Anyone have experience with these companies and their Fresh Water Conversion Kits?

Smokin_Joe

Recruit
Joined
Oct 3, 2013
Messages
5
I would like to install a full system fresh water kit.
A local Mercruiser dealer told me that they didn't offer a fresh water conversion prior to approximately 2000ish. I have found a few aftermarket systems that could work but since I know nothing I felt I should ask for your opinion.
I am looking for the best quality to fight corrosion, ease of install, reliability etc
(I have some serious manual dexterity issues and fabrication should be at a minimum...plug and play please..lol)
Some of the web sites are very professional while others are plain.
The boat is a 1985 20' Century Cuddy
Drive Unit serial # A481138
Transom serial # A521520
The maintenance manual says it is a Model 230MR
Here is what I have found for kits and suppliers

https://www.perfprotech.com/mercruis...product/242881

https://www.mrcool.us/mfh-5399-stand...-manifold.html

the following link won't work and I think it is caused by the forum...
https://www.**************/Full-Fresh...-86-95-SK-4821


Links in the following didn't work for my application but I included site for your opinion...

https://www.cpperformance.com/t-mari...g-systems.aspx

I am looking for approvals, warnings ...whatever would help me decide.
Thank You for your time.
Joe
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
18,143
I got a 'Closed Cooling' kit through Michigan Motorz . . . it was made by San Juan Engineering (SJE). The SK-4821 kit that you tried to post a link to is a SeaKamp kit. IMO probably the better of the kits.

"Fabrication" not so much , but dis-assembly and re-assembly of the engine's cooling system is fairly extensive. Plan on it taking a whole day or longer. The instructions on my SJE kit was fairly vague, so I had to figure some stuff out myself.

I installed a 'Full' closed cooling system on my twin engines (so 2 kits). I did not like how the thermostat flow was designed, because it restricted flow through the exhaust manifolds too much until the engine rose to temperature, then there would be a rush of super hot coolant coming from the exhaust manifolds which caused the temperature to spike. I'm sure it would settle down after a while, but I did not like it. Soooo, I did a little bit of fabrication on the thermostat to resolve the issues.

You are installing closed cooling on an older engine? :noidea: sounds like it. If the engine has been in fresh water only then maybe OK, if any salt water than not so good . . . too much rust scale in the engine . . . the heat exchanger will get clogged
 
Last edited:

Smokin_Joe

Recruit
Joined
Oct 3, 2013
Messages
5
I got a 'Closed Cooling' kit through Michigan Motorz . . . it was made by San Juan Engineering (SJE). The SK-4821 kit that you tried to post a link to is a SeaKamp kit. IMO probably the better of the kits.

"Fabrication" not so much , but dis-assembly and re-assembly of the engine's cooling system is fairly extensive. Plan on it taking a whole day or longer. The instructions on my SJE kit was fairly vague, so I had to figure some stuff out myself.

I installed a 'Full' closed cooling system on my twin engines (so 2 kits). I did not like how the thermostat flow was designed, because it restricted flow through the exhaust manifolds too much until the engine rose to temperature, then there would be a rush of super hot coolant coming from the exhaust manifolds which caused the temperature to spike. I'm sure it would settle down after a while, but I did not like it. Soooo, I did a little bit of fabrication on the thermostat to resolve the issues.

You are installing closed cooling on an older engine? :noidea: sounds like it. If the engine has been in fresh water only then maybe OK, if any salt water than not so good . . . too much rust scale in the engine . . . the heat exchanger will get clogged

Someone said the San Juan Engineering was bought by Orca Marine
http://www.orcamarine.com/index.html
They are quality custom manufacturers located in Bellingham just south of our Canada US border.
I just put in a request for info on kit 400321.
That is good info concerning the thermostat I will watch for that and when I get a response from Orca I will try and ask them if they have corrected it.
I wonder if an antifreeze filter, like used on a M11 Cummins, would help with keeping the closed system clean...hmmm
Thanks tpenfield
PS...Why did you feel "SeaKamp kit. IMO probably the better of the kits."
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,261
make sure you clean out the crud in the block. if you are a fresh-water only motor for now, rust will be at a minimum.

however the fact your motor is 36 years old, I would not waste time or money on a HX until you repower.
 
Top