32 LRC prop pitch

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Jwood1
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32 LRC prop pitch

Post by Jwood1 »

I'm curious what prop size and pitch are on your PDQ 32 LRC and what rpm are you getting WOT? My 32 LRC has a three blade prop, 15" diameter, 12 pitch. It only gets 2800 rpm WOT. The Yanmar 2GM20's are supposed to go to 3600 rpm max and develop max HP at 3400. Thus, I think I'm overproped.
Terrapin
1997 PDQ 32 LRC #26
Punta Gorda, FL

http://terrapinsailing.com/
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chicagocat
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Re: 32 LRC prop pitch

Post by chicagocat »

I would say you are overpropped. I have a PDQ 36 LRC with 2GM20's and WOT is more like at least 3200. I can't recall prop size and pitch, but I'll look at the docs next time I'm at the boat.
PDQ 36052 - 1996 LRC - "Anne Z" - Chicago
and 2001 PDQ 36 Classic (Tall Rig)- "Cat Tales" - Punta Gorda, FL
Jwood1
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Re: 32 LRC prop pitch

Post by Jwood1 »

Update,
I used Coastal Prop in Ft Myers. The props on my 32 LRC are three bladed, 15 x 12. With Yanmar 2GM20s it was only getting 2800 rpm at WOT, clean bottom, clean props. The engines would also smoke. Randy at Coastal performed a calculation based on the max RPM of the 2GM20s and a transmission gear ratio of 2.62:1. He calculated that I need to reduce the pitch from 12 to 9. They did the re-pitching and balancing for $135.00 each. The re-pitched props work perfectly. I can now get almost 3600 at WOT and comfortably cruise at 3200 rpm, much closer to the peak HP of the engines. The engines run much more smoothly and no more smoke! This also allows me to "exercise" the diesels at WOT periodically to burn off carbon deposits, something strongly recommended by diesel mechanics.
Terrapin
1997 PDQ 32 LRC #26
Punta Gorda, FL

http://terrapinsailing.com/
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