I ordered a new magnesium anode for the heat exchanger to go with the new one for the prop shaft. When I removed the old one, there was no anode material left at all. Then I noticed that the heat exchanger tube had a large bulge at each end, like a chipmunk with a mouthful of nuts. So it's either bulging from internal corrosion (doubtful), or was not winterized at some point in the past and froze? Regardless, looks like I'm buying a new heat exchanger! They seem to range from $800+ for OEM down to $350 for aftermarket. Any tips or advice?
Thanks!
Don
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Don Lincoln
"Nancy Lynn"
1993 Catalina MK1.5, Hull 1238
LaSalle, MI (Lake Erie)
Universal M-35AC
I've been looking at the Seakamp or Mr. Cool 3" saltwater versions to replace my 2" heat exchanger, You might also take it to a radiator shop and see if they can repair it. The endcap(s) are slightly domed so it might be normal,
Les & Trish Troyer
Mahalo
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor.
Commodore
The Seakamp was the one I was considering as well. Unfortunately, it's the tube that has bulged and not the end caps.
Don Lincoln
"Nancy Lynn"
1993 Catalina MK1.5, Hull 1238
LaSalle, MI (Lake Erie)
Universal M-35AC
We installed the 3" diameter Seakamp about 6 years ago (an upgrade from the OEM 2" HX). Works fine, although it was a total bear putting it back in the original location, and a few years later relocated it for much easier access. See this thread (and the links to other threads therein):
https://www.catalina36.org/comment/57504#comment-57504
Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY
When we moved our first boat from California to Connecticut, we had no concept of "seasonal" and ended up with the bulges that you mentined due to freezing. The heat exchanger worked fine for another decade. If you don't want to replace, you could take to a radiator shop for cleaning and testing.
BTW, if you suspect a heat echanger is leaking, closely monitor your coolant levels. An unexplaind and slow loss of cooland may signal the beginning of the end to your heat exchanger.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Very helpful info. I might save the oney and wait and see what happens. Nothing has been leaking, so maybe I can keep it as-is for the time being.
Don Lincoln
"Nancy Lynn"
1993 Catalina MK1.5, Hull 1238
LaSalle, MI (Lake Erie)
Universal M-35AC
stupid question for those who have moved their heat exchanger aft.... Did you provide some electrical bonding from the engine to the new location so the Zinc has a path to "ground" ?? The current location is bonded via the mount and clamps holding to the mount. Does the Zinc still work without the bonding??
Thanks
Les
Les & Trish Troyer
Mahalo
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor.
Commodore
[quote=LeslieTroyer]stupid question for those who have moved their heat exchanger aft.... Did you provide some electrical bonding from the engine to the new location so the Zinc has a path to "ground" ?? The current location is bonded via the mount and clamps holding to the mount. Does the Zinc still work without the bonding??[/quote]
Very helpful question, actually. The answer to the first question is "no", and to the second it may be "no" as well.
Reflecting on this, I recall being very surprised at how little erosion I've seen on the anode this season. (Second year since I moved the HX, don't recall what the anode looked like last year).
[quote=Catboat Willy] ...
And yes, the heat exchanger should be grounded to the engine.
Bill[/quote]
Hmm. Maybe I better run a bonding wire. Especially because ...
[quote=newguy]
...BTW, if you suspect a heat echanger is leaking, closely monitor your coolant levels. An unexplained and slow loss of coolant may signal the beginning of the end to your heat exchanger.[/quote]
I've noticed a slow loss of coolant this season. Du-oh.
Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY
[quote=Chachere]
I've noticed a slow loss of coolant this season. Du-oh.
[/quote]
Yup. With a leaky car radiator, since the exchange medium is air, you'll find the loss of coolant on the ground (if you're lucky). With a leaky marine heat exchanger, since the exchange medium is sea water, that coolant goes out the exhaust. Investigate all other possibilities though, especially if you've serviced your cooling system lately and it might just be air being completely burped out. This can sometimes take quite a while.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
I had read somewhere on the site here, to insulate the HE from the engine brackets. Your little pencil anode is for the salt water system
in the HE only, to protect it in its own little ecosystem. Be sure the anode makes good connection with the HE threads.
I might replace the anode 2x a year with never a great deal of loss.
Gary Matthesen
"Holiday"
1987 #50646
Oyster Bay Long Island NY
Don;
Several months ago, I decided to replace my heat exchanger for my M35. I used a LENCO model
LE 302631 which was an exact fit for my old one. Cost was $350.00 and shipping was another $25.00 and arrived within four days. LenCO is in North Amityville, LI, New York tel; 631 842 4049. HINT: Be very careful to measure the correct length of the zinc used in the exchanger as too long a zinc will pierce the heat exchanger tubes. If you are just going to use the heat exchanger you have now and want to know the correct size needed, use a pencil and measure how far it will go in to the heat exchanger and adjust you length accordingly. As you have probably found out, the zinc unscrews from it's cap. We are able to get our zincs at the local hardware store can cut them down to size. I change mine every six months but that's overkill.
And yes, the heat exchanger should be grounded to the engine.
Bill
Bill Dolan 1990 Catalina C-36 MKI - Hull #1041 'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'
Thanks for the info Bill. I will definitely check the Lenco out. As for the zincs, I am opting to use magnesium since I am in fresh water in the great lakes and that is what is typically recommended. Magnesium ones are more difficult to find, and I'm guessing the hardware store wouldn't have them. But it's worth checking! Thanks again!
Don Lincoln
"Nancy Lynn"
1993 Catalina MK1.5, Hull 1238
LaSalle, MI (Lake Erie)
Universal M-35AC
Gary, I think what they were talking about in the forum post was to isolate the heat exchanger from the vibration of the engine.I know that after reading that article I went out and found some thick silicone washers and mounted them between the heat exchanger and the engine block to absorb the vibration+
.
Bill Dolan 1990 Catalina C-36 MKI - Hull #1041 'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'
That makes more sense to me!
Don Lincoln
"Nancy Lynn"
1993 Catalina MK1.5, Hull 1238
LaSalle, MI (Lake Erie)
Universal M-35AC
As I say to my wife, "Damn! I hate when your right!"
Gary Matthesen
"Holiday"
1987 #50646
Oyster Bay Long Island NY
Quick update on this thread. I did end up replacing the exchanger with an equivalent Seakamp. This was a bear of a job as others have mentioned. It took about 4 hours and 2 trips to the auto parts store (first for penetrating oil to loosen the frozen bracket bolts, and the second for a replacement water hose). I'm hoping I don't have to do that one again!
Don Lincoln
"Nancy Lynn"
1993 Catalina MK1.5, Hull 1238
LaSalle, MI (Lake Erie)
Universal M-35AC