air con anodes?

I found the base tray full of sea water when I did normal checks, though it may have been weeping for a while without me noticing. The engineer changed some other parts in the raw water loop at the same time, including the pump and any metal connecting tubes, so you may need to replace these as well.
 
I've had a look at mine.
Although mine is the 17.5 KVA set, the heat exchanger is on the right.

Do you know how easy it is to change it.
I've found the manuals and it looks like there are two hoses at the back that will need to be removed.
It may be difficult to get at them - see this diag - hoses 10 and 11

Mine is starting to show some external corrosion at the point where hose 19 attaches to the heat exchanger.
Not leaking - yet!
Is this where they corrode?
BTW - the anode has been changed regularly.

HeatExchanger_Small_zpsjikch6du.jpg




EDIT

I've just taken the top panel off and it may be possible to reach the jubilee clips at the bottom of those two rear hoses.
Thats all assuming that after removing the jubilee clips, that the hoses will come off.
Maybe thats why Nick's engineer changed the hoses as well!!

I think I will get a new heat exchanger anyway - SWMBO is flying back and forth so, if I can find stock I will get one out here anyway - just in case.
Thanks for the advice.

BTW - who are ARE - I've been using Seapower Marine Parts for my Onan spares.
 
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Hi Hurricane
ARE is Anthony E, poster on here, very knowledgeable and helpful on all Cummins Onan things. He works for them in his day job

I'd forgotten where is it on the 17.5 but your picture shows it well. Mine (on the 23kva) is mounted vertically at front of genset - much easier

If you can get your arms in I would just devote the 3 hours to changing it. Screws #4 might be hard to reach. They just do fail at 8 years, and as ever that will happen at an inconvenient time with a hot engine room. The corrosion on mine was where the end cap (#30) fitted on, and might have been fixable by getting new end caps and cleaning up/repainting the heat exchanger body, but it seemed better to fit all-new so I did

Incidentally, if you lose an impeller blade it is usually to be found just inside the heat exchanger end cap having travelled along hose 19. I always look in there when I change an impeller, unless the impeller has all its blades
 
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I agree with this. I got 9 years from my 11 MDKAZ heat exch. Took the old one home, descaled it, new end caps paint & is now my spare.

Slight drift, how long do the injection mixer elbows last?
 
Hi Hurricane
ARE is Anthony E, poster on here, very knowledgeable and helpful on all Cummins Onan things. He works for them in his day job

I'd forgotten where is it on the 17.5 but your picture shows it well. Mine (on the 23kva) is mounted vertically at front of genset - much easier

If you can get your arms in I would just devote the 3 hours to changing it. Screws #4 might be hard to reach. They just do fail at 8 years, and as ever that will happen at an inconvenient time with a hot engine room. The corrosion on mine was where the end cap (#30) fitted on, and might have been fixable by getting new end caps and cleaning up/repainting the heat exchanger body, but it seemed better to fit all-new so I did

Incidentally, if you lose an impeller blade it is usually to be found just inside the heat exchanger end cap having travelled along hose 19. I always look in there when I change an impeller, unless the impeller has all its blades

Thanks
Actually, there seems to be a bit of a discrepancy as to which part is the one for my genset.
So, I've sent him a PM
Sounds like he might be the guy to give me the correct answer.
 
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