Onan 5MDKBH Generator

[Patrick]

Hello All,

Can anyone tell me if this 2006 5KW generator has a replaceable zinc?

Can’t find any obvious sign of one.

Thanks.

Topic

[Patrick]

That is a slick set up. Well done.

Dan wrote:

Patrick wrote:

Did you plumb a permanent adapter to hook a garden hose too?

Through a tee on the intake side of the raw water strainer (blue valve in picture attached) that is connected to a distribution manifold that both engines, air con, live well pumps, wash down pumps and the generator are fed through a water hookup on deck, I can flush all with the garden hose or the onboard freshwater supply with one hookup.

[Rob Schepis]

Very thorough Dan. Not sure what climate your boat lives in but a system like yours is also highly appreciated when it comes time to run the non-tox antifreeze through all raw water components.

[Dan]

Patrick wrote:

Did you plumb a permanent adapter to hook a garden hose too?

Through a tee on the intake side of the raw water strainer (blue valve in picture attached) that is connected to a distribution manifold that both engines, air con, live well pumps, wash down pumps and the generator are fed through a water hookup on deck, I can flush all with the garden hose or the onboard freshwater supply with one hookup.

[Patrick]

Did you plumb a permanent adapter to hook a garden hose too?

I guess you could just “T” into the raw water side after the seacock and close the seacock to flush?

[Patrick]

Thanks for the replies. I have never had the exchanger off and I’m sure the previous owner didn’t service it.

Being 13 yrs old, I think it’s time to pull it. Generator has 290 hours on it.

I replaced the impeller when I bought the bought a few years ago.

Seems really strange to build this model generator without a replaceable anode? I’ll post some pics when I get it removed and apart.

[Dan]

I have this generator, theres nothing in the manual about zincs and I’ve looked hard for them,I installed freshwater flush from new.

If you have ever had a water pump impeller failure I can almost assure you the broken pieces are almost guaranteed to be lodged in the sharp elbow on the outlet side of the pump, if not there they will be sitting in the inlet side of the HX, due to how the HX is installed you need a small telescopic mirror to find them to fish them out.

Hope this helps.

2 users thanked author for this post.

Patrick, Rob Schepis

[Rob Schepis]

A zinc would be on the body of the heat exchanger (not on an end cap) and may look like a drain plug, especially if it’s painted over. But there is a chance it does not exist as I have heard of some Onan’s without a zinc. Best bet is to pull the heat-exchanger for bench service. What is the known heat exchanger service history?

[David R Flamer]

They are usually on the heat exchanger. Take some good pictures of it and post them, especially the bottom of it. I am sure there is one there and someone can guide you to it.

[Patrick]

The manual says there is no replaceable zinc.

How does the heat exchanger not corrode without a zinc?

[Author]

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