Heat exchanger and RTV

[kiwikol]

Has anyone experienced using RTV, when re-assembling a heat exchanger, at the interface of the main body and the end caps (where there is an ‘O’ ring) ? In my case with a Yanmar and no anodes, it would seem a good idea in order to protect the aluminium main body from contact with salt water where there is also a dissimilar metal situation, the end caps and core being (?)cupro-nickel. I have experienced corrosion in this area due to an incorrect assembly from manufacture – but that’s another story for a book which I’m sure will become a best seller in due course (much to the detriment of Yanmar!).

 

[Kawasaki]

Hmm, not a fan of RTV etc in this situation.
I think end caps should be inspected regularly.
O rings replaced when needed.
When needed depends on the situation regarding how bad electrolysis ((however it is spelt) is in Your area.
Tiss rampant in our Marina.
I had a Ford Mermaid in My previous boat, no protection on the engine.
The end caps on the heat exchanger and the header tank soon rotted.
It became a once a season Gig to remove and check.
The best solution was to replace the o rings regularly and to re assemble using vaseline to help stem the rot.
My current boat has a Volvo unit, with engine and gearbox anodes fitted.
Still requires attention in a similar vein but so far it's about a 2 year interval before the rot starts to set in.
I must point out that the Marina has a real prob with this Lark.
I,ve had noticeably, less cathodic snags whilst out of the Marina on a swinging mooring.
Some say the problem is worse whilst "hooked up" to shore power too.

 

[pbeard]

I wouldn't have a problem using RTV in that situation, it can be seperated with a scalpel type tool; but use the red type which withstands high temperatures.