Chapter 23 – Engine install

Craig Catto is well known in the pusher community for making excellent composite props.  I’m fortunate enough to have him almost in my back yard.  The only problem is his reputation is so good, he has a rather long waiting list for his props.  I wanted to make sure my prop would be ready when I need it towards the end of Summer.  I took the hour and a half drive to Mokelumne Hill, CA. in March to place my order and see his facility.

It reminded me very much of the racecar building facilities of Ron Nash in the Central New York Finger lakes region.  After driving for 3 or 4 miles down a one lane country road, I came to Craig’s home.  A nice area set back away from the California crowds where he and his son have plenty of room to ride their dirt bikes and horses.  Here is a shot of his workshop where all the magic takes place.  You would never guess that some of the UAV propellers for the US military were made here would you?


Inside, he has probably 50 props in various stages of construction.  Here are a few shots and the last is of Craig and his son, who had just jumped off his Yamaha dirt bike. 



You can see all the clipboards on the back wall full of orders!

I was running out of room in my little half “T” hanger and was fortunate enough to get a call from my landlord late in March, saying they had a full T-hanger available starting in April.  I grabbed it and moved everything down to the new hanger on the first. Luckily, it was only two doors down from my current location, so I only had to move everything about 100 feet!  Here are some shots of the new digs.


Lot’s of room now and I can leave both wings mounted at the same time.  This will be a necessity once I start mounting the engine cowlings so everything will line up correctly.  I was lucky enough that the previous tenant left a small work bench and a “college size” refrigerator behind.  It works great and will come in handy when the temps hit triple digits in the summer.

Next, I made the engine cowling mounting lips.  This involves temporarily gluing foam to the firewall and shaping it to the contour of the fuselage.  Tape over the foam for release and glass over the tape for the mounting lips.  Very EZ!  Here is a shot of that step…


Now it was time to get the engine mounted so I could start mounting the engine cowlings.  I don’t know if it was all those years of changing race car engines, but mounting this engine was a real non event.  I think the key is to use a piece of chain between the engine hoist hook and the lifting ring on the engine.  I have heard of an engine or two being dropped due to hooking the hoist hook directly into the lifting ring… about ruining your whole day!

Here are a couple of shots of the engine mounted…Notice the yellow saw horse under the plane at the landing gear. It’s there to support the back of the plane. With the engine mounted and no weight up front, the plane would flip over on its butt smashing the engine flywheel and winglets on the wings……not good!


Next, I started mounting the top engine cowling.  I quickly found out why Wayne Hicks said this exercise is like “herding cats” Every time you would line the cowling up on one wing, it would move on the other wing.  If you got both wings lined up, it didn’t fit the firewall that well, etc. Eventually, I got everything in place.  Once this was done, I used stir sticks to hold it in place and glassed the mounting lips on to the wing roots.  Here are a couple of  photos……


Taking your time and really getting everything lined up really pays off because once you start flying the plane around and other builders start looking (critiquing?) your work, a real obvious part of the assembly is how the spacing of the cowling is around the propeller hub is.  I have seen a lot of misalignment on canard aircraft……mine did come out perfectly…..I can show that off!








Next, we move onto the lower cowling…….


May 1, 2007


As mentioned above, the lower cowling was next on the list.  First, a lower NACA lip needs to be fabricated.  This will allow additional cooling air into the engine compartment.  Nothing special here….glue the foam in place, shape to match lower cowling, and glass…..


 Much the same exercise of fitting, marking, cutting, checking, fitting, etc. was done on the lower cowling just like on the upper cowling.  This was a little tougher though because now gravity was working against me.  The top cowl would rest on the engine and wing roots while I would install the camlocs.  I needed an extra hand or two to hold the lower cowling in place while trying to install the camlocs, but I became rather proficient at installing it with numerous opportunities to do so.  I didn’t take a lot of pics since it was identical to installing the top cowling.  Here is a shot of the lower cowling installed.



The plane is nose down in the photo so the lower cowling doesn’t look properly spaced, but it is…..


With both cowls in place, I had one step left to do and that was to make provisions for checking the oil without having to remove the entire cowling every time I wanted to check it.  Fortunately, the cowling came with scribe marks designating where the door is installed.  I just cut the door out, then held it in place while I glassed a flange on the back side the will serve as the lip for the camloc to hold it shut.



Next, Installation of the exhaust pipes was tackled.  I purchased them from Custom Aircraft Parts as listed in the plans.  They are stainless and the quality seems very good.  They also fit very well with no fuss or adjustment needed.  You can see the right side 2 pipes in the photo below.  They come with excess length that you cut to your desired size.



The orange plugs in the ends are just to keep foreign objects out of the engine.


The picture also shows the next step I undertook in Ch. 23, that was installing the engine cooling baffles.  Since this is an air cooled engine, this step is crucial to get right and was rather tedious, but rewarding work.  It involved tracing the plans baffles onto poster board and then taping the poster board in place on the engine.  Since the Lycoming engines and their clones are similar, the templates were close enough to use as a guide.  Yet, Nat’s plane used different size starter, alternator, and a Lycoming, vs. my ECI Clone, there were differences that had to be accounted for.  Here is a picture of the rear baffle being mocked up with the poster board. You can see I already have the cylinder head and rear main baffle in place.  Lots of small trimming and fitting around exhaust, alternator, dipstick tube, starter, etc.




Here is another shot of the detail around the starter and the lower intake runner on the right side.


As I said above, rather tedious and exacting work as shown by the pile of scrap aluminum below…….


