Final items before the run?
Sis returning to solid ground after her time up on the Beech Jack feels good – I can give her my usual pat and kiss hello on the spinner again.
Sis is a 1947 Beechcraft Bonanza model 35, one of the first 1000 off the assembly line. For all intents and purposes, she is my big sister as I have grown up flying with her and now am her caretaker.
The restorer has been reviewing the engine break-in procedure in preparation for engine runs over the past week or so. Christmas is just around the corner, temperatures have dropped but are still not below freezing and snow has yet to make its way into forecasts. While there is so much going on, I guess that’s my light at the end of the tunnel.
The restorer hooked up the fuel injection system on Sis as the baffles were installed. Focusing on other areas, the system was inspected and confirmed to work before the spark plug wires were reinserted.
Sis has been sitting with both her main tanks full of fuel and a few gallons in the auxiliary tank as well. The main tanks are used for all phases of flight, and the auxiliary fuel is used to supplement.
The restorer indicated the tanks being full of fuel has probably helped. Moisture and debris can get into the tanks if the fuel caps are not secure. Before every flight, the fuel in tanks is inspected for water and debris to ensure the engine will run properly.
This is even more important as the first run after an extended time sitting.
The restorer brought out a clean white bucket to drain a test amount of fuel from each tank – a procedure called sumping – to look for any water or foreign matter in the fuel.
The fuel, 100LL, is tinted blue in this case, water can look like bubbles floating in fuel.
Not too bad! Looked good after the time sitting.
Fuel contamination can lead to engine roughness or engine quitting.
Putting the battery back into Sis is another indication of progress – sitting in the pilot’s seat once again felt strange and good at the same time.
Remembering where things are in Sis is taking a moment or two. While I have been in the left seat for the gear swing and checking the brakes after servicing and bleeding, It still doesn’t feel entirely real.
The previous day, we added a CO detector to the panel and confirmed the pitot tube was free of blockages.
The restorer is outside the airplane, the engine cowl is open to see everything. I am sitting in the left seat to turn switches and call out readings as needed.
After confirming that one of the fuel tanks is indicated in the selector, the restorer has me turn on the battery master and boost pump and wait for fuel to head out to the injectors. The JPI, the engine monitoring instrument, comes online to show fuel pressure and flow, or it would if fuel was moving.
Limiting boost pump operation to 15 seconds for first runs as he is concerned about burning out the pump if fuel does not flow properly.
Sis has been sitting for a long time, it may take some extra persuasion to get fuel to move through the system.
The restorer next has me use the wobble pump to supplement the boost pump during troubleshooting to hopefully extend battery life. There is still no indication of fuel flow on JPI or visual of fuel to the fuel injectors.
The restorer said it’s acting like it’s lost its prime but was pleased there is no fuel leaking anywhere.
Temperatures are dropping and the sun has already set, so we call it a day. The restorer is happy with everything we got done – even with the fuel not going as expected.
We took the moment to gather up materials that were no longer needed at Sis’ hangar and loaded them into our car for the drive to the restorer’s hangar.
While unloading the no longer needed items at the restorers’ hangar, he looked around for something to help prime the boost pump.
Finding a small squeeze bottle with a nozzle fit the bill nicely.
We headed back to the house and the restorer reviewed materials for how to move fuel through Sis.
He confirmed the boost pump can be engaged for a longer period of time than we previously thought and planned on using the squeeze bottle to squirt fuel directly into the pump to reprime it.
Sitting back in the left seat of Sis for the second day in a row, we reviewed the checklist I created with my old chief pilot after the fuel injection was installed. It indicated about 6 seconds were needed before fuel pressure would be showing on the engine monitor within the JPI.
The restorer had looked at some other items within the boost pump procedures and said we could extend the time for the pump which should give better results.
I don’t remember using the wobble pump at all on the second day….
The restorer filled the squeeze bottle with fuel and squirted it into the inlet line for the boost pump then had me start the boost pump.
We repeated several times until fuel is coming out of the injectors and running out of the engine.
Monitoring the JPI, I saw fuel pressure finally coming through the system and relayed to the restorer standing just outside the window.
Once fuel is within the injectors, the restorer is pleased with the procedure and says we are ready to move on to other tasks.
For me, it’s adding oil to the engine. During engine break-in, a blend of mineral oil is used. Depending on the temperature, two different types could be used. 40 weight or 50 weight with 40 weight used in cooler temperatures.
The weather over the next week still looks pretty good. Unfortunately, we will be out of town for the holidays. Temperatures will start dropping when we get back. The decision to put in 40-weight mineral oil has been made with that in mind.
While monitoring my progress with adding oil, the restorer connects the spark plugs to their wires.
Each day, we have been working slowly towards getting Sis back in the air. Each task completed is getting us closer to that goal.
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