Can't hear my blowers whine. Stumped
#1
Hey pros of the blower motors. Took delivery of my first pair of blower motors. I don't really no blower whine out of them, they idle and run nice. A hick up with my electric fuel pumps seeming to just loose pressure once n while. Like loosing prime. These are 540s with I believe to be bm 250 s. Duel carbed. I just don't hear any blower noise, whine. Gauges don't seem to move. One actually goes back words. And then up to zero. Is there any tricks to know if I'm actually building boost. ? Any help. My buddy thunder might help a brother out :-)))). Thanks all. Boat did run 83 gps though. 38 top gun.
Last edited by ROB FREEMAN; 07-20-2015 at 06:57 PM.
#4
Registered

Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
Rob, those serpentine belt systems, are normally pretty quiet, until you get to WFO. Then, you should be hearing some whining from the blowers. Boost gauge should be registering something to the positive side. Unless the belts are slipping, blowers extremely worn out, or carbs not opening all the way...Heres what my little blowers sounded like when I had the stock sunpad setup. Much louder now with race hatches.
https://www.youtube.com/watch?v=n166ndUEcWc
#5
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Joined: Aug 2014
Posts: 250
Likes: 37
From: MN
250's are a fairly small blower for a 540 but they will build boost.
As far as speed I saw you were seeing 82 ish on a flat bottom top gun. From my experience that is about right. A few years back a buddy had a flat bottom top gun w 540 and small blowers, ext boxes and it ran 83-84 top #'s
As far as speed I saw you were seeing 82 ish on a flat bottom top gun. From my experience that is about right. A few years back a buddy had a flat bottom top gun w 540 and small blowers, ext boxes and it ran 83-84 top #'s
#8
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Joined: Jul 2007
Posts: 3,648
Likes: 32
From: Oneida Lake NY
My 256s are deafening, and they are under the padded hatches with no scoops. This video is a go pro on the transom, in a waterproof housing. The blower whine dominates the CMI exhaust sound in my cockpit. I would say something is not right. https://www.youtube.com/watch?v=ofkLbvnTlps
#9
I dont think i here my 250's either. but i have dry exhaust so maybe that drowns them out. With this new hatch I'm getting there will be a large air intake in front, maybe that will allow more noise to come through.