I also made the mistake of taking a piece of scrap aluminum to the polishing wheel…..It shined up beautifully!!!  Ten hours of labor later all the baffles look like they were just sent out to be chromed…….Gorgeous!  This ten hours had nothing to do with the airworthiness of the project, yet, I am only doing something as hair brained as building an airplane once……..might as well do it to the best of my ability.  In the end, the baffling came out better than I could have expected… really looks professionally done if I do say so myself.  I was very pleased! 


Once the baffling was complete, a heat muff needs to be fabricated since this is an air-cooled engine. Can you say VW Bug?  I hear from some people the heater system works about as well as the VW too!  The muff raps around the two right side pipes.  The plans call for either stainless steel or aluminum.  I opted for the stainless steel for better durability, though it was much tougher to initially work with.  Here is the final product installed over the exhaust pipes. 



Next, I removed the engine to start work on plumbing the firewall.  Since I am using a fuel injected engine, I ordered up a high boost fuel pump from Don at Airflow performance.  Don was very helpful and genuinely a real nice guy…..I sure have met a lot of nice people in the experimental community that will go the extra mile in helping you complete your project.  This is very important since the total number of completions is somewhere around 20% industry wide and probably lower for a plans built project like this one. 


I went back and forth as to where to mount the pump. Inside the fuselage under the main spar is good for out-of –the-way and less susceptible to damage and fire, than on the engine side of the firewall, but, it is more connections that could fail and dump fuel in the fuselage. In the end, I figured, if there was going to be a failure of the fuel line somewhere near the pump, I would rather have it in the fuselage with less threat for ignition.  If there is a failure, in the engine compartment, you are guaranteed ignition with the hot exhaust pipes.  Here is a pic of the fuel pump mounted behind the rear seats under the main spar.


Next, I moved to the engine side of the firewall and installed the gascolator.  I mounted it so it is the lowest part of the entire fuel system.  All water and debris will be caught here.  The quick drain is easily accessed through the bottom NACA duct for all preflight checks. There is a flex line that goes up from the gascolator to the manual fuel pump on the engine.  The red cap all the way to the left of the photo is the bulkhead fitting from the electric boost pump and is connect to the gascolator with a hard aluminum line that I later fabricated. 


While the wings were still on, I opted to mount the oil cooler.  I decided to use the inboard right wing root area since Nat revised it here instead of the original location above the engine.  Less heat in this area, so it made sense to me……



 With the cowlings properly fitted, it was time to move on to the cosmetic fairings.  Since the cowlings have blisters on them that provide clearance for the cylinder heads on both sides, they are wider and squarer than the fuselage.  They need to be faired into the line of the fuselage for aesthetics and better aerodynamics.  This is accomplished by building a dam out of cardboard and pouring in some pour foam. 


Once this is done, comes the “artistic” part of shaping the foam.  The urethane foam sands very easily and many builders tend to over sand this area giving is a “flat” shape to the fairing.  It should have a semi round shape as per the end of the cowling.  I started off by cutting the large excess foam off with a knife and then used some more urethane foam to better shape the final fairing.  Here I am making the rough cuts……The final shape of the fairing is in the right picture just before glassing.




Next, I tackle installing the throttle and mixture cables……

Now I had to figure out how to mount the throttle and mixture cables.  I had to deviate from plans at this point because I am using the Silverhawk fuel injection unit instead of the Ellison unit called out in the plans.  I figured the Silverhawk would give better metering of fuel to each cylinder instead of the throttle body of the Ellison.  First, I needed to figure out how I was going to mount the ends of the cables.  I just bent up some 2024-t3 aluminum and mounted the mixture bracket to the firewall.



The mounting tab that the cable is anchored into is just another piece of aluminum that is riveted to the main bracket. The black wire loom is covering the CHT/EGT leads for the Grand Rapids engine monitor I am using.  You can also see the K&N airfilter I am using instead of the plans airfilter box.  We had great luck with these filters during our racing years.  Easy to clean, reusable many times over, and best of all flow a great amount of air while providing great filtering properties. 


For the throttle cable, I couldn’t mount the bracket to the firewall because the engine mount cross brace was in the way.  The front of the servo has a mounting flange for the air filter so this looked like the next best place.  Like before, I just bent up some aluminum a mounted the throttle cable.


In the photo above you can also see the plans location for the gascolator.  It is the lowest part of the fuel system and is easily checked through the NACA scoop during preflight.

Once everything was mounted and in place, it was just a matter of running fuel and oil lines to everything.  I built my own lines using Aeroquip hoses.  Once the hoses were run, I applied fire sleaving to all the lines.  Here are a few pics of the lines…



                   Fuel and oil pressure sending units


The last thing to do was to mount the prop extension and the prop.  The picture below show the 8” Saber extension and the Catto 3 bladed prop.  Both should be hanging in the Museum of Modern art. Amazing craftsmanship!










With everything in place, it was time for the first engine start.  I primed the oil lines before final attachment to the engine.  I pulled the top plugs and turned the engine over on the battery to build oil pressure. Despite being pickled for a year and a half, the engine built oil pressure within 10 seconds of spinning.  I installed the plugs and pushed the plane out of the hanger.  I had a hanger mate two hangers over who flies a Mooney come down and man the fire extinguisher. I hopped in, turned on the fuel, opened the throttle and mixture, gave it about a 2 second prime with the boost pump, moved the mixture and throttle back to close, turned on the mag and electronic ignition, yelled “Clear Prop!” and hit the starter button.  The engine came to life on the second blade!  Amazing, the LSE electronic ignition is amazing for quick starts.  This plane started better the first time ever, than my Grumman did on a good day.