40' Outlaw Upgrades - Twin 900Sc to 1000hp Duramax Diesels
#1151
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Join Date: Aug 2012
Location: Collierville, TN and Pickwick Lake
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I'm going next week to try and diagnose a 40' cat with that exact setup. It's yet to ever get up on plane since being rigged many years ago. Once running, I'll spot it a 1/4 mile and then suck that yellow paint right off it when flying by.. LOL
These pump issues are minimal on the grand scale of things. And not to brag, but my hardware ain't even got warmed up yet. But it's kinda getting a little old doing R&D for others on our dime. We take what everyone says is best of the best, then we find what everyone missed.. I've spent over 10yrs playing with these engines in boats, without 1/50th the budget of any other marine powertrain manufacture. The closest thing out there is the SMD stock internals Duramax rated at 500hp with some marine manifolds and $20 worth of white anti-oxidizing paint. Pound for pound foot or torque, 1350 QC4v don't even match these puppies with 9,0l and 200hr rebuild requirements. I finally saw one torn apart last week, and to my amazement, the rods were NOT gold plated as I had imagined..
So our options today are pretty much these. Drop in another 12mil stroker pump that can fuel 1000HP and then get technical on what it doesn't like in a boat. In 6yrs, only two have failed, I claim both.. LOL Next option, we can step down to a 10mil pump that's good to about 850hp, and see how they hold up. I have ran one in a boat setup for little more hours than on this build. But still limits our max power in exchange for some hours on the meter, maybe.. Third, go dual stock CP3 pumps. Those don't seem to have a problem in boats, but requires some extra electronics, lines, and moving things around on front of the engines.
Tomorrow I'm going to have an in person chat with the pump manufacture we are using now and see what they are will to bring to the table. My thought is we give em another shot, and then send both pumps back for inspection after a dozen hours on the clock. Maybe add a little lube to the fuel as they suggest, and see if we can learn why they don't like life at 5000RPM for more than a few seconds.
These pump issues are minimal on the grand scale of things. And not to brag, but my hardware ain't even got warmed up yet. But it's kinda getting a little old doing R&D for others on our dime. We take what everyone says is best of the best, then we find what everyone missed.. I've spent over 10yrs playing with these engines in boats, without 1/50th the budget of any other marine powertrain manufacture. The closest thing out there is the SMD stock internals Duramax rated at 500hp with some marine manifolds and $20 worth of white anti-oxidizing paint. Pound for pound foot or torque, 1350 QC4v don't even match these puppies with 9,0l and 200hr rebuild requirements. I finally saw one torn apart last week, and to my amazement, the rods were NOT gold plated as I had imagined..
So our options today are pretty much these. Drop in another 12mil stroker pump that can fuel 1000HP and then get technical on what it doesn't like in a boat. In 6yrs, only two have failed, I claim both.. LOL Next option, we can step down to a 10mil pump that's good to about 850hp, and see how they hold up. I have ran one in a boat setup for little more hours than on this build. But still limits our max power in exchange for some hours on the meter, maybe.. Third, go dual stock CP3 pumps. Those don't seem to have a problem in boats, but requires some extra electronics, lines, and moving things around on front of the engines.
Tomorrow I'm going to have an in person chat with the pump manufacture we are using now and see what they are will to bring to the table. My thought is we give em another shot, and then send both pumps back for inspection after a dozen hours on the clock. Maybe add a little lube to the fuel as they suggest, and see if we can learn why they don't like life at 5000RPM for more than a few seconds.
Priceless.
Last edited by payuppsucker; 04-05-2021 at 05:21 AM.
#1152
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Here is a few pics from the Charlotte Harbor run last weekend. Was first time for the event, but still a nice turn out on short notice. Curious wet spot on the side of that bridge I noticed. 













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2187 (04-13-2021)
#1155
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Took a few days off to take care of some other biz, and let the diesel pump gurus sort out why we had 2 failures so close together. Believe they have that sorted out now, so I moved to swapping the drives. Plan is figure out the extension box setup again. Try to start with the prop shafts as close to where they are running now. So yesterday we pulled Stbd unit off and split extension box from transom assembly to check the dimensions. As figured, the Wesimann transom assembly doesn't match up to #6 dimensions. So gotta start from scratch again.
Looking for a good pair of #6 extension boxes if anyone has some laying around. I have the patterns in CAD to make new end plates if need be, but would really save time just bolting some up.




Looking for a good pair of #6 extension boxes if anyone has some laying around. I have the patterns in CAD to make new end plates if need be, but would really save time just bolting some up.




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#1159
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No the transom has old 6 pattern factory.