Weep Hole Leaking After Impeller Replacement

[Bob Moriarty]

Replaced the 8-year-old impeller on my MMI 502 flange pump with a new impeller from Moyer. With the new impeller in place and the engine running, there was quite a bit of leakage through the upper and lower weep holes. I put the old impeller back in and the leakage stopped.

The older impeller seems a tiny bit thicker than the new one. It also has a 8(?)-sided metal ring embedded in the rubber. In the replacement, the ring is circular.

Do the impellers expand over time?

I've searched the forum and only found this possible clue:
"Don't forget about the impeller thickness discrepancy that emerges from time to time."

Thanks in advance for any ideas.

Bob Moriarty
Ox 33-1
Jax, FL

[Bob Moriarty]

After posting this, some relevant similar threads appeared at the bottom.

I've learned:
1) Impellers can expand over time.
2) Expanded impellers can wear away and increase the size of the cavity/chamber(?) that contains them.
3) Soak the new impeller in Marvel Mystery Oil. That stuff has so many uses. I brush my teeth with it.
4) Measure the new impeller. It should have a thickness of 7/8"
5) Try running for awhile with the new impeller and the leakage. Maybe the impeller will expand and the leakage through the weep holes will stop.

Bob Moriarty
Ox 33-1
Jax, FL

[romantic comedy]

As far as I know, the weep holes are for water to leak out when the seal fails. The impeller should have no effect on this.