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I wouldn't get too carried away with hi flow stats. The reason for that is, you can actually have too much flow in a standard motor and cause over heating. Simply put, the water does not stay long enough in the heat exchanger ad does not get cooled enough. The high flows in Performance engines work OK because the vehicle also has a performance Radiator to suit and the engine water galleries have not been increased. So the pump needs to squirt more coolant through the engine and radiator to cope with the excess heat. Even a standard car engine can over heat if the water goes through it's standard radiator too fast.

I was working on a performance engine today on a drag car. Nothing spectacular. A cut down Ford Pop I have been helping a mate build. Anyway, I set up the thermostat for the fans today and was using the IFR thermometer to read the heat of the engine just under the thermostat. I had my hand on top of the stat housing and watching the temp rise. It got to exactly 85deg and then suddenly opened and my fingers got hot instantly. I was kind of expecting a slower rise, not the instant ouch that was hot response.

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Any chemical supply co will have it, white pages or google, you don't need to remove the ends unless you are planing to pull the core, just re-route the hoses or fit ones that will allow you to raise the ends higher than the core. ,Done slowly it wont overflow (bubbling) when the mixture is acting with the deposits. if it does just dilute the spillage with water and wash down anything that it dripped on. It wont harm paint. Lots of barnacles blocking off skin fittings this year, reducing sea water flow to pump.

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Get one of these - very cheap insurance for your engine:

 

http://aqualarm.net/cooling-water-flow-c-2/

 

This alarm has gone off in our boat at least a dozen times over the years - generally blockages with seaweed.

 

We have 2 screens, one close to the skin fitting and another after the salt water pump.

 

The second one is to stop the oil cooler getting blocked if any vanes come off the saltwater pump impellor.

 

Got the strainers from general marine services in Pakenham St

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Anyone know of a cheapish flow detector locally ?

My water maker overflows the tank when it's full over the side so I'd like to put a sensor on the overflow tube (12mm I think) so I can wire it to a small led light rather than have to go up on the foredeck to check

First world problem I know, but I'm just worried about filling the ocean with fresh water ;-d

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Anyone know of a cheapish flow detector locally ?

My water maker overflows the tank when it's full over the side so I'd like to put a sensor on the overflow tube (12mm I think) so I can wire it to a small led light rather than have to go up on the foredeck to check

First world problem I know, but I'm just worried about filling the ocean with fresh water ;-d

Looked for a while for the launch - and ended up buying an Aqualarm off the website. I found a few places that did Reed Switches that i looked at using but not easily...

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On glycol in coolant / inhibibitors

Glycol is to prevent freezing of the coolant - it does not reject heat as well as water.

A couple of boats I know use a coolant with no glycol at all in the keel coolers to allow for max operating conditions - running at 100% for extended duration while going nowhere.

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Its the specific heat capacity (Cp)

for water @95 deg = 1, for eythelene gylocol @ same temp = 0.66 (units BTU/lb. deg F)

 

So water is 1/3rd better at heat transfer per kg than pure glycol.

 

Very interesting.

I'm in the process of sussing our coolant. We only need the corrosion inhibitor aspects, not much risk of it freezing around the Gulf.

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Indeed, for engine cooling/corrosion prevention, you dont need much glycol in NZ. You most definitely should use some though, as it is a lubricant, corrosion inhibitor etc as well as an anitfreeze. Also, if the water in your closed cooling circuit is green, and you get a leak, it's easy to know that it was from the cooling circuit, not salt water, or even melted condensation/ice from the freezer hoses...

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Indeed we do have green coolant.

On that, I once had a reputable marine diesel mechanic inspect my engine. This was when we were scoping out my noise and vibration project and deciding to 'keep and fix' or 'blow more money than we have' a on a new engine.

 

Anyway, diesel mechanic said I should be using an orange (red) coolant, and not the green one. Comments were that it is available from BMT, and is the type used in VW's. I couldn't get to the bottom of why he recommended this and consequently haven't done anything about it. We've always been perfectly happy with our green coolant.

