3rd year on raw water pickup impella

Seems to pick just fine. Is this taboo?

It's certainly possible. My little outboard impellors go for 7 years or so. But, my E35 sherwood has been known to eat up the impellor in just 50 hours, due to a worn cam and maybe some silt. So, the life has a high dependancy on sand/silt and the internal condition of the pump. Assuming it never runs dry/seacock is not forgotten!

Two big things kill them - Dave got one. the other is sitting idle. The rubber compound loses its flexibility so the vanes don't snap back coming off the cam. Eventually, if not eroded at the edges, the vanes wind up cracking.

the risk is the damage due to overheating if the pump doesn't deliver. That will far exceed the cost of the impeller kits.

You can always pull the pump and inspect the impeller. If the vanes' structure is acceptable and there are no "parts" in the housing, you could deem it serviceable.

Taboo - no.
Borrowed time - yes.

At the very least (especially if it is a single screw) keep a rebulid kit and tools on board.

got a spare and tools onboard. Its not the money but the effort to pull and look.
Its tight access. I should see the overheating and shutdown before damage, yes?

The last ones almost 3 years next month came out so clean and healthy and was in at least 5 years (not in sandy area).

The water pump impellers on my 454 CIDs have been in service since 2002. The boat is in fresh, clean, non-sandy water on the Tennessee River at Pickwick dam. The starboard side is getting in need of changing. I recon this by measuring the temperature of the elbows with the infar red gage. On the starboard engine one is 110 degrees and the other is 130. On the port side both are 110 degrees. These temps are at cruise, which for me is 1400 RPM. I have no steam on either side. I had rather change in the slip. I hate working on the boat in open water with the wind blowing and the waves rocking it.

Chuck Hanson

I like Chuck's plan...it is easier to be tied to the dock than banging against wind and waves at the worse possible time BECAUSE THAT is when it happens.

I had an impeller on a Westerbeke generator go bad after only a few hours with the exact reason unknown. I have used my E35's for 3 years as well but somewhere along the line she must have picked up something as there was a well worn groove in the cover plate that year. My thinking is you gotta inspect them and since they are not an expensive replacement, I'll at least be prepared every season or 2 to do it