Bowman Heat Exchanger allowing Raw water in

[bobbanks]

1977 Endeavour 37 with Perkins 4108.
I have a Bowman Heat exchanger with 2 rubber boots on each side.
I am getting raw sea water into the coolant side of the Heat exchanger. I can only guess that it must be coming from either rubber boot not sealing on the HE tubestack or from the tubestack itself. Two years ago I took out the Heat exchanger and I inspected it and it was very clean. We pressure tested it in a bucket of water and it held pressure and we saw no air bubbles. My Bowman HE end caps are new, in great condition and double strapped on. I am not sure if they are the problem or maybe my exhaust is clogged (don't think so as i get a decent amount of water exiting the boat) The water may be seeping around the boots but I have new boots and make them tight. I had the problem 2 years ago and it went away but now its back.

I would consider buying a new used tubestack but looking for advice.



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[tkeithlu]

Does your cooling system hold pressure? That seems to me the first question to answer before disassembly. Beg, borrow, or purchase a radiator cap pressure tester. If the system does not hold pressure, then drain it and pressurize it, listening for bubbles or hissing into the raw water side. With a little luck, you'll find the point these two circuits are getting together.

Good luck with it.

[Engine man]

I have all the parts you show in the picture, below. Let me know what parts you may need. Joe

Originally Posted by bobbanks

1977 Endeavour 37 with Perkins 4108.
I have a Bowman Heat exchanger with 2 rubber boots on each side.
I am getting raw sea water into the coolant side of the Heat exchanger. I can only guess that it must be coming from either rubber boot not sealing on the HE tubestack or from the tubestack itself. Two years ago I took out the Heat exchanger and I inspected it and it was very clean. We pressure tested it in a bucket of water and it held pressure and we saw no air bubbles. My Bowman HE end caps are new, in great condition and double strapped on. I am not sure if they are the problem or maybe my exhaust is clogged (don't think so as i get a decent amount of water exiting the boat) The water may be seeping around the boots but I have new boots and make them tight. I had the problem 2 years ago and it went away but now its back.

I would consider buying a new used tubestack but looking for advice. Attachment 257649

Attachment 257651

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