 

Any idea what that would be about?

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The red/green used to represent two totally different glycols. Ethylene Glycol is the common green antifreeze and is toxic to us both by ingestion and skin contact. Red used to represent Polyethylene Glycol and is None toxic. In fact, in Shampoo and other thing, it is called PEG. The two are very different even though the only difference in name is the poly part and the two cannot be mixed. And you may have heard some saying not to mix red and green.
But as of lately, I have found products that are red that are still Ethylene Glycol and I have mixed the two with no issues. So don't go by that any more.
The advantage of the PEG is that it will not kill Marine life. EG will and it takes very little to do so. So if you spill it in the bilge, it is not good to pump it over board.
 

A couple of boats I know use a coolant with no glycol at all in the keel coolers to allow for max operating conditions - running at 100% for extended duration while going nowhere.

 

Possibly a product made by Alfloc. It's the additive pack without the Glycol.
You are correct that Glycol does not take up heat well. In fact Ethylene Glycol is a good insulator. And hence why the best ration mox with water is no greater than 50%. Any more than that and the various properties it adds to a coolant start to reduce again.
There are also other Coolants made to the specs asked for by the engine manufacturer. They can be expensive and I doubt any better than anything else.

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currently in the usa

 

https://www.thoughtco.com/antifreeze-red-green-or-universal-726155

 

Our classic cars use an inorganic acid coolant and are bright green in color.If you own a 1976 Cadillac Coupe Deville or a 1957 Chevrolet Nomad two door Station wagon this is the type of fluid you'll see. Maintenance intervals vary between manufacturers, but are generally recommended every 3 years or 30,000 miles. It's important to follow these maintenance guidelines as the PH level of the antifreeze can change over time and become acidic. Regular fluid changes can prevent damage to the cooling systems most vulnerable component, the radiator.

 

 

KEEP THE EXTENDED LIFE ANTIFREEZE IN NEWER CARS

Just because we bought the universal style coolant for the classics doesn't mean we're draining the extended life coolant from our newer vehicles. In fact, our 2011 Jaguar XJ-Series uses the new organic acid technology, or OAT. This antifreeze is identified by its bright orange color.

 

The extended life antifreeze isn't recommended for your older classic cars, because it can eat away at older style radiators with lead based solder. Visit the repair section for more time-saving and valuable classic car maintenance tips.

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Managed to identify the problem by elimination, and fix it.

To recap, the engine was running hot, 100 deg at cruising revs.

 

Thermostat was fine. Pulled it out and tested it in a pot on the stove with a thermometer. Stamped to open at 76.5 deg, which it duly did, and with a smooth action.

 

Coolant pump was fine. Coolant was ok, but changed it anyway while I had everything in bits.

 

Basically it was a fouled heat exchanger.

 

Followed up on Steve's tip of the phosphoric acid. Couldn't find any of that, but did get some TRAC Barnacle Buster, which is basically branded phosphoric, with an associated price tag. Ovlov and a few other places stock it, buts its $240 for 5l (makes 25l), not cheap.

 

But it worked.

 

Got a length of hot water hose from Burnsco for $10, took the raw water hose off at the exhaust elbow and just before the raw water pump (after transmission cooler). Got both hose ends up nice and high, with the longer hose running into a bucket, and just poured the stuff through with a jug.

Bubbled away like a science experiment for an hour or two. No violent boiling or anything to worry about.

 

Tested the engine on the mooring, and took it for a blat today. Cruising revs it's now doing 72/75 deg, and at max revs is getting to almost 80 degs.

 

Am using an IR thermometer to verify numbers, about $45 from Supercheap Autos. The temp gauge still jumps around. We believe that is an earth fault, but the gauge is basically correct as verified by the IR thermometer. Within 5 to 10 deg.

 

Very pleased with the Barnacle Buster and the tip on the phosphoric acid, which lead to going down that path. Previously to clean the HE the owner had to physically remove it, pull it apart, clean it, find new gasket seals, re-assemble etc etc, so doing it in-situ is incredibly easy. Just needed a $10 piece of hose to make it doable, and the product.

