How tight should an impeller be

[spharis]

Still fresh to inboards, so needing some explanation.

I pulled my impeller with the intention of going to a Globe model 75 according to their guide)
Globe specs 2 1/4" X 1 1/4" 5/8 12 blades

The one that was in it and chewed up was a Jabsco 1210-0001
Jabsco 2 1/4" X 1 1/4" 12 blades

The Jabsco was fairly crammed in there. I don't know if that's normal, or if that's whay it was chewed. It really didn't seem to be the proper size. There was minimal clearance around the impeller and the blades were really flexed. How do you measure for the proper size impeller? This Jabsco was supposed to be new, so it should have less than 15hours, and it has already loast 3-5 blade sections.

[kko]

they fit tight. you need to find out why it chewed it up!!!!!!!!!!!!!!!!!!! do you have a sea strainer? if not pull the hose leading into tranny cooler and see if it is clogged. with only 15hrs on it something happend that caused it fail.

[spharis]

Well, I am swapping the water pump before next season, so inspecting all the cooling hoses will be on the list too. For all I really know, it's old. I bought the boat secondhand.

[dogbert]

Still fresh to inboards, so needing some explanation.

I pulled my impeller with the intention of going to a Globe model 2000 (according to their guide)
Globe specs are 2.5"X2" 12 blades

The one that was in it and chewed up was a Jabsco 1210-0001
Jabsco 2 1/4" X 1 1/4" 12 blades

The Jabsco was fairly crammed in there. I don't know if that's normal, or if that's whay it was chewed. It really didn't seem to be the proper size. There was minimal clearance around the impeller and the blades were really flexed. How do you measure for the proper size impeller? This Jabsco was supposed to be new, so it should have less than 15hours, and it has already loast 3-5 blade sections.

They fit tight...most folks recommend using dish soap to get it into the housing. They're also made of rubber which means that they get brittle so even with only 15 hours on it, if it's more than 2 years old, you were probably due. Also, if you suck anything up into the impeller, you'll lose a few blades.

I replace mine every 2 years whether it needs it or not. Even with that, I've managed to suck up debris that trashed it once. It just happens.

[spharis]

Yeah I figure it was just time....it is brittle. Some of the blades are cracking near the main hub. Using globes guide, I found a replacement should be model 75. 2 1/4" X 1 1/4" X 5/8" 12blades.

[yllw20]

It should be tight. I change mine every year and carry a spare on the lake.
If it is brittle and cracking it is old. No matter what your hours are you have to think about this is a rubber piece which becomes wet and dry and goes thru a range of heat. You would want to check your tubes to make sure there is no debris in them from the missing blades.

[spharis]

I just ordered a new water pump, so all the hoses are getting inspected inside and out too. I need to check the hose springs near the pump anyway.

[spharis]

Old water pump was S H O T! It was hard to see because of the pulley, but it looks like it should have been changed about 2 seasons ago. Inside of the hoses and rest of the plumbing was all good, except for the collapse spring. I'm off to autozone for a metal fuel filter, and some new water pump and pulley bolts after work. I pulled the pump off on my lunch break. It's nice working about 5 minutes from my house. I just have to make sure I don't get my golf shirts and shiny shoes dirty

On another note, I got some catalogs in the box with my new water pump, and I was looking at some shiny new powder coated exhaust manifolds......nice......

[Domsz06]

it's a tight fit, and mine gets replace every year!

[spharis]

I bought a globe. It's a hair smaller than the Jabsco I pulled out, but just a hair. According to the charts at Jabsco and Globe, it should be the same size. BTW I have charts for all pumps and impellers. I'm starting to get a library of sorts going since factory manuals are a nono.

[Domsz06]

that library will be very nice, and quite handy as well!