Thruhull pickups
08-22-2009, 12:42 PM
#11
Crazy Energy
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I have never had sucess with those thru-hull pickups. You should consider a transom mounted pickups with a lead in groove and install pop-off valves on the strainer to bleed off excess pressure. I used a 1.25" diameter pipe wrapped in sand paper to create the lead in groove. It is 5" long and about 3/8" deep. The pickup does not extend past the bottom of the hull. I would also either block off the the drive fed pickups at the inner transom plate. If they pull air, you will continue to have pressure problems. You should also weld a center plate inside the pickup to prevent larger pieces of debris from clogging the pickup.
Last edited by Velocity Vector; 08-22-2009 at 12:44 PM.
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.I Redesing the one on the left
08-22-2009, 07:44 PM
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Those sportmasters will support enough water, they have to be modified on the openings, you can do it with a die grinder or better tear the lowers down and set them up in a milling machine and end mill the inlets larger and deeper lead-in grooves, if you have a step bottom, I can bet you are getting air in the water system, if so you need to dump the air from the top of the strainers to below the water-line when the boat is not on plane. you can run on 15 psi water press, but, without the air, they will support at least 800 HP for sure. I had a 2004 Top Gun with the same problems. Air is still going to be there on a stepped bottom.
08-22-2009, 10:48 PM
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Those sportmasters will support enough water, they have to be modified on the openings, you can do it with a die grinder or better tear the lowers down and set them up in a milling machine and end mill the inlets larger and deeper lead-in grooves, if you have a step bottom, I can bet you are getting air in the water system, if so you need to dump the air from the top of the strainers to below the water-line when the boat is not on plane. you can run on 15 psi water press, but, without the air, they will support at least 800 HP for sure. I had a 2004 Top Gun with the same problems. Air is still going to be there on a stepped bottom.
Last edited by Velocity Vector; 08-22-2009 at 10:51 PM.
08-26-2009, 12:45 AM
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I would rather have transom pickups but to get them installed I'm thinking I would have to pull headers to get at them is why I choose the thru hull's. I'll be 21 inches in front of the transom. Do you have to pull the drive to get to the inner transom plate? I also have 12" Imco extension boxes.
