Double blisters on every rib

[nyryan2001]

Is how your impeller starts to deteriorate and break apart.

Just under 2yrs, 190hrs, 2 winterizations.

Noticed I was running approx 2-3degs higher than normal while at idle after a run. 169-172 is my normal. I was seeing 175 at idle. At speed it'd drop back down 154-162.

Swapped out the impeller... Double blisters on every rib... So it wasn't getting the full length squeegee effect on each rib inside the pump. If you see your idle temps creep up... This is where it starts.

[4th ski-doo]

Good catch, I need to pull mine because I'm seeing the same on the temp guage. It's about the same amount of hours, little surprised it died already myself.

[Paxdad]

If it came out of a small white box the impeller is a Chinese knock off of the PCM oem part. They are an inferior part.

[d_nodixon]

I've changed several impellers and all had the same wear pattern, no temp issues to report. The wear pattern matches the two oval slots

[NautiqueJeff]

If it came out of a small white box the impeller is a Chinese knock off of the PCM oem part. They are an inferior part.

Most of those from that batch died within ten hours of use or so.

[JoeA]

What's normal operating temp on the XR550? I could swear mine has run 174 all day long since I picked mine up. It sounds like Ryan's runs a little cooler than mine albeit mine is a year newer.

[JoeA]

I think I found my answer. Acording to the PCM owners manual the 409, 450 and 550s run FWC (fresh water cooling ?) 160 degrees. I'll be sure to monitor this today, but could swear I've been running 174 degrees consistently since day one. I'll check the fresh water strainer today.

What's everybody else experiencing in terms of operating temps?

[nyryan2001]

With the new impeller installed yesterday the highest sustained temp at idle was 168-172ish.

As soon as you give it some gas and the RPMs rise, 154-165 range depending on speed and RPM.

[NautiqueJeff]

My 550 always ran hotter than my 450 engines do.

[nukemustang]

Those should line up with the metal piece in the raw water pump housing. I took a pic the other day using my iPhone when mine was disassembled to see in side since it is a v-drive.