SailNet Community - Reply to Topic
Thread: Thermostat for Atomic IV Reply to Thread
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

  Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below

  Topic Review (Newest First)
07-07-2010 07:06 AM
SEMIJim Moyer Marine sells retrofit kits that retrofit the A4's thermostat housing to accept a current-production thermostat.

07-06-2010 10:50 PM
maa1994 Jim,
I know this was a while back, but may I ask what your final solution was on the replacement of your thermostat. I have a 140 that appears to need replacing and is opening at about the 190+ mark. Funny thing is, I bought another Merc 140 and tested it on the stove only to find it responding in the same way.
Any help from anyone would be greatly appreciated.
Best, Miguel
07-31-2005 01:34 PM
Thermostat for Atomic IV

That is correct, I forgot about salt water cooling - though 160 is, according to the A4 manual, the top temp for normal running. Moyer feels that boats should be converted to a self contained cooling system so the engine can run hotte
07-29-2005 05:47 PM
Thermostat for Atomic IV

But running a raw saltwater cooled engine at temps above 140F makes buildup in the cooling passages faster. High temps are for fwc.
07-29-2005 02:55 PM
Thermostat for Atomic IV

Moyer does say that running the A4 at 180 is a good thing and that running it at 160 is not really good for it as the cooler temperature encourages carbon buildup.
07-19-2005 02:19 AM
Thermostat for Atomic IV

Irwin, Yeah i put it in hot water and it''s not opening until a little over 180. it also doesn''t open completely. however it is also becoming apparent that i''ve got some constriction in the cooling system. either in the raw water or fresh water. rust or maybe an old impeller. the raw water intake is fine and the screen is clean. The engine doesn''t overheat at 1500 rpm but will start to overheat at 2000. Jim
07-12-2005 07:18 PM
Thermostat for Atomic IV

I am unaware of an alternative for the atomic 4 thermostat. I think you are stuck. Moyer Marine is a fair place to do business with. Just be sure your old thermostat is the problem. Have you put it in a pot of heated water, with a thermometer, and watched what it did as it approached 140 and 160?
07-12-2005 03:23 PM
Thermostat for Atomic IV

I just saw a price of $100 for a thermostat for my atomic IV (moyer marine) there''s gotta be a better solution! is there an automotive themostat that would work. What''s so special about this particular themostat. I''d love to hear from anyone with any experience. Jim

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

For the best viewing experience please update your browser to Google Chrome