How can we prevent, diagnose, and eliminate overheating problems?

[swatski]

geez louise!!! These pictures are giving me PTSD I won't be able to sleep tonight.
I've been flushing my engines religiously with Salt Away, hoping the solution works as it is supposed to - prevent corrosion and built up in the cooling passages. I have hose pressure strong enough to push water through the pissers, that is until engines warm up and thermostats open?

Would doing this (below) all the time stop the misery?


Okay, somebody with a twin needs to do the controlled experiment: flush one motor after every ride with S-A, one side only, leave the other side alone, then pull the head in a couple of years. Any volunteers?

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[WREKS]

@swatski Good to hear from you.
The algae condition is much more evident in dry sump engines with oil coolers because of the large forever wet internal surfaces. The head does not have to be pulled. If the engine has an oil cooler, and if there is an algae buildup, removing an accessible oil cooler cover will reveal it.

The algae builds up when the engine is not running. I know because I had removed the engine to address a problem and while I was correcting the problem I removed the oil cooler including covers and thoroughly cleaned everything. At that time it had algae on it. After that, I reinstalled the engine, put the boat in the water, ran it for 17 miles, at 7k with no issues. That was the last day of April 2020. Boat has not been used since then except to exercise the engines on the hose twice a month for 10 minutes each.
It was during the second to the last such exercise that I noticed that the thermostat was not fuctioning. I removed it. It had a buildup soft stuff on it. I wondered what the oil cooler might look like inside.

This reminds me of @BrentEB 's thread "Ok, What are my chances on cleaning up salt plugged block coolant passages?" post#44 where he says

buckbuck said:
That is a big clump of sand. Are you confident you got everything around the cylinder walls?

"An update: It's not sand. But the quick answer is "No". What I've found is that is the past 4 times I've tried to go out more of the crap flushes out and plugs the thermostat. Pull the thermostats and clean, flush, then ok. But next time going out a week or so later more crap plugs the thermo again. Flush & clean, repeat cycle. It will eventually all come out. If you read the Salt-Away lit that's how it works."

If you substitute "algae" for "salt" and "crap," the issue is the same.

 

[swatski]

Cool. I'll keep flushing with the Salt-Away, gotta trust the chemists and their corrosion protection claims; I buy that stuff by a gallon now which makes it affordable. Seeing what it does to when used on salt dried up on the hull and trailer is very encouraging. By comparison, my home brew saltaway cocktails (oxalic or sulfamic acid mixed with car wash detergents) just don't seem to give the same effect, the commercial S-A leaves surfaces feeling cleaner if that makes sense.
I'll save my home brew mixes for washing the hull in between fresh water wet slip periods, works well there. But I'd want the best for salt corrosion prevention in the engine blocks and there is no point of trying to save money on the best commercial product.

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[WREKS]

@swatski Any safe chemical(s) that upsets the natural environment for algae is favorable. I would like to leave some of that chemical(s) behind in the cooling system after flushing. I am experimenting with white vinegar. It is so affordable. And, it is what the AC tech suggested to help keep the condensate line from plugging - ½ cup, twice a month.

 

[swatski]

@swatski Any safe chemical(s) that upsets the natural environment for algae is favorable. I would like to leave some of that chemical(s) behind in the cooling system after flushing. I am experimenting with white vinegar. It is so affordable. And, it is what the AC tech suggested to help keep the condensate line from plugging - ½ cup, twice a month.

Salt Away is $45 a gallon... that's not bad given it contains corrosion inhibitors that are not easily incorporated into cleaner home brews, especially with the prospect of leaving some of it behind:

Amazon.com : Salt-Away Products Cleanser Concentrate : Boating Cleaners : Sports & Outdoors

Amazon.com : Salt-Away Products Cleanser Concentrate : Boating Cleaners : Sports & Outdoors

www.amazon.com

Otherwise, sulfamic acid at $15 to make several gallons of stock (concentrated) solution, which is the main ingredient of S-A would be my go-to, before vinegar:

https://www.amazon.com/gp/product/B001AZL24M/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1

