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  Topic Review (Newest First)
09-23-2013 10:10 PM
Re: atomic 4 cooling system

I try to do it once a year (more if I can manage it).
09-23-2013 08:42 PM
Re: atomic 4 cooling system

Would it be prudent to run this vinegar cleaning periodically, as routine maintenance?
09-12-2013 04:21 PM
Re: atomic 4 cooling system

You're running too hot and getting steam out exhaust - not enough water getting through your system. Be careful with acid - as above, well rusted engines can be finished by cleaning out what's left. Follow the water path. Is water getting to the pump? Close seacock, disconnect @ pump, briefly open seacock with hose below waterline - if water flows, move to thermostat. Take it off and disconnect coil. Have someone turn engine over and watch for water bubbling through thermostat - if flow is there, your problem is manifold or muffler. Next, take hose off back of manifold and turn engine over again and check for flow. Only place left is water lift muffler. My overheating with your same symptoms has usually been weeds sucked completely into inlet and jammed solid at an elbow before water filter, before pump. Hint: did overheat/steam gradually occur or come on quickly? Gradual is a deteriorating system; quick is usually specific point blockage. These are all easy/cheap checks before you start taking big pieces apart.
07-11-2013 08:49 PM
Re: atomic 4 cooling system

A little water vapor may not be an issue with raw-water cooled engines. The water is heated up more than with a fresh-water cooled engine and what you describe is common, especially in cooler waters.
07-09-2013 07:06 PM
Re: atomic 4 cooling system

I'm on my way to the boat now. I'm going to try a compression test and also check for a leaky exhaust manifold. I was told if I unhook the manifold I can blow in one side and put my thumb on the other. I will then be able to find out whether or not it is leaking. I'll keep you posted
07-09-2013 07:02 PM
Re: atomic 4 cooling system

Could have a leaking manifold gasket, thereby allowing cooling water to leech into the manifold. Or, it could be a leaking head gasket, or possibly a cracked head, which could be the result of overheating.

The engine should run at about 145 degrees, and hold about 40 pounds of oil pressure. A compression check will tell you if you have a leaking head gasket, and possibly a cracked head, but it will not tell you anything about the manifold.

Kinda hard for me to diagnose from here, but the folks on the Moyer Marine Forum may be able to shed more light on the subject.

Good Luck,

07-09-2013 12:48 PM
Re: atomic 4 cooling system

Atomic 4s and their cooling problems. It's a bummer when the wet/exhaust line starts to melt. I've always got my eye on the temp gauge. Usually runs great, but occasionally overheats. After cleaning my block I run a steady 160 degrees.
07-09-2013 11:46 AM
Re: atomic 4 cooling system

Thanks Gary!
I'm pretty sure its steam. It doesn't last more than 5-10 ft before dissipating. I did an oil change and ran the boat for 10 hrs give or take and the oil is full and clean. I'm thinking about trying a vinegar flush. I think two acid flushes might be too aggressive. Is it possible I have a cracked manifold or head? Is there an easy way to check? How about a compression test? Thanks!!
07-09-2013 11:04 AM
Re: atomic 4 cooling system

If it is white smoke, that's a really bad sign that you're burning oil. Black smoke is unburned fuel. You can easily smell both of these. If it's steam, you may have opened an area of the engine's head cooling system that has been completely plugged for a while and only minimal water is flowing through that section and causing steam. When an engine emits steam, there's no petroleum odor, but there can be some nasty smells from marine critters and scum.

You may want to run another batch of acid through the cooling system, which could open up some tiny openings in the engine's head, and this may even solve the steam problem. Can't hurt.

Keep in mind, however, that the acid eats away at rust and calcium crud that builds up throughout the cooling system. Some of that rust, especially in a raw water cooled engine, may have eaten away at the engine to the point where the rust was the only thing holding the engine together - somewhat like the cars I owned when I was young and poor.

Good Luck,

07-07-2013 08:34 PM
Re: atomic 4 cooling system

Well I ran muratic acid thru my atomic 4 today. The water is definitely going thru the cooling system much better. However there is still a lot of white smoke (which I thought was steam). Can anybody offer me some tips or ideas? I changed the oil but thought maybe I should a compression test? Thanks!!
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