Chemicals for flushing out cooling system of indirect cooled engine

[Dull Spark]

The coolant in my Beta 30 has been OAT antifreeze for years and has been changed regularly.

This year, I notice that there are soft deposits in the coolant. They managed to block to overflow pipe on the pressure cap.

I'd like to change to inorganic coolant, but need to flush out all of the OAT. It will take a few flushes to get it all out (calorifier too), but i'd appreciate some advice on the use of any chemicals to help flush.

I am thinking of washing soda because I don't want anything too aggressive attacking the copper heat exchanger.

Any thoughts or advice?

 

[Skylark]

In the last 5 years, I’ve flushed three different old car engines using soda crystals, bought for a pound or so from the supermarket. All had iron blocks, two had aluminium heads.

Drain the old coolant, fill with soda crystals in a saturated solution, drive the cars for 2-3 days then flush with fresh water. One of the three required a second application.

New coolant nice and clear after a few years use.

 

[Refueler]

Furnox Home Heating system cleaner .. can be had in various formats depending on alloy / iron etc.

Rydlyme ....

There are many products to do the job ...

 

[NBs]

Valvoline has this cleaner

Cooling System Cleaner - Valvoline™ Global Europe - EN

NBs

 

[Dull Spark]

Many thanks. To be frank, my chemistry knowledge is poor. The soda packet warns against use with aluminium. The Valvoline product data sheet recommends to avoid use with aluminium, copper or copper alloys.
I don't know if there is any aluminium in a Beta cooling circuit, but the heat exchanger looks like copper or brass or bronze.

I had thought of dishwasher powder, but it's strong stuff and none of my crockery is copper!

 

[Refueler]

Many thanks. To be frank, my chemistry knowledge is poor. The soda packet warns against use with aluminium. The Valvoline product data sheet recommends to avoid use with aluminium, copper or copper alloys.
I don't know if there is any aluminium in a Beta cooling circuit, but the heat exchanger looks like copper or brass or bronze.

I had thought of dishwasher powder, but it's strong stuff and none of my crockery is copper!

Check with local Central Heating guys - they have cleaners that cater for all manner of metals .... as in the range of Furnox I mentioned earlier ...

 

[thinwater]

The coolant in my Beta 30 has been OAT antifreeze for years and has been changed regularly.

This year, I notice that there are soft deposits in the coolant. They managed to block to overflow pipe on the pressure cap.

I'd like to change to inorganic coolant, but need to flush out all of the OAT. It will take a few flushes to get it all out (calorifier too), but i'd appreciate some advice on the use of any chemicals to help flush.

I am thinking of washing soda because I don't want anything too aggressive attacking the copper heat exchanger.

Any thoughts or advice?

I spent my career in engine coolants and have two formula patents.

• Flushing chemicals are generally a bad idea unless you really need them. NONE of them are good to have in the system and they are difficult to flush to the ppm levels required. The marketing department likes them a lot more than the engineers and chemists.
• Don't DIY. The chemicals need to be compatible with the formulation that is going in next. Washing soda, for example, is not a good choice.
• Identify the deposits. Are they soft, like over concentrated organic additives? Maybe the concentration was too high. Maybe there was lime in there from using tap water (you didn't do that, did you?). If this is the case, the best flush is DI water. Run plain water in the engine for a few days and they will probably dissolve on their own.
• Are they hard? The cause of corrosion is most likely not the coolant, but either stray current or an air leak (oxygen in the coolant is very bad). Has anything been re-wired? Is there a hose lease or cylinder head leak? Is the coolant rusty (rusty appearance is always either air or current with modern coolants).
• In general I would NOT advise going to inorganic coolant. It is not as compatible with seawater leaks and it needs to be a diesel (not auto) formulation.

You might also test for chloride. You may have seawater in the coolant, which can cause this and is very bad on the engine side.

But flushing is ONLY required if there is another problem. The coolant by itself won't do that. Obviously. There is no reason to change coolant types and no manufacture wants to go back ... or they would to reduce warren tee problems. The negatives of organic coolants are a combination of urban legend and blaming the coolant for other problems. There were actual problems the first 5 years or so related to silicate cross-compatibility, but those are in the rear view mirror decades by now.

 

[Refueler]

Most indirect coolant fluids - anti-freeze - have various anti-corrosion / cleaning agents included to a minor degree. This is not only to lessen internal build up of crud - but also allows use of typical Tap Water ....

 

[oilybilge]

Maybe there was lime in there from using tap water (you didn't do that, did you?)

 

[thinwater]

... but also allows use of typical Tap Water ....

No.

If you read the specifications for makeup water, they are very similar to battery water. This is why nearly all coolant is sold as pre-dilute now; tap water can ruin it. It really needs to be distilled or very similar.

The UK engine coolant standards group merged with ASTM several decades ago.