 

Will now do it annually when I change the pencil zincs (they need to come out as the acid eats them).

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You can also use the following.
White Vinegar = Actic Acid. In fact, any vinegar for that matter, but White does not stink as much as brown. It is much slower to act, so you need to soak for awhile.
Citric Acid, which is also a Chelating acid, which means it likes Iron deposits. Once again, a slower acting and needs a little more soaking. But I particularly like using it, because it can be made much stronger than Vinegar. Citric acid comes as a White Granule and found at Bunnings as a Concrete Etcher in a small 500gram round container with a large screw on top. Simply dissolve by pouring warm water into it while stirring and when it won't dissolve anymore, that's about it. Don't get the water too hot, which will happily dissolve more powder, but the Citric acid will grow large crystals as the water cools to cold. It is so safe, you can lick your fingers afterwards ;-)
Another commonly used, but is a powerful acid, is Hydrochloric acid, also called Muriatic Acid. Sold at places like M10, bunnings etc. It is an acid that needs care in using, although the product is greatly diluted in the forms of Concrete leaner. It is fast acting.
Phosphoric acid is also found at all hardware shops and Chandleries as a Rust and rust stain remover. Often found under the brand name Tergo. Tergo have two types of Rust removers. One, which you do NOT want is a white liguid that dries to a hard black coating ready for painting. The one you do want is a clear slightly soapy looking liquid. It is non toxic to use, but still strong enough that you want to wear gloves and not to get in your clothes. It is a good product to keep on the boat for removing stains on Gelcoat and SST work.
The other place you can get Phosphoric Acid from in concentrated form is Hamilton Chemicals. Available in 5Kg and 20Kg. Actually, all the above are available from Hamchem.

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Thanks for report and the good tips on diff acids.

 

All acids in strong concentrations need careful handling.

 

I recall in my first year chem lab seeing acetic acid in our stores. Nice, vinegar, I'll have a sniff. I forgot to use the gentle wafting of the hand motion I had been taught. Nice Big Sniff to remind me of what I like on fish and chips. BANG. I staggered and would have fallen had I not caught hold of the lab bench. BTW MSG is a brilliant rust remover which won't eat metal. You need to soak the part for weeks though.

 

And one more story for fun and interest. A group of us were in an anatomy lab waiting for a tutorial on the human liver. The tutor brought it in, removed the cover and one of the students fainted right there on the spot. His lights went out instantly and he hit the ground with a huge THUD, not a gentle swoon I'd been taught by the movies to expect. He never came back to class.

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Hamilton chemicals will carry everything listed in this thread. Unfortunately couriering some of those chemicals is not so easy as they require certain safety measures to be met. The guys at hamchem are pretty good to deal with and the prices are astonishingly low compared to what you get from most other places. The guys at Hamchem will also advise on what safety gear and precautions you realistically need to take when handling the stuff. Remember that some of this stuff is fairly dangerous on its own, and having an accident with it and mixing, say, a bleach with an acid can be very much fatal. 

 

 

Wheels, is the red coolant not MPG based - as in monopropylene glycol - or  what is often food grade coolant? A very sweat but non toxic form of glycol vrs the polyprolyene glycol which is typically used as coolant, is highly toxic and kills dogs, marine life etc. 

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Used to be the case TT. We always had the rule of never mix different colours. But I have found that places like Super Cheap and Repco sell Green, Yellow, Orange and Red additives all being Ethylene  Glycol. This type of Antifreeze also usually has in it a little bit of Di-Ethylene Glycol which is also Poisonous.

 

Polyethylene Glycol is not very toxic and is used in cosmetics, Soaps, Shampoo and medicines.

Propylene Glycol is also non toxic and is used in some foods and cosmetics etc.

Polypropylene Glycol is a Polymer of Propylene Glycol and is also non toxic and is used in Paintballs among many other things.

 

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