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Friday, June 8, 2012

Alternator blast tube and continued baffle seals

Updated:  After some advice from a fellow builder, I contacted Plane Power and got clarification on the blast tube.  They do indicate that it should be either across the back, or from the back.  I will modify my set up a bit to change the blast tube as initially I have it blowing on where air comes out from the internal fans.  The directions aren't very clear here so I am glad I asked, but my new blast tube will take a but of a "U" shape to bring the air more towards the back of the allternator.  New pics to come..

I took a couple minutes to think about how to secure the alternator blast tube.   Many times on experimental aircraft people over engineer the solution as I know I have done in the past..  In this case its always better to keep it as simple as possible.  Here I simply took some safety wire and a few loops secured the tube to the alternator strut.  It will hold it secure forever and is targeting the rear part of the alternator and regulator.   Seems good to me.

UPDATE:  I understand now that the blast tube is supposed to blow on the back of the alternator, so I have now created a reverse loop on the blast tube bringing air in directly from the back.   I'll try to get photos soon.

Also, I started messing around with the rubber seals again on the baffles.   I’m making progress, but not sure I am comfortable with it yet.  I’ll keep plugging away this weekend.


  1. I'm guessing the blast tube keeps the alternator cool right?

    1. Yup ! Actually, it keeps the alternator cool, but more importantly the regulator which in my case is part of the alternator.. Some people don't put blast tubes here, but its recommended and typically you will get a longer more reliable life out of your alternator.


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