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Quote:

Originally Posted by MER Performance (Post 2937175)

Super clean set-up! What size are the strainers? Why, did you go to a 1" longer lower? Becareful testing this,you could very easily cook the cylinder heads. Read the temp with a temp gun on the cylinder heads in all 4corners of the manifold at the water outlets, frontand rear. Is your oil temp climbing also and not coming down? I just went through a very costly problem on a top gun. This was posted on the other site SOS under 38 Top Gun cooling problems, if you want to look at it. http://www.seriousoffshore.com/forum...ead.php?t=8435

Thanks for the reply, We just installed the motors and drives, MY sports masters are 1" shorter not longer, I have been carefull not to exceed the temps, oil temp is good when engines are @ 140 but when it climbes the oil temp climbes too. Here are what the strainers looks like I'm useing two of them and my flush kit. When I hook the water hose up to run the engines the hose doesn't collaps like it did on another boat I had with strainer. Like its not sucking to hard. I thought my flush kit might be sucking air so I by-passed it and it does the same thing not sucking hard so I hooked it back up.

Quote:

Originally Posted by aTX427 (Post 2937234)

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.

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.

this is what Im doing,the thru the knotch or botton would of benn cheaper:(.I Redesing the one on the left:drink:

Quote:

Originally Posted by Strip Poker 388 (Post 2937371)

this is what Im doing,the thru the knotch or botton would of benn cheaper:(.I Redesing the one on the left:drink:

Those are nice, looks like you been doing some ciphering on the patteren.

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.

Quote:

Originally Posted by MER Performance (Post 2937436)

This is a pad bottom, no steps. I looked at the hose today from the lower pickups on the drive, what size is that hose, looked like 1"? It acts like air to me too.

Quote:

Originally Posted by Velocity Vector (Post 2937278)

You should be able to access the drive water block off through the access plate of the extension box. You will still probably need to channel the hull to feed the through hull pickup. Just an idea, but you may consider trading your sportmaster lowers for Imco lowers. They flow way more water and can be ported if you still need more flow.