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[WREKS]

@ swatski After taking the picture above, I reinstalled oil cooler cover and ran on hose for ten minutes using Salt-Away. I removed the oil cooler cover to inspect. The Salt Away had no effect. My conclusion is that once the algae builds up, it is not going to be chemically removed.
Generally, I think the cooling system can live with algae as long as it remains soft. Water flow pushes through it. It might plug up the t-stat a little, but that is liveable. If the engine does not overheat that is good. When it becomes the brown residue as in the picture at the begining of the thread, it has to be physically removed.
Again, my boat sits for long periods of time between uses. That leaves plenty of time for algae conditions to develope.
First I would like to determine if leaving some vinegar in the cooling system will alleviate the algae buildup. It is easy enough to check by removing the oil cooler cover after it has been sitting for a while.

 

[1WetBoat]

It sounds as if leaving the boat sitting for extended periods of times in a warmer climates promotes that algae growth. Regular use or colder climates might not allow it to grow enough to be a concern.

 

[WREKS]

@1WetBoat I exercise the engines every two weeks on the hose. That may enhance the algae growth by providing fresh water to the cooling system.

 

[swatski]

@1WetBoat I exercise the engines every two weeks on the hose. That may enhance the algae growth by providing fresh water to the cooling system.

Okay... on the topic of algae (cyanobacteria?) - their growth requirements other than warmth include sun/light and key nutrients like phosphorus and nitrogen. You are not using fertilizer to flush your engines? assuming there is not enough light coming through the cracks? Joking of course.

But in all seriousness, and I admit I have not looked if you already posted on any chemical analysis, but my guess would be insoluble mineral compounds such as aluminum oxide, not organic matter, constitute the bulk of what blocks the internal passages.

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[WREKS]

@swatsk Edited: This is organic matter. White algae vacuumed from an HVAC drain line

 

[Elliott]

It is obvious, your boat and house are possessed by some extraterrestrial being.

I do not think Salt Away is going to work.

 

[WREKS]

@Elliott That is not from my house. It is very common in AC condensate lines. I would ask an AC tech in Savannah about it. Please, give feedback. I never noticed a problem in Wisconsin, probably because the condensate line from the air handler drained directly down into the basement floor drain. In places without basements, where condensate lines do not drain as readily, and consequently get plugged, they have to be vacuumed out. This is what comes out.

 

[Elliott]

OK - whatever you say. At any point did you feel a stinging sensation on the back of you neck followed by a feeling of contentment?

Seriously, I realize that the goo was from an AC drain line; however, I have never seen anything like that here or anywhere that I have lived. My AC is serviced twice a year, and they just pour a little bleach water down the drain line to prevent any possible blockages. The treatment is to prevent algae/mildew/mold - not the intestines of some ET. My AC drain line runs from the air handler in the attic out to the wall (very slight slope) down the inside of the wall and outside about 2 feet off the ground.

 

[WREKS]

When the AC people told me it was algae, I didn't believe it either.

Edits added:

This picture was posted not to offend viewers, but to illustrate how invasive white algae can be. The same white algae that establishes and grows in the HVAC drain line, can grow in the damp and dark channels of the oil cooler. (See pictures in Posts 1,14)

I found this on the web at rasmech.com
September 25, 2019
Tim Seberger of Rasmussen Mechanical wrote:
"White slime is gross and is difficult to look at. Every time I see the goo, I fear for my life thinking that one of Ridley Scott’s aliens is hanging above me. I have to be brave though, I have to save my HVAC system.
WHAT IS THIS SLIME?
Let’s take a trip back to biology class for a quick minute. White slime is a build-up of microbial cells and water. Inside the gooey substance is a colony of microscopic single-celled organisms...You can anticipate more slime in any area that is dark and damp. If the slime is present, it can adapt to any living situation."

The picture posted above was not meant to offend someone's sensibilities but to illustrate the potential for this stuff to build up. Just like it invades an HVAC system, it can establish and grow in an open loop cooling system. White algae in the cooling system causes cooling problems leading to engine overheating.

