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-   -   Crank-mounted water pump? (https://www.offshoreonly.com/forums/general-q/373550-crank-mounted-water-pump.html)

sutphen 30 10-04-2021 06:26 PM


Originally Posted by TomZ (Post 4807956)
That's nuts!

I'd imagine this is especially important on a Gen VI block where the water jacket to side of the block surface is thin. My 502s seeped at the head/block joint due to high water pressure. It'll no longer be an issue with closed cooling but it was a big problem when raw water cooled and at speed.

use cometic headgaskets and you won't have any weeping

TomZ 10-04-2021 07:04 PM

I hear you. The problem started before I owned it and two top-end refreshes past.

question… Isn’t it the rule to not use Cometic gaskets unless the surface can be machined per their specs? I would think that would preclude their use during a top-end refresh. Not trying to derail my own thread, it what’s the consensus?

TomZ 10-07-2021 09:58 AM

Any thoughts on what to do about the removal of the Merc pump and serpentine belt routing? The way it works in stock form, the belt goes from the circ pump then down to the raw water pump then up to the alternator. Removing the raw water pump… can I just go to the alternator or should I get an idler? I thought about leaving the pump assembly (sans impeller) on the engine, but honestly, I'd like to sell them to recoup some of the cost.

TomZ 10-07-2021 11:22 AM

Looks like this is acceptable...

https://cimg8.ibsrv.net/gimg/www.off...8629cf2ad4.jpg
This is a 5.7L but the routing is basically spot-on for the 454/502 MPI accessory drive. They go straight across to the alternator and then back to the tensioner. The tensioner is much larger on this setup.

F-2 Speedy 10-07-2021 11:38 AM

I used the Felpro MLS when I added the Whipples, no machining done

TomZ 10-07-2021 08:56 PM

I got a pair of 3/8 billet spacer plates in from Speedway Motors today. They’re needed to make up some of the depth needed to keep the pump housing for hitting the pulley. I took everything up to Lowes to get some spacer/bushings. 3/8 inside, 1/2 outside. I’ll need to cut them down but they center the bolts perfectly. This should be easy to put together. I’ll get some pics as I’m putting it together along with part numbers used to put it all together.

SB 10-07-2021 09:41 PM

Uh oh, he said “easy.” :poopoo: :angry-smiley-038: :lolhit:

TomZ 10-08-2021 07:40 AM

Famous last words!

compedgemarine 10-08-2021 07:55 AM

the only "easy" way to go boating is to give someone a $100 for gas and ride with them. at the end of the day you go home while they deal with the boat and you rode around on the same boat they are spending all their time fixing. but seriously, I work on several boats that have a crank driven pump and they are so much easier to deal with in cramped compartments. as for water flow, never seen an issue, heck, my jet boat only had a 3/4 hose from the pump cooling the engine and as hard as it got run the temp never climbed with a crossover and no thermostat.

TomZ 10-09-2021 01:12 PM

So much for easy… but not the way you’d think.

I landed bad when I jumped off the back of the boat last weekend. I knew I did something wrong because I felt the front of my left foot stretch much more than it should. Started out limping Saturday night and now it’s all jacked up… I can barely walk on it. I went out to dinner with my girl last night and couldn’t even get a flip-flip on it let alone a shoe. Guess I’ll be off of it for a while. Shoot.


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