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About a year and a half ago I bought a beautifully completed Bearhawk 4 Place from Gavin Chester in Nanaimo BC. While Gavin did a spectacular job building the machine, almost right away I felt it was lacking a little something in the performance department. My IO-360 "200hp" Bearhawk wasn't even meeting BH book specs for the 180hp Bearhawk. It was to the point that a fully loaded 150hp C172 would pass me in the climb both laterally and vertically. I truly did feel bad when the Flight Chops Episode came out where the guys in the Maule and the C180 were having a good laugh at my inability to keep up. Enough was enough. I use this machine for flying in the mountains and into short gravel strips and gravel bars on the river. The lack of obstacle climb in my IO-360 BH was really disappointing and I have a very strong suspicion that for whatever reason the engine was not truly putting out 200hp.
(as it turns out after tearing down the io-360, the crank was installed 1 tooth off which threw all the timing out so for a year and a half I was flying around in a 145hp Bearhawk)
That left me with a decision.
1. Sell the BH and get something that met my performance expectations.
2. Build on the beautiful airframe that Gavin put together and make it into the machine that I want to fly.
Option 1 would have been cheaper but option 2 was the winner only becasue I was starting with such a great base.
I got my 260hp IO-540 engine from Aero Atellier in Quebec Canada and traded in my 360 core as part of the deal. Since I don't know if the engine was doing what it was supposed to I want some separation between me and it hence no private sale. I had originally put a deposit down on a Bob 540 but with the Canadian dollar exchange rate where it is and with what is going on politically south of the 49th I chose to keep my money in Canada. When I found a engine shop in Canada that came highly recommended and only needed a 6 week lead time I went with it and shortly thereafter I was the proud owner of a IO-540.
I gave the job to the local aircraft maintenance shop to complete the swap. Yes I could have tried to do it myself but my time is better spent working some overtime to pay the shop bill. That and I have an airplane for one reason, to fly. The plane went in on March 25th and the job took 14 weeks. It probably could have been quicker but there were some hickups along the way. After some minor cowl modifications and a modification to the BH factory engine mount the engine was installed. The whole process was a complete nightmare (as many of you alluded to in my post a year ago when I asked about the conversion on this forum a year ago). The conversion was expensive and cost me a friendship with my local mechanic. I learned a ton about aircraft engines and what happens firewall forward but I did learn that many aircraft maintenance engineers are not engineers at all but merely tool owners with a business license and are completely dumbfounded and lost if they don't have an aircraft service manual or instructions to follow.
The number of things that I found wrong with the installation after I was told it was done on my initial inspection was astounding. From fuel lines hooked up backwards to engine control cables and the entire fuel servo mounted in the wrong direction and components that had no business being bolted to that engine, the list goes on. I found the errors and they have been rectified. Having lost trust and faith in my local shop I brought in another friend and engineer to have a once over on everything. After a few tweaks to the installation I took her for her first flight today.
All I can say is that I was not disappointed. Its hard to get a gauge on the new performance in just the first flight but what I can say is that it ran well and a few differences were noticed immediately.
It was 22C outside and the plane lept off the ground by the time i got the throttle to the firewall, maybe 300ft and I wasn't trying. The initial climb was in the neighborhood of 2200fpm vs the 600-750fpm that I got on the old installation and my indicated airspeed at 75% power was 128kts vs the 100kts I would see on the old engine.
I will report back as I get more data but on this flight I was too focused on the engine gauges to really take note of much else. While I was disappointed in the BH performance when I initially bought the plane I think with this new upgrade things are about to get a whole lot more fun especially for the type of flying that I like to do.
I'm finally a real proud Bearhawk owner!
(as it turns out after tearing down the io-360, the crank was installed 1 tooth off which threw all the timing out so for a year and a half I was flying around in a 145hp Bearhawk)
That left me with a decision.
1. Sell the BH and get something that met my performance expectations.
2. Build on the beautiful airframe that Gavin put together and make it into the machine that I want to fly.
Option 1 would have been cheaper but option 2 was the winner only becasue I was starting with such a great base.
I got my 260hp IO-540 engine from Aero Atellier in Quebec Canada and traded in my 360 core as part of the deal. Since I don't know if the engine was doing what it was supposed to I want some separation between me and it hence no private sale. I had originally put a deposit down on a Bob 540 but with the Canadian dollar exchange rate where it is and with what is going on politically south of the 49th I chose to keep my money in Canada. When I found a engine shop in Canada that came highly recommended and only needed a 6 week lead time I went with it and shortly thereafter I was the proud owner of a IO-540.
I gave the job to the local aircraft maintenance shop to complete the swap. Yes I could have tried to do it myself but my time is better spent working some overtime to pay the shop bill. That and I have an airplane for one reason, to fly. The plane went in on March 25th and the job took 14 weeks. It probably could have been quicker but there were some hickups along the way. After some minor cowl modifications and a modification to the BH factory engine mount the engine was installed. The whole process was a complete nightmare (as many of you alluded to in my post a year ago when I asked about the conversion on this forum a year ago). The conversion was expensive and cost me a friendship with my local mechanic. I learned a ton about aircraft engines and what happens firewall forward but I did learn that many aircraft maintenance engineers are not engineers at all but merely tool owners with a business license and are completely dumbfounded and lost if they don't have an aircraft service manual or instructions to follow.
The number of things that I found wrong with the installation after I was told it was done on my initial inspection was astounding. From fuel lines hooked up backwards to engine control cables and the entire fuel servo mounted in the wrong direction and components that had no business being bolted to that engine, the list goes on. I found the errors and they have been rectified. Having lost trust and faith in my local shop I brought in another friend and engineer to have a once over on everything. After a few tweaks to the installation I took her for her first flight today.
All I can say is that I was not disappointed. Its hard to get a gauge on the new performance in just the first flight but what I can say is that it ran well and a few differences were noticed immediately.
It was 22C outside and the plane lept off the ground by the time i got the throttle to the firewall, maybe 300ft and I wasn't trying. The initial climb was in the neighborhood of 2200fpm vs the 600-750fpm that I got on the old installation and my indicated airspeed at 75% power was 128kts vs the 100kts I would see on the old engine.
I will report back as I get more data but on this flight I was too focused on the engine gauges to really take note of much else. While I was disappointed in the BH performance when I initially bought the plane I think with this new upgrade things are about to get a whole lot more fun especially for the type of flying that I like to do.
I'm finally a real proud Bearhawk owner!
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