Jabsco Raw Water Pump Improvements

The photos are of my spare raw water pump. My engine is a Perkins 6-354 Range 4. I have replaced all my slotted brass cover plate screws with SS allen screws, and made an allen driver with the correct length for my pump mounting position. I have also made an impeller removal tool that works well for my pump location.

Dave, is there any issue with mixing metals?

Very nice. Don't know why Jabsco doesn't use Allen screws.

Good for you. I replaced mine with hex screws and use a nut driver. Saves a lot of time and frustration.

Max Simmons said:

Dave, is there any issue with mixing metals?

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The original screws were brass, threaded into a bronze pump body, so I think stainless is actually an improvement.
I made a crude video for YouTube titled perkins marine engine raw water pump improvements.

Be worth using duralac, tefgel or similar on those dissimilar metal threads IMHO.

Greetings,
Mr. HM. Kudos on the removal "tool". I like it!

HopCar said:

Very nice. Don't know why Jabsco doesn't use Allen screws.

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You can always find a flat screwdriver. Not so an Allen wrench.

Slotted screws have not been an issue for me on my pump but I suppose if access was more difficult, Allen screws might make it easier to remove and replace the screws.

WesK said:

You can always find a flat screwdriver. Not so an Allen wrench.

Slotted screws have not been an issue for me on my pump but I suppose if access was more difficult, Allen screws might make it easier to remove and replace the screws.

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Exactly. I also switched to SS Allen bolts. There just wasn't room to get a flat screwdriver in there, never mind a screwdriver and a hand to turn it. An Allen driver on a ratchet works great.

As it turned out, my impeller puller fit, just barely, so no tool mod was required. But I like the idea.

This changes an impeller swap job from a day-long affair involving turning my knuckles into hamburger, into a merely unpleasant job involving an uncomfortable position outboard of one engine.

Also the knurled cap screws make it easy to start and snug by hand.

Nice job. I like the removal tool also. Am I reading the Jabsco model number right 9990-1?
I need to get a back up pump for my old Obedorfer pump that's obsolete.

Pack Mule said:

Nice job. I like the removal tool also. Am I reading the Jabsco model number right 9990-1?
I need to get a back up pump for my old Obedorfer pump that's obsolete.

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Jabsco 9990-41, sorry it didn't show up very well in the photo.

Great job! I did the same to my Jabsco pumps years ago and it's been a great improvement. Another trick with the back plates is to reverse a worn one to get more life out of the one you have.



I also had one pump that was difficult to get primed after an impeller change. I called Jabsco and they explained that there is a replaceable wear plate on the back side of the impeller. A very fine pick was needed to grab an edge to remove it. Jabsco sent me a new one gratis and it solved the problem.

Here's my impeller removal tool...

Helen Marie said:

Jabsco 9990-41, sorry it didn't show up very well in the photo.

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Thank You.Ouch that's a pricey one.

Pack Mule said:

Thank You.Ouch that's a pricey one.

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Wish I could have one as cheap as that, only $500 here.
Try a 7420-1001, here they are more like $1200

Speedseal - http://www.speedseal.com/SpeedsealLife/Lifehowitworks.htm

And if you bump the starter with the cover off the impeller will start moving out of the case and is then easy to grab.

The allen head screws can be removed or installed blind.

A huge advantage with some pump locations.

Very little torque is required (the stock slotted screws were brass) to have a watertight seal, so a std allen wrench is all thats needed.

Max Simmons said:

Dave, is there any issue with mixing metals?

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Nope, not in my engine room. Everything is nice and dry. The photos are from my 34DeFever with the Perkins 6-354.
My new boat has a Sherwood raw water pump