 

[Refueler]

Oh Dear "Thinwater" ....... please go back and read fully my post ...

Anti-freeze has in its blend anti-corrosion and cleaning agents .....

But lets also move on - and that most cooling systems - people will fill with Anti-freeze blends straight out of cans bought in local car shop / petrol station. The days of just putting in water are pretty well history - unless living in high temperature climate where Anti-freeze is not needed.

Next - I would really like to see an example ... lets say a can of water sold just for cooling systems .... I'm 68yrs old ... driven in many different countries around the world ... and never seen water in cans sold for this purpose ...
I've seen plenty of jerry cans filled from well pumps ... taps and springs ..... carried by vehicles going off across dry plains etc.

But anyway - regardless of the last couple of points I make here ... the Anti-freeze as I said clearly offsets by its additives the tap water...... if tap water is ever introduced to the system.
The amount of build up from Tap water as you implied by your first mention of it ? Would be very limited .. I would suggest tiny in fact ...

 

[thinwater]

Oh Dear "Thinwater" ....... please go back and read fully my post ...

Anti-freeze has in its blend anti-corrosion and cleaning agents .....

But lets also move on - and that most cooling systems - people will fill with Anti-freeze blends straight out of cans bought in local car shop / petrol station. The days of just putting in water are pretty well history - unless living in high temperature climate where Anti-freeze is not needed.

Next - I would really like to see an example ... lets say a can of water sold just for cooling systems .... I'm 68yrs old ... driven in many different countries around the world ... and never seen water in cans sold for this purpose ...
I've seen plenty of jerry cans filled from well pumps ... taps and springs ..... carried by vehicles going off across dry plains etc.

But anyway - regardless of the last couple of points I make here ... the Anti-freeze as I said clearly offsets by its additives the tap water...... if tap water is ever introduced to the system.
The amount of build up from Tap water as you implied by your first mention of it ? Would be very limited .. I would suggest tiny in fact ...

You defending an untenable position. This has been debated to exaustion by the standadrs organizations, which include users, manufactures, and OEMs. Yes, I read the full post, and that first line is basically not true. The are NO CLEANERS in engine coolants. In fact, dirt ties up anti-corrosion additives, reducing protection. Also, engine coolant (note that it is not called antifreeze) is required in all climates for corrosion protection, cavitation protection, and vapor pressure reduction. In the US at least, the required service concentration is the same in all 50 states. There is also no provision in any of the standards for reducing the concentration. It doesn't work that way. In some cases, industrial engines use water with additives, but the concentrations are the same and not all manufacturers like this practice (the system must run at a higher pressure).

Yup, there are lots of things you can do. And they often have consequences down the line.

The other factor is seawater leakage. Although extended life coolants are common in cars, you will find the engine manuals for marine applications recommend changing every season, and the difference is seawater. Lots of calcium, lots of chloride, and cross contamination potential. Or you can test the coolant for seawater.

This is my home turf. Yes, I have seen damamge caused by relatively small amounts of tap water. I've seen damamge caused by mixing types. One of the most common problems is lumpy deposits that clog vents. This is why the standards changed.

 

[Refueler]

What a load of .....

Thinwater ... I use the term Antifreeze - as that is the product that people take off the shelf to put in their systems ... of course in climates that are not subject to cold / freezing winters - then the product would be called Coolant or some other name ...

Having setup - owned - run labs for many years - I'm not talking from a position of no knowledge ... you seem to forget that. I was also a Consultant Member to ASTM ... a Senior manager in BSI ... so we can dispense with your CV quotes ... Having served in those capacities - I am well aware that those organisations do not in any form listen to ONE person - every standard / every action of those organisations are based on repeated data over significant periods before they even get near to consultant discussion ... so we can put that little bit to bed.

Call the product by whatever name you like .. - it DOES carry cleaners as well as the inhibitors both you and I have mentioned.

You may wish to continue your stance ... go ahead ... I'm not interested any further .. I've stated in simple terms fact. I shall leave it that.

 

[thinwater]

The official name on every bottle, in your manual, and in every standard is engine coolant, and has been for about 30 years. Antifreeze is the stuff you put in plumbing.

Let's not throw mud or measure each other. It's a waste of time. I believe you are a smart guy.

---

As for the OP, the point I was making is that the coolant did not foul up on its own. No good brand does anymore. There were some problems when the OA product technology was immature, mostly the result of relying on lab work and not investigating the effects of contamination as it occurs in the field. Bad water, trace oil from the engine build, and mixture with silicated coolants were the two classic problems. All the testing was done with laboratory-clean engines, and then the factory dumped it into engines with oil in the bores. But this is in the past and he has changed the coolant several times, presumably sticking with one product. There is another problem, but not nearly enough information to diagnose it.

Personally, if analysis was not available to me (there are cheap test tapes) I would run the engine on DI water for a few days and then change. If there are soft deposits from the OA gelling, that will solve it. If he has another problem, the test results may give a clue.

