It's just a "Bravo 3" impeller. Buy three of them - replace the impellers in both engines and keep a spare onboard. Make sure you extract all the pieces of broken blades.

 

These are inboards. Same impeller?

 

Yes, same impeller as the Bravo III is used on the 7.4L/454.
(The bravo III has no pump in the outdrive)
It’ll come with the plastic housing, rubber impeller, stainless wear plate, 2 other seals and the bolts $100ish OEM or $75ish Serria or similar.
I’ve had good results using both.

Removing the whole pump on the bracket to install the new kit is often easier.

 

Oh, yeah - I should've explained that the "B3" description is not only confusing for inboard owners, but it's industry-wide, not just a particular brand.

I keep a spare housing, but I haven't had to replace one. I sold one to a neighbor on a Friday afternoon because his cracked when he over-torqued the bolts. Otherwise if you keep sand out of the system they seem to last fairly long.

The wear plate is reversible, so you can re-use those too. That can allow you to sometimes buy just the impeller kit.

 

Get yer bottle of whiskey ready. The pumps on your 340 are in a wickedly horrible location. You will not likely enjoy this project. It's going to make you want an older 400. ha

 

Actually, I did the starboard once a long time ago. Attempted the port and half way thru I said "fukkit" and made the phone call. Could they have put them in a worse spot, like under the tranny?!

 

Found the kit on Amazon. Thanks all.

 

Came today. Under$60 from "ReplacementKits.com.
Looks perfect. Has wear plate, housing, impeller and bolts.

 

I went down today and figured I'd start the project. First bolt on the bracket (lower one) was tight, but gave a bit then seemed to move a little better. After a couple pulls on the (3/8") ratchet it came out and fell in the bilge. I think it broke! If it did, it had to have been weak to begin with for a 3/8" ratchet to snap it. I have to bring a magnet down now and try to fish it out to confirm. I didn't get to the upper bolt as I didn't have a 5/8" open end on the boat. To use a socket I'd have to pull a coolant hose, which I'm trying to avoid. Updates to follow.

 

FWIW when I had the impellers changed on my 99 340 they did pull the coolant hose (both sides I believe). It didn't sound optional when I had it done but it wouldn't surprise me if they were just trying to make some extra money.

Good luck! I hope your bolt is not broken. That would be a tough spot to work the remaining piece out...

 

I think I've finally gotten mine down to a science. I should've timed the last change, but I have it under the 40 minute mark, not including prep. I apply lube to the new impeller and press it into the spare housing and set it aside ahead of time. (plumbers grease when I'm really prepared, dish soap when I'm not) Aside from being able to do this before ever opening the hatch, I've found that it can make the new impeller more cooperative when time comes to mount it and fully-compress the blades.

I no longer try to remove the hoses during disassembly. I've fought that fight in the past and have decided it's not worth it. Keeping the hoses in place makes a few bolts more difficult to get at, but the engine mount conspires with the hoses to make it easier IMO to fight the bolts. I have a set of "stubby" wrenches that help, not to mention that the 400DA has a lot of room around the engines...

Once the housing is free, then I remove the hoses. During re-assembly, the forces of stubborn rubber hose and annoying engine mount almost make the hoses pop back on by themselves.

I've never done this on a 340 though, so this might be useless information...

 

OK, now it's getting real cold, so I think I will tackle this in the spring. I did pull the hoses to drain the manifolds so I don't have to worry about them. I don't care if the pump body cracks, as I have a new one. Everything else, I think, is good.