Nav light or some other switch and sometimes the gauge will come up again--but not always!
Chances are 99 out of 100 the fuel gauge printed circuit boards are faulty, causing erratic and inconsistent fuel gauge reading.
These printed circuit boards are amplifiers that go between the senders in the tanks and the fuel gauges themselves. They amplify the signal coming from the tank senders to something the fuel gauges can read.
The units themselves are about 1-1/4" square and 1/2" thick. They are tan in color and located under a lip at the top of the instrument panel on the back side, just above the manifold pressure gauge. There are two of them--one for each fuel gauge and they are interchangeable.
Easy To Replace
To get at them, remove the glare shield by removing one screw at each side of the glare shield and disconnecting the air hose underneath.
The printed circuit boards are held under the panel lip by 2 screws each. There may be a piece of Velcro over the screw heads, which should be peeled back first.
Each unit has 5 wires coming out of it that normally terminate in a nylon connector plug. Just squeeze the ears on the plug and they will come apart. That's all there is to removing them!
Some planes, mainly Barons, do not have the nylon plugs--the wires are butt-spliced. If this is the case--cut off the connector plug furnished with the rebuilt unit and butt splice again with suitable splice connectors--or--upon request, we will supply mating connectors to fit the plugs we furnish with the unit.
Each unit consists of a printed circuit board on which electronic components are mounted, put in a plastic case and filled with a hard epoxy.
Birks Aviation Products re-builds the units on an exchange basis--taking in old units--taking them apart--(with great difficulty!)--replacing faulty components with newer, more dependable one, and re-assembling them in a new case and refilling with epoxy.
Each unit is tested after rebuilding and before filling with epoxy. After the units are completely reassembled and filled with epoxy, they are given a thorough environmental testing. Each unit is cold tested in a freezer and hot tested in an oven, as well as subjected to torsional twisting tests. Units are serially numbered to aid in later identification should problems arise.
3 Generations Of Gauges
There are 3 generations of fuel gauge printed circuit board modules for Beech airplanes. The oldest or first generation units are about 2" square and bolt directly on the back of each fuel gauge. They are not encased in epoxy and all the components are exposed. They are generally identified as P/N 58-324042. The 2nd generation units are described on the first page and are P/N 58-364041 and 58-364058.
The 3rd, or newest generation, is Beech's current retro-fit kit consisting of 2 open circuit boards about 2 1/2" square mounted on an aluminun panel and covered with a black plastic cover. This assembly costs about $2,900, plus installation. This assembly mounts in the same location as the 2nd generation units, and has flat, red-colored connector plugs. The units are not encased in epoxy and each individual circuit board can be removed for repair. These units are susceptible to voltage spikes and if the plane is jump-started or loses an alternator, it often blows out several components and parts of the foil on the circuit board. These units normally have a Part Number 58-364058-13 (or -11) on a yellow tape on the connector plug.
Birks Aviation Products repairs all 3 generations of these printed circuit boards at the same price. Units normally can be turned around in about one day.
The bulk of the units in use are the 2nd generation epoxy-encased units. Birks Aviation Products has an exchange program for these units and we are normally able to shop out rebuilt units from stock. Old units can then be sent back to us after the rebuilt units are installed. That way the airplane is only down once, with the removal of the old units and installation of the rebuilt units being done simultaneously. There is a core charge for the old units, which is credited when the old units are returned to Birks Aviation Products.
These units are guaranteed for 6 months and will be replaced at no charge if they fail within that period.
There is an exchange program for the 1st, 2nd and 3rd generation units. We normally only have a few of the 1st and 3rd generation units in stock so we ask that the old units be returned as quickly as possible.
All units repaired or rebuilt by Birks Aviation Products are calibrated for a 40 gallon tank. It is very important to re-check the calibration after the rebuilt units have been installed in the plane, since each plane has its own footprint. The most practical way to calibrate is to fill the tanks and then adjust the calibration screw sticking out of the front of the module untuil the fuel gauge needle drops below Full. Then gradually bring the needle back up to exactly to Full. This way you will not have the unit adjusted too much on the Full side and it will read accurately all the way to Empty. Turning the screw clockwise as you are facing it increased the fuel gauge reading and turning counter-clockwise reduces the reading. The adjustment screw has about 15 turns on it--but only a few are normally needed, If no needle movement is seen after several turns--something is wrong.
Many of the units we get back which at first were thought to be defective, were actually the result of calibration problems. In actuality the units worked O.K. once the adjustment screw was properly re-set.
Units are shipped on open invoice and may be returned for full credit if it turns out that the printed circuit board is not the problem.
Birks Aviation Products gives fast, effiecient service, fully guaranteed to give customer satisfaction.
Try rebuilt fuel gauge printed circuit boards--you'll be amazed at how accurate your Beech fuel indicator system can be. The peace of mind and comfort you get knowing you have accurate fuel gauges is more than worth the price.