 

[Refueler]

"Antifreeze is the stuff you put in plumbing."

Ha Ha Ha ... tell Shell ... Halfords ... Lukoil .... Viada ..... BP ..... Chevron ..... and thousands of other brands ...

For many decades variations of Glycol have been used .... with later concoctions expanding the range outside of the traditional Glycols ...

On that fact - I shall depart ....

 

[PaulRainbow]

"Antifreeze is the stuff you put in plumbing."

Ha Ha Ha ... tell Shell ... Halfords ... Lukoil .... Viada ..... BP ..... Chevron ..... and thousands of other brands ...

For many decades variations of Glycol have been used .... with later concoctions expanding the range outside of the traditional Glycols ...

On that fact - I shall depart ....

Personal/Recreational vehicles

Coolants – Antifreezes – Iada

https://www.bp.com/en_ae/arabia_lub...al-vehicle-oil-and-fluids/engine-coolant.html

https://www.shell.co.uk/fuels-oils-and-coolants/shell-engine-oils/coolants.html

https://www.halfords.com/motoring/engine-oils-and-fluids/antifreeze/

Every single ones uses the term "coolant". A couple also mentions "ant-freeze", but coolant is always in there.

In many cases it isn't there to protect from freezing, but to protect from corrosion.

 

[Refueler]

Personal/Recreational vehicles

Coolants – Antifreezes – Iada

https://www.bp.com/en_ae/arabia_lub...al-vehicle-oil-and-fluids/engine-coolant.html

Shell Coolant | Shell UK

https://www.halfords.com/motoring/engine-oils-and-fluids/antifreeze/

Every single ones uses the term "coolant". A couple also mentions "ant-freeze", but coolant is always in there.

In many cases it isn't there to protect from freezing, but to protect from corrosion.

Its a funny world isn't it ...

As you correctly say - Anti-freeze / coolant call it what you will - is not only protection against freezing - but a provider of inhibitors .... and those inhibitors are far more than just corrosion ... THATS my point ...

I am old enough to remember AND to have used concentrated Anti-freeze - that was the name on the can ..... which required diluting to the level of protection you wanted ... guess what - it NEVER said to use any special water ... we all just got our watering can of tap water and topped up the system with that diluted mix ... funny old world isn't it ...

Boat engines ... how many use tap water via a hose or bucket for flushing engine out at end of season ? How many top up their systems during use with tap water ?
Don't forget that the engine block / head etc are same whether raw water or indirect cooled for majority of engines we use ... so raw water cooled has sea-water passing through (set at cooler temp of course to reduce depositing the salts) while same block / head on an indirect has 'fresh water' mix passing through it ... strange old world isn't it ... unless of course you fill with .. whats' that word on the can again ??

 

[Dull Spark]

Many thanks to Thinwater, Refueler and Paul Rainbow. For 7 years I have always bought the same Halfords antifreeze/coolant that the boat's previous owner left when he sold it. It was the same colour as the stuff in the engine, but its possible that he had just changed from a different type and I've been wrong all these years. In any case, it is hard to flush the old stuff out completely when I do a change. (Every other year at least, but not always every year. I did buy the concentrate, but used demin/deionised to mix it to 50:50. I may have put in more coolant than demin, but not much more. I haven't topped up with ordinary water.
The deposits are soft and, as I said originally, have blocked the vent connection from the engine - I had to use a cable tie to clear it out. I'm worried about what else they may have blocked.

I think the advice to run for some time just on demin water is good. I appreciate that coolant also helps with heat transfer and prevents cavitation, but its a Beta 30 - a Kubota derivative. The engine is used on farms and construction sites the world over and is fairly basic - not Formula 1. So if i don't hammer the engine, I think I should be OK.

It's not impossible that I've has seawater contamination. To be frank, I don't know which circuit is at the highest pressure: seawater or closed circuit. And it may change as the temperature rise and falls.

By the way, I bought coolant directly from Beta in Gloucester last month and intend to use this after the flush out. It's on the boat now and I think it is inorganic. I'll let you know.

It's been a pleasure learning - every day a school day!

 

[thinwater]

BTW, cavitation is not a Formula 1 thing, it is an HD diesel thing. The pistons slap the wall and cause cavitation on the reveres side. In general, it is a problem only with wet sleeve engines that are run at high load factors. OA coolants do better than inorganics. It is a very uncommon problem in recreational boats, but not unheard of and is considered in the coolant spec.

 

[billskip]

unless living in high temperature climate where Anti-freeze is not needed.

- is not only protection against freezing - but a provider of inhibitors

inhibitors are not needed in high temperatures....is that what you are saying?
My experience in high temperature countries was coolant (antifreeze/water 50/50 mix) was required and recommended by the car manufacturers.
I also found that the recommended mix had better cooling than just water.