36-1 Repower or 3HM35 heat exchanger?
Good day,
In the process of doing some much needed engine upkeep on a 3HM35 and I
found the heat exchanger case has some corrosion around the front seal and
may not reseal or at least not for very long. There is quite a bit of
additional corrosion around the front of the same case. The local yanmar
shop said they looked for a replacement to no avail. Perhaps someone here
knows of a lead?
That said I’m not entirely opposed to dropping a new engine in because the
heat exchanger isn’t the only issue and I don’t even know the serial number
because the ID plate fell off before I became the owner and who knows the
total hours.
My understanding is these boats were originally fitted with the 3QM30 but
at some point a 3HM35 with 2 bladed folding prop was installed in mine. My
question is if a 3YM30AE would be a sufficient replacement. The local shop
points out the higher rpm of the 3YM and believes it would be underpowered
compared to the current 3HM and is suggesting a 3JH40.
I’m interested to hear any thoughts or experiences you might have. Thanks
in advance!
Jacob Fuerst
303-520-4669
1978 C&C 36
Ventura, CA
Keep and eye on ebay. You can find lots of used parts for the 3HM.
A machinist will probably have ideas about how to get yours to seal. After exhausting professional options, I'd try employing JB Weld epoxy putty. You could manufacturer a flat plate to bolt or press in place of the end bell. Use mold release so the plate isn't permanent. By using the plate, you create a flat face against which the JB Weld will form. Use a dremel to clean up the details once it is cured. Repeat for the end bell. Now with 2 flat surfaces you shouldn't have trouble getting a seal.
Josh Muckley
S/V Sea Hawk
1989 C&C 37+
Yanmar 3HM35F
Solomons, MD
Apr 10, 2024 08:36:04 jacob fuerst via CnC-List cnc-list@cnc-list.com:
Good day,
In the process of doing some much needed engine upkeep on a 3HM35 and I found the heat exchanger case has some corrosion around the front seal and may not reseal or at least not for very long. There is quite a bit of additional corrosion around the front of the same case. The local yanmar shop said they looked for a replacement to no avail. Perhaps someone here knows of a lead?
That said I’m not entirely opposed to dropping a new engine in because the heat exchanger isn’t the only issue and I don’t even know the serial number because the ID plate fell off before I became the owner and who knows the total hours.
My understanding is these boats were originally fitted with the 3QM30 but at some point a 3HM35 with 2 bladed folding prop was installed in mine. My question is if a 3YM30AE would be a sufficient replacement. The local shop points out the higher rpm of the 3YM and believes it would be underpowered compared to the current 3HM and is suggesting a 3JH40.
I’m interested to hear any thoughts or experiences you might have. Thanks in advance!
Jacob Fuerst
303-520-4669
1978 C&C 36
Ventura, CA
Hi Jacob
To second what Josh said. I repaired a SB8 Yanmar cooling system with JB
weld 6 or 7 years ago. It is still holding with no leaks.
Douglas Mountjoy
1988 C&C LF 39
Mexico at large
1984 Sabre 34
Port Orchard, WA
On Wed, Apr 10, 2024, 05:35 jacob fuerst via CnC-List cnc-list@cnc-list.com
wrote:
Good day,
In the process of doing some much needed engine upkeep on a 3HM35 and I
found the heat exchanger case has some corrosion around the front seal and
may not reseal or at least not for very long. There is quite a bit of
additional corrosion around the front of the same case. The local yanmar
shop said they looked for a replacement to no avail. Perhaps someone here
knows of a lead?
That said I’m not entirely opposed to dropping a new engine in because the
heat exchanger isn’t the only issue and I don’t even know the serial number
because the ID plate fell off before I became the owner and who knows the
total hours.
My understanding is these boats were originally fitted with the 3QM30 but
at some point a 3HM35 with 2 bladed folding prop was installed in mine. My
question is if a 3YM30AE would be a sufficient replacement. The local shop
points out the higher rpm of the 3YM and believes it would be underpowered
compared to the current 3HM and is suggesting a 3JH40.
I’m interested to hear any thoughts or experiences you might have. Thanks
in advance!
Jacob Fuerst
303-520-4669
1978 C&C 36
Ventura, CA
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Thanks for your help.
Stu
Jacob,
Like Josh suggested, a good machine shop can probably help. Failing that,
I'd take the exchanger to a good radiator shop.
I had corrosion and leakage on the sealing surface of a side plate of the
Atomic 4 that was in Touche' when I bought it. Repaired it with JB Weld
and a flat file. Sealed up great and didn't leak for years until I
repowered it.
Is this it?
https://www.dam-marine.com/gb/home/32570-yanmar-3hm35-cooling-fresh-water-cooler-75b8dbdd.html
BTW, there's a complete 3HM35F on eBay for $5000.
--
Dennis C.
Touche' 35-1 #83
Mandeville, LA
On Wed, Apr 10, 2024 at 7:35 AM jacob fuerst via CnC-List <
cnc-list@cnc-list.com> wrote:
Good day,
In the process of doing some much needed engine upkeep on a 3HM35 and I
found the heat exchanger case has some corrosion around the front seal and
may not reseal or at least not for very long. There is quite a bit of
additional corrosion around the front of the same case. The local yanmar
shop said they looked for a replacement to no avail. Perhaps someone here
knows of a lead?
That said I’m not entirely opposed to dropping a new engine in because the
heat exchanger isn’t the only issue and I don’t even know the serial number
because the ID plate fell off before I became the owner and who knows the
total hours.
My understanding is these boats were originally fitted with the 3QM30 but
at some point a 3HM35 with 2 bladed folding prop was installed in mine. My
question is if a 3YM30AE would be a sufficient replacement. The local shop
points out the higher rpm of the 3YM and believes it would be underpowered
compared to the current 3HM and is suggesting a 3JH40.
I’m interested to hear any thoughts or experiences you might have. Thanks
in advance!
Jacob Fuerst
303-520-4669
1978 C&C 36
Ventura, CA