Today: Oil, Fuel, and Throttle, Oh my

Today started with a trip to Harbor Freight. My organization has been sorely lacking in the Garaggio. All of my friends who come to help gently give me reminders of that from time to time. The amount of time we spend looking for things is hugely inefficient. Last time Eric was here working on wiring with me, we both spent about a half hour finding connectors, pins, and tools. So I decided it is long past due to do something about it.

Problem is my parts bins are all full, and quite frankly I don’t like them. They are the plastic drawer type that you mount to the wall. You can’t see what you have, what you don’t have, and what is missing without pulling each individual drawer out. I opted for a “parts tray” with multiple removable bins. That way if you are working on a project you can take the whole tray, or just the few bins you need to the project and stay organized. $6 at Harbor Freight. I have ideas for how to store these organizers and keep them readily accessible. It will be a while before I build my “parts tray rack,” but we are making progress on getting organized. I filled 2 of these trays with electrical connector components and one with AN fittings.


Feeling good that I had put a bit of effort into organizing, I went back to working on the airplane. It is high time that I finished the oil cooler system. So I removed the oil filter and the right ignition so I had access to get the hose fitting into the back of the accessory case. It is a 45 degree fitting because that is all that will fit. It also ends up routing the oil line in a good direction to make it’s trek to the right side of the oil cooler. Once the fitting was in place, I could put the ignition and oil filter back on. The red cap is the oil breather and will need to be connected to a hose, which will happen soon.


Then it was a simple task of making up a hose of the right length, and test fitting. This hose still needs fire sleeve. I have 3 others that need fire sleeve as well, but I decided I would get all the hoses made up first. Then I will take them all off and finish the fire sleeve. More of a manufacturing type approach to save time.


In the previous photo you can also see that I got the hose made up that goes from the ‘little red cube’ fuel flow transducer to the fuel distribution block. That means we finally have fuel all the way from the fuel tank to the distribution block (needs fire sleeve). Only one more line to each cylinder, and the engine has fuel.

About this time, the Garaggio had a cameo appearance from Jon Meyer. He has been a bit busy with “all of the high stress life events,” at once. A new job, new baby boy, selling his house, and buying a house all within months of each other. I suppose I will not give him too much of a hard time, I really enjoyed being able to do show and tell and get him up to speed on progress. He even stayed around to help flox in the cockpit throttle and mixture mounting bulkhead.


Then Jon and I decided we should work on fuel injector lines. I previously had bent up welding rod to determine routing and length. The actual lines are ordered from AirFlow Performance since they have special braised on ends. I misplaced a few of the welding rod templates, so we started by remaking them so we don’t screw up the actual lines. True to form, I somehow screwed up the measurements on the lines that I ordered. I think I am going to have to order a few new ones that are shorter in length. At least I now know that the one going to cylinder #2 has to be shorter. So then we went on to cylinder #4.

Again, I re-bent a welding rod as practice and to validate the distance. My original measurement was… too long. But, the line that was too long for #2 fit pretty well for #4. So we bent up the injector line. The bends aren’t pretty as the only thing I have to bend these lines is a spring type bender. Additionally there are many planes and angles to consider so some tweaking was required. There is also a spec in the manual that requires .69 inches of straight line after the fitting, and then no tighter than a .5″ radius bend. To complicate things a bit more, you don’t want to run these too close to exhaust pipes to prevent boiling the fuel.

With all of these things to consider, I think we did a pretty good job with the #4 cylinder injector line. It is as far away from the exhaust as we can get while complying with the .69″ straight section coming out of the injector. These lines do run on the “cold” side of the engine, so in flight it shouldn’t be an issue. It will however make hot starts a bit more difficult. After engine shut down, I am sure the radiant heat from the exhaust will end up causing the fuel to get pretty hot. It may be worth putting a heat shield on the exhaust pipes in this area.




The good news is, we now have fuel to one of the four cylinders. Three more injector lines, and the engine will have fuel. I can’t wait for that to happen. That is a big step on the road to first engine start. 🙂

It was time for dinner by this point so I was going to be done for the day. After dinner, I couldn’t help myself. I had to go back out to the shop and get just one more thing done. I didn’t want to take the time to get another injector line bent up, so I decided I would finish the layup for the cockpit throttle and mixture cable mount. I made my homemade pre-preg and wet out a glass/carbon/glass sandwich and laid it up onto the phenolic plate. I figured the carbon may be necessary to get some rigidity. Even so, I think I will need to add a triangular rib to the bulkhead. But this layup is done.


I think I can justify calling it a day now.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: