Props Blowing Out - Drive Height? (Pachanga 22)
#1
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I have a 1987 Pachanga 22 with a built 502 and 1.50 Bravo 1 drive, running ~450hp. When I bought the boat, it had 1.36 upper gears and would run 74 GPS on a 3 blade 24p Mirage. The 1.36s blew up, so I replaced them with new style thick floor 1.50 gears.
Ever since the gear change, I have had prop issues. I have tried many 3 blades, and none will stay hooked up at all. It runs fairly well on a 26p Bravo 1 4 blade, but I get very little trim before it blows out as well, and will only do 68 @ 5200RPM. Right now I am running a 25p Revolution 4, which has excellent cruise and hole shot, but has even less trim and basically blows out anywhere above 4000RPM. I am probably going back to the Bravo.
What other fixes can I try? I am thinking possibly a high X dimension / drive height. My distance from the bottom of the hull to the propshaft center line is roughly 6 3/4". Should I be looking at a spacer, or maybe going to a 5 blade? Which 5 blade prop should I think about? I want to get back into the 70s.
Thanks!
Ever since the gear change, I have had prop issues. I have tried many 3 blades, and none will stay hooked up at all. It runs fairly well on a 26p Bravo 1 4 blade, but I get very little trim before it blows out as well, and will only do 68 @ 5200RPM. Right now I am running a 25p Revolution 4, which has excellent cruise and hole shot, but has even less trim and basically blows out anywhere above 4000RPM. I am probably going back to the Bravo.
What other fixes can I try? I am thinking possibly a high X dimension / drive height. My distance from the bottom of the hull to the propshaft center line is roughly 6 3/4". Should I be looking at a spacer, or maybe going to a 5 blade? Which 5 blade prop should I think about? I want to get back into the 70s.
Thanks!
#4
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From: Taunton Ma
Mirage props come in odd number pitch so it wasn't a 24, and 6 3/4" below the bottom is about the deepest bravo drive ever seen. Are you sure the prop is slipping not the cone clutch or the coupler? No way a bravo 1 prop should blow out like your describing
#5
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It may have been a 23. I had another 24p 3 blade at the time, both ran in the low 70s. I am positive it's the prop blowing out, it behaves differently with 6+ different props I have tried. The entire upper gearset is new and the coupler was also replaced at the same time as the gears.
I've tried both a 26p and 28p Bravo 1 and they are the only props I've used so far that will actually stay locked in through the whole RPM range, but they will start to blow out with not much trim up. I only have about 2/3 of a normal Bravo trim range to begin with - the boat was set up for an Alpha from the factory, and the previous owner installed stops in the trim rams to keep the drive from hitting the bottom of the swim platform at high trim.
I've tried both a 26p and 28p Bravo 1 and they are the only props I've used so far that will actually stay locked in through the whole RPM range, but they will start to blow out with not much trim up. I only have about 2/3 of a normal Bravo trim range to begin with - the boat was set up for an Alpha from the factory, and the previous owner installed stops in the trim rams to keep the drive from hitting the bottom of the swim platform at high trim.
#8
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From: Granger, Indiana
Thanks
3pointstar
#10
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From: On A Dirt Floor
I'll address both questions within this one post.
Are you experiencing blow out or more slip after you added the drive shower ?
Are you experiencing blow out or more slip after you added the drive shower ?
Are you experiencing blow out or more slip after you added the drive shower ?



