Alternator pulley hits cowl

[Mikeyb]

The alternator pulley on my B&C 40A alternator started touching the cowl during 4G pulls after a year of flying. The mounts are the Barry units sold by vans and are installed properly and tight. I can’t see the sag but it didn’t happen in phase 1 testing. I did tighten the alternator once. On the ground it looked like there was plenty of clearance. I found a thread in the RV4 forum discussing it. I replaced the 7360 belt with a 7350 and cut an inch off the top side of the tensioning arm. No big deal but removing the prop is invasive and not fun. If you are building something similar do it now.

 

[rv8ch]

Great tip, Mike. I didn't think of cutting that arm at the top and reducing the belt size.

What I did was changed the pulley to a slightly larger one, which slowed down the alternator a bit, and moved it up.

http://www.rv8.ch/alternator-pulley-change/


Your method looks better.

 

[Mikeyb]

Thanks but as usual someone else on VAF solved it. I don’t think there is a single RV8 problem that some contributor including you that has probably solved it three different ways.