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Crankshaft Mounted Raw Water Pump

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Old 12-28-2007 | 07:50 AM
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Default Crankshaft Mounted Raw Water Pump

Why are these not used on Merc? Seems alot easer to replace impeller and plumb.
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Old 12-28-2007 | 08:04 AM
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My 29 scarab I had there wasn't enough clearnance in front of the pulleys. I had inches left before hitting the wood to the back seat.

I'm sure in a twin applicaition with the right access hatch it would be alot easier.
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Old 12-29-2007 | 05:40 AM
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I think I might give it a try. I've got lots of room in front of the motors. Looks like I can get complete setups for around $175.00 ea.
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Old 12-29-2007 | 07:04 AM
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They dont move as much water as a merc pump ..somtimes the plumbing can look kinda funky ...Prob main reason is the clearance issue as stated ...m
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Old 12-29-2007 | 02:34 PM
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I use cam driven pumps. They work great for my 454 mags. Really cleaned up the engine and made it a lot easier to change impellers.
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Old 12-29-2007 | 08:35 PM
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I ended up installing one on a 350 I set up with closed cooling. The Merc pump rebuilt did fine with keeping the block cool but wouldn't handle the exhaust cooling. I did one of the Volvo crank mounted pumps and it was able to pump enough water to do the block and heads where the Merc wouldn't.
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Old 12-31-2007 | 09:51 AM
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Ive run them since 96 in miss river. Sandy and muddy most of the time. Changed impellers in 06 and they still looked new. No belt to jump off and over heat.
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Old 01-01-2008 | 06:00 AM
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Ok so what's involved to convert over from Merc 3 piece or 2 piece to one of these units? Are they Jabsco & is it a tough conversion?
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