Im in a bit of a pickle with heat exchanger

[Catboat Willy]

If you feel you might need a new heat exchanger:
Contact Lenco Inc. North Amityville, LI, NY on your way home to R.I.
Tel ; 631-842-4049.
They will custom build you exactly what you need but it might be a good idea to take the old one and/or send it to them or drop it off.
We've done that for obsolete engines.

[CarlF]

I expect St. Augustine is full of small shops that could fix it. And even more 45 minutes up the road in Jacksonville. A lot of the skilled workers who used to be in RI are now in the south. Northrop Grumman has a big plant at the St. Augustine airport that upgrades F5 fighters.

Just ask around when you get there. Likely to be cheaper than RI too.

[JPA Cate]

To me, the problem with dealing with heat exchangers is that they can be destroyed.

I do think the OP would be better off with a new one. Then he can rebuild the old one and carry a spare. But, he's the only one who can decide if a patch could get him beyond Cape Hatteras and into port. Bear in mind that the weather is getting colder and blowier. Maybe he'd feel safer with a new one.

Ann

[Minggat]

[QUOTE=phorvati;3024393]Yes it is copper nickle or whatever its called. .

QUOTE]

Cupronickel or copper-nickel (CuNi)

[gcrothers]

You could use an industrial strength epoxy like Belzona 1111 or the higher temp version 1511. It's super expensive stuff but I've seen it used in pretty extreme uses.

[Draughty]

Hi,
Engine reconditioning shops are a good bet for high class alum welding.

Rgds all.

[sailah]

I repaired my Westerbeke heat exchanger using silver solder and a torch set. It's not a hard job, mine had cracked at the joint as well as a couple really small snakebites where PO had cranked on hose clamps.

Been fine for years now. Trick is CLEAN, flux, solder.

[phorvati]

Originally Posted by sailah

I repaired my Westerbeke heat exchanger using silver solder and a torch set. It's not a hard job, mine had cracked at the joint as well as a couple really small snakebites where PO had cranked on hose clamps.

Been fine for years now. Trick is CLEAN, flux, solder.

That looks very good. I left my MAP gas tools in RI. I had just finished building the fridge so i have exactly that. My only thing is that wall looks so thin. I need entirely new endcap, so i think. But it needs to be solder style as there is no bolt and gasket on that end. I wonder if TSA lets you take solder and flux on a plane. I'll have to buy a bottle of MAP gas.

[billknny]

[QUOTE=Minggat;3024951]

Originally Posted by phorvati

Yes it is copper nickle or whatever its called. .

QUOTE]

Cupronickel or copper-nickel (CuNi)

Or “Monel”.

[a64pilot]

Originally Posted by phorvati

That looks very good. I left my MAP gas tools in RI. I had just finished building the fridge so i have exactly that. My only thing is that wall looks so thin. I need entirely new endcap, so i think. But it needs to be solder style as there is no bolt and gasket on that end. I wonder if TSA lets you take solder and flux on a plane. I'll have to buy a bottle of MAP gas.

Soldier and flux is fine, just remember it’s silver solder which is much more expensive and doesn’t come in rolls, but like welding rods.
I’m sure you know about silver solder cause you said Mapp gas and not propane, I’ve used Mapp before to silver solder on a propane torch head, seemed to work fine
Due to traceability I have carried mild steel TIG welding rods in my carry on before going to fix a fuselage, I just let it wrap the sides of my luggage and never had a question, I guess it looked like the frame or something .
Cupronickel ought to solder beautifully.

[phorvati]

Silver solder does come in rolls

[a64pilot]

Originally Posted by phorvati

Silver solder does come in rolls

Your correct, I looked into this as I’ve never used silver solder that was rolled.
I learned some interesting things, first the good stuff isn’t sliver solder, but silver brazing rod, it seems that If the melting point is above 840f then its brazing, not soldering.
I used if memory serves above 50% silver brazing rod and its over $25 a Troy ounce, but for HVAC which this ought to be similar it seems 15% is good.
https://www.hvacrschool.com/5-vs-15-...r-brazing-rod/

[phorvati]

Back in 07 I built my first fridge(thin plate) using this.
https://www.harrisproductsgroup.com/...y-brite-8.aspx
I used it last summer to build 110V AC refrigeration system. I have plenty of it and i like it. No need to go to brazing temperatures.

[phorvati]

So Folks at Myrtle Beach Yacht Club were very generous and they droped the heat exchanger to a near by welding shop for me. And I managed to talk to the shop today and get an answer.
He said the end cap is welded and it should have been removable type with screw and gasket so that you can clean and inspect the tubes. He also said that welded end cap is paper thin and it is near catastrophic failure. Few tubes are also clogged and need to be boiled off.

So that brings me to a sail magazine article https://www.sailmagazine.com/cruisin...day-that-wasnt that PO wrote where he had end cap blow open on the heat exchanger on his way to St. Martin. I believe this is the same heat exchanger and the welded end cap was a fix down in St. Martin.
So i have to remotely spec out and send new heat exchanger and hoses to the Yacht Club before i get there so i can get that installed.

[Ya Ubetcha]

The commercial marine industry uses lots of heat ex-changers that need repair. Find a reputable marine heat ex-changer shop, they will do it correctly.


If you fix it yourself, I would be sure you use compatible metals. If done incorrectly, two different metals in an electrolyte creates corrosion issues not only in the heat ex-changer but also any metals touching the electrolyte.



Also, there should be zincs in the system that may not have been maintained.