 

[WREKS]

Salt in an engine can be flushed away. White algae cannot. They are two different issues. Once you take a boat out of the salt water and flush the engines, all is well. There are numerous members who always flushed their engines with salt eradicating chemicals and yet had overheating problems.
Why? White algae is one answer. How does it happen?

The white algae starts growing when the boat is sitting idle. Unless the cooling system is absolutely dry, the dark, damp environment for algae growth is ideal. I only had my boat in salt water for 4 hours and flushed it with a salt removing chemical before a 5 month hiatus. Then I removed the back oil cooler cover and found it covered in white algae as pictured in Post 14. During the hiatus, I was exercising the engines every few weeks for up to ten minutes apiece on the hose. I can only think I was feeding the environment for white algae growth. Here is what I scraped off the oil cooler cover before reinstalling it. It has already started drying out. White algae

It is soft. At this time, I am not sure what the gray flecks are. Here are some pictures of white algae as it dries: white algae drying 1, white algae drying 2, white algae before being pulverized, white algae (pulverized)

Even being after pulverizing soft small and larger lumps remain.

Half the pulverized portion is in water and half in vinegar. I am goint to let it set for a week and observe what happens: 2 white algae samples: one in water, one in vinegar

 

[Scottintexas]

Eliminating Overheating due to white algae buildup.
Recently, I had a problem with my home air conditioning. The condensate line got clogged, started to back up, and was leaking in the garage.
The service company told me that the condensate line can get clogged from algae growth and has to be vacuumed out if the algae builds up. The algae has a white slimy appearance. When I talked with the AC tech about preventing the algae build up, he suggested pouring a half cup of vinegar a couple times a month into the line where it starts at the air handler.

There are several photos at the beginning of this thread in post #1, they show a substance on the gaskets and the oil cooler cover. It does not appear to be sand, salt, or sediment. It is soft and white or clear like silicone. What happens with my AC condensate line leads me to believe that the same thing is happening when the engine is cold. After the engine stops running, the warm wet environment of an open loop cooling system provides the perfect environment for internal algae build up. Even if the cooling system drains down, there is still an abundance of moisture left inside the cooling water passages. Here is a photo of the portside oil cooler cover. Conditions: The boat sits covered along side my house; The engine bay is always dry; May 1, 2020 was the last time it was on the water; The oil cover was clean when I launched the boat to test run it after fixing a milky-oil problem; After that, the engines were run on the hose for 5-10 minutes apiece semimonthly during the lay up. This is what the oil cooler cover looks like now after running for 10 minutes on a salt removal solution.

View attachment 136392

I do not know what happens to the algae after it dries out, but I think it turns brown and scales, leading to constrictions in the water jackets. I have observed algae in a soft form throughout the oil cooler, exhaust cooling ports, both sides of the head gasket, and thermostat. It does not appear to present in the cylinder water jackets in the soft form. Along with sand, salt, and sediment, algae build up can contribute to engine overheating.

Now I am pursuing ways to prevent or eliminate internal algae build up. I am sure that flushing with dish soap, vinegar, and various products are beneficial. Recently, the portside thermostat plugged twice, when I began running the engine on the hose. The first time, I stopped the engine, removed the thermostat, and cleared the plug. The second time, while it was running. I used an air bulb to backflush the thermostat through the water pilot opening. That worked. I think compressed air could do the same. I have removed the intake screen, plugged the cooling water supply hole in the impeller housing, and filled the cooling system with white vinegar through the flush port. A week from now, I will drain the cooling system at the impeller housing, flush the engines with dish soap, and remove the oil cooler cover to see if any of the buildup pictured above gets removed.

Looking for ideas and suggestions.

Let me start out by saying i'm not saying your wrong just thinking outloud,

I'm very familiar with white algea/AC goo, my builder routed an AC drain into a bathroom sink drain under the counter, every few years it clogs up and I have to clean that goo out,

questions ?
1. Have you removed the oil cooler on the other engine to see what it looks like ?
2. I wonder if house water used via the hose has chlorine and every other chemical in it would kill any growth, the AC water is naturally occurring without any of those additives so I understand how it grows algae easier
3 with as many boats and skis running around why isn't this problem more prevalent ?



