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Bigger alternator belt???

rv6ehguy

Well Known Member
Hi folks,
I’m currently installing the baffles on my RV6A build. I had to re-jig my prop governor oil line to fit through the 1” drilled hole in my right baffle ramp. Now my alternator gets pushed against the oil line when I install the alternator belt.
Does the brain storm here see any reason not to put a bigger belt on (1”-1.5”). This would result in the alternator not being pulled into the oil line. The relationship between the two pulleys does not change. I can’t see any down side here but if I’m missing something, please let me know. Cheers .
John Van Lieshout
RV6A QB 85%
AeroSport Power IO-375 195hp
 
If you have room on the adjusting arm. Go for it. No reason not to have another belt hanging on the wall just in case the lawn mower needs it.
Ha Ha. Napa aviation helper is ready to take your money.
Just make a note in your records as to the part number so as to get the right size next time.
Yes I have an RV-6A also and just rebelted when prop overhaul.
Art
 
Is your cowling installed? Usually a longer belt results in the alternator rubbing against the cowl.
 
Exactly what he said.. a longer belt may have you putting a blister on the cowl.

Yep. My original belt (supplied by B&C) was long enough to cause the pulley to rub against the cowl when pulling any amount of G's. I found the problem early and swapped to a shorter belt before I had any meaningful damage.

So... Yes, you may be able to swap the belt, but make sure you have clearance between the alternator pulley and cowl, and make sure you do a bit of G-pulling on early test flights to validate your choice. Better to find the problem on a routine check than when the pulley cuts a hole in the cowl.
 
Hi folks,
I’m currently installing the baffles on my RV6A build. I had to re-jig my prop governor oil line to fit through the 1” drilled hole in my right baffle ramp. Now my alternator gets pushed against the oil line when I install the alternator belt.
Does the brain storm here see any reason not to put a bigger belt on (1”-1.5”). This would result in the alternator not being pulled into the oil line. The relationship between the two pulleys does not change. I can’t see any down side here but if I’m missing something, please let me know. Cheers .
John Van Lieshout
RV6A QB 85%
AeroSport Power IO-375 195hp

It sounds like you have a plane power. I bent my line closer to the engine, the clearance between alternator housing and the line is 2mm, and nothing has touched. If you want a longer belt - 1/2" will move it 1/4" - a huge amount. You may reach the end of the adjustment as the belt breaks in though.
 
bigger belt should work.

Thanks folks. I think a bigger belt is going to work. I have had my cowling on and as I recall, there was plenty of room but I will recheck. I also have room on the swing arm, which is why I thought I could go to a bigger belt. I do have a Plane Power alternator and I will try a belt that is 1/2 inch bigger. Going to a 1" bigger belt was just a guess but as usual, this forum eliminates most of the guess work. Thanks again.
John Van Lieshout
RV6A QB 85%
AeroSport Power IO-375 195hp
 
Alternator Belt Fit

in conjunction w/prop overhaul--- replacing 15305 alternator belt in-kind with another 15305. Original belt was smooth top and bottom no cogs (lost -- long story). This one has a cogged bottom.

I'm told it's "customary" for the the belt not to sit so proud in the sheave and question about the cogged belt. Appears from some quick searches that the cogged belt is a tiny bit more efficient.

Seems to flex about 1/4" easily with thumb and alternator sheave slips under 12+/- 1-2 ft lb., so I'm thinking the tension is totally appropriate.

Thoughts?
 

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