International Stinson Club Knowledge Base
The later & current production Bedford alternators are mfg. from Nippon-Denso 100 mm alternator cores are not STC’d but come with a detailed instructions & enough FAA far 23 data to install by 337 field approval. Stan Bedford has recently sold the entire line to ECI of San Antonio Tx. ECI has been working the paper to FAA PMA & STC the entire product line for over a year now. Classic Aire inc has approached ECI and hopes to be the exclusive distributor of the new line of alternator products based on the Bedford technology.
As of November 2003 , current market costs of the Bedford SCB201F alternator with hub, absorber & drive gear is $795.00. for those who want to use the hub, absorber & gear from the old generator may do so, the bare alternator has recently been sold for $595.00. There are still a few units available that are from Bedford’s earlier manufacturing. They have been and still are in high demand.
The SCB 201 F is the cream of the crop of Franklin after market alternators in technology , fit, function, & its light. wt. of 6.5 lbs.
From David Pasquale facebook post dated 09Dec19
I contacted Susan at Franklin Engine Company. She put me in touch with Bruce Kown who had a new alternator kit which I purchased.
The next hurdle was getting the alternator approved for installation on the Culver LFA. I had a prior field approval of the same alternator installed on the same model airplane and engine. Unfortunately my FSDO would not use the field approval because they were concerned with increasing the output of the electrical system from 8amps (original generator) to 25amps (new alternator)
This lead me to contact a DER. As some of you know DER’s are specialized, you have to find the right one to work on your project. Many phone calls got me to Terry Bowden. Terry informed me that he could help me but needed engineering data that would show the load placed on the engine by the alternator. This lead me on a several month saga trying to get the data.
The alternator used in the Stan Bedford STC is a Denso 021080-0760 alternator. Through my search I found that this alternator has at least 12 different part numbers. Some of the part numbers signify a slight variation like a different pulley of different housing and some are just a superseded number. Denso field support only had part of the information I needed and had me contact end users of the alternator because they felt some of the data was proprietary. I contacted Ishikawajima, Yanmar America, Iseke and Massy Ferguson to name a few. All told me what I originally thought, the required information is owned by Denso.
Multiple calls to Denso field support in between calls to end users and final call where I insisted they give up an engineering contact got me a phone number for Denso America’s engineering office in Michigan. The only problem is you need to have a contact name in order to get beyond the receptionist. After multiple calls to the receptionist at Denso I finally convinced one to connect me with an engineer. Unfortunately the engineer I was connected to was not in electrical systems. He asked me to send him the info anyway and he would try to get me to the right person. Several weeks went by with no response. I called back and this time a Japanese person answered the phone. They could only speak enough English to tell me that the guy I was looking for was out of the office I had the wrong department, I was connected to ignition systems engineering. I took the information I had and returned to Google. My Google search lead me to LinkedIn where I found the profile of the engineer I talked to. At this point I realized he was connected to other LinkedIn profiles for people at Denso America. I started adjusting my search and found a LinkedIn profile that was the head of 12volt charging systems engineering at Denso America in Michigan. Unfortunately LinkedIn would not give me a name because they were outside my circle. Fortunately Google was happy to reveal the person’s name with the exact wording of the title. I called the Denso America and left a voicemail for the engineer.
He had one of the engineers working under him get in touch with me and I received the requested information which I forwarded to Terry Bowden. Terry provided the paperwork approving the alternator on the Culver LFA I’m working on. The installation itself is very slick. It weighs about half as much as the old generator. The output is limited by the engine speed. The alternator is capable of putting out 45 amps of current but needs to turn faster than what the 90hp Franklin will do. At red line engine RPM the alternator will put out around 25 amps and do so by placing less load on the engine than the original generator did to produce 8 amps. I still have to finish the airplane which has been a long term project. Hopefully I will be able to get it flying by next summer.