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[WREKS]

@Scottintexas Thanks for replying.
Answer to question #1: Without removing the engine, I could only remove the back cover on the oil cooler. However, the oil cooler picture in Post #1 has the white alage on it also. That picture was taken when I removed the engine in April of 2020. At that time, both covers of the oil cooler were removed and looked they same way. The algae turns brown and pulverizes as it dries out, but it is very soft at first. In fact it is visible on all the pictures in Post #1. The fourth picture in Post #1, labelled Some sand-sediment removed from cylinder water jackets.JPG, shows what I chipped out of the cylinder block water jacket after soaking it in vinegar. Adding "dried white algae" to that label might make it more correct.

Answer to question #2: I use city water to flush the engines. The picture in Post #14 was 6 months after 4 hours of brackish use and bimonthly flushes.

Answer to question 3: Along with running in the shallows and sucking up sand and sediment, I add white algae as a cause for overheating. But it develops and builds up overtime from sitting idle with the wet cooling passages never drying out.

Here is a picture of the collection of white algae after a two weeks of dring out. Half the sample was covered with water, the other half with vinegar. The water covered sample just went back to it pulverized state. However the vinegar covered sample produced a brittle, shell-like compound.
Dried white algae samples: one in water, one in vinegar After two weeks the water sample returned to it pulverized state; the vinegar sample became a brittle shell like compund.

 

[swatski]

I can not seem to open and see the pics in hyperlinks in the last post, but I did look at your earlier pics of what you call white algae. It definitely looks like an organic growth, a life form. I would agree there.

However, it's very unusual to have (mold - see below) growing inside an engine...
If I had that problem, I suspect only possible in a very warm and humid climate, I would try to bleach all of it first, flush out all the organic matter, then deal with any remaining mineral deposits using SaltAway or SaltOff or a homebrew equivalent (with sulfamic or oxalic acid).

For the record though, this white fluffy stuff growing in the darkness of your (wet) oil coolers is technically not algae. It could best be described as mold, or a type of fungus, an organism that like yeast is more closely related to the animal kingdom rather than plants; actual algae are plants - eukaryotic and photosynthetic organisms needing light for energy and growth, they may grow on top of your roof or the side of your house but definitely not inside enclosed spaces. To add to this confusion, what's most often called "algae" is actually not algae at all; it is cyanobacteria which, unlike algae, is a prokaryotic organism (no cell nucleus) like most of bacteria.

Either way, I guess it just goes to show our boats need "rode hard (before) put away wet".


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[WREKS]

@swatsi What you say is probably true. The "white algae" designation may be parenthetical. In Post #47 a technician, Tim Seberger refers to the growth as "microscopic single celled organisms." Another at Delcohvac says, "White slime may be found in many areas of your system, including the drain lines, evaporator pan, and condensate pump. This wet, dark, environment promotes the growth of microorganisms. In this case, the goo is protecting a colony of bacteria beneath it that enjoys consuming dust for food."

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[WREKS]

The last time the boat was on the water was eight months ago in April of 2020. Everything worked fine during a 17 mile test run. I do not have many opportunities to get on the water, so I thought it would be a good idea, to run the engines on the hose on a regular basis until I could get on the water again. That was not such a good idea. The starboard engine overheated. I immediately suspected white algae buildup and that is what I found when removing the cylinder head. White algae buildup in cylinder water jackets

My conclusion: If the open loop cooling system does not dry out, the wet internal conditions encourage algae buildup. By repeatedly running on the hose, I was providing an ideal environment for the algae buildup. I am not going to try to dry out the cooling system by running the engines without cooling water. However, I am going to try to dry them out with compressed air at two places: through the cooling water pipe that exits out of the top of the valve cover (that will dry the engine); through the exhaust water hose coming from the oil cooler (that will dry the heat exchanger of the oil cooler). This procedure applies to the MR-1 engines.