Change the coolant once a year???

[Genesis]

It looks pretty good, but I don't see the DD number. That may be an omission, or it may be a problem - I have no way to know.....

Try calling them?

 

[ADaily3224]

Karl,

Thanks for update and warning about the permanent Cat AF. I have white absorbers under the engine and gear and check them every time I go for a run, that bright orange-red AF shows up very well if there's a leak. So far so good. My previous boat had 671's and I did exactly as you suggested, had a winter and a summer AF mix. When I sold the boat with the 671's I explained to the new owner the procedure for taking out the winter mix and pouring in the summer. They forgot, got a few miles away on Lake Ontario and overheated, I had almost straight AF for the winter mix. They had to be towed in by the coast guard. I guess when my permanent wares out I'll go back to the old plan as you suggested.

Tony D

 

[Genesis]

That's ok.

When I sold Gigabite I had water + SCAs in both mains. She ran nice and cool on sea trial. We were in the bay for over an hour and on the pins for a good 5-10 minutes; never went over 180F and around 175 at cruise - right "up the middle" and where she usually was.

Apprently, fouling grew in one of the H/Es next few weeks + warmer raw water, or something got sucked up into one side's intake, after the closing. The buyer called me and asked if it was normal for one engine to run 10 degrees warmer than the other. Uh, no, its not. (Given that it was one side, I suspect the cause was something in the system that shouldn't have been there. Fouling don't grow in only one side, generally.....)

Anyway, he had someone take a look down the H/E inlet and saw nothing obvious, plus checking the impellers, etc.. But - said "mech" pulled out his handy dandy AF tester, saw no freeze protection, and immediately proclaimed that was the problem and got the owner to agree to let him do a coolant change (!) Now remember, I had put that water + SCA change in there less than six months before, and this was one of the things I talked with the buyer about at some length, so he understood that he had no freeze protection AND WHY. Nonetheless, Mr. Mechanic "won" and billed him for 5 gallons of concentrate, the water, and the labor. (One hopes he didn't screw him on the labor charges, considering that I had ball valves on both drains - it took less than 10 minutes to drain the cooling system on those enignes as a consequence so long as you had a couple of 5 gallon buckets and a piece of hose!)

Anyway, post putting AF back in the engine it ran HOTTER! (duh!) I next got a call a couple more weeks later and this time they were in the gulf with the overheat alarm going off on that engine! We went through what they had done, and I swore lightly under my breath..... there's no way you can fix an engine running warm by REMOVING cooling capacity! Said Mechanic had done a bad thing, and the alarm likely saved this guy from a cracked head....

THIS time they tore down the H/E involved and acid dipped it. The problem disappeared. I have no idea whether it was some nice piece of seaweed or grass that lodged itself expertly in the core, or whether it was just ordinary fouling, although I have my suspicions given that it was ONE engine instead of both....

Anyway, the lesson here is that AF conducts LESS heat than water + SCAs, and when you have an engine with marginal cooling capacity to start with, as high-output Detroits have, and you run in 85F raw water, you need all the advantages you can get!

 

[Trojan]

I'm NOT disagreeing with you Karl. But when I asked my DD dealer what antifreeze should I be using. He said any good grade diesel 50/50 mix is OK. I didn't need to use just there brand of DD. He said It would cost less if I would get it at a big truck stop down the road. I even mention what you said Karl. He said it didn't matter. Just make sure it was a 50/50 mix and don't buy the cheap crap. That was from 2 of the larges DD shops in Toledo.


BILL

 

[Boatsb]

Just a little science here guys.

At 25% concentration Ethylene Glycol based Water Solutions have a specific heat capacity of .95 at 200 degrees F.

50% Ethylene Glycol based Water Solutions have a specific heat capacity of .865 at 200 degrees F.

Thats a significant differance ( about 10% ) if my calcs are correct.

Water FYI has a specific heat capacity of 1.005 at 200 degrees F. 5% better than the 25% ethylene Glycol.

Karl is right and its best to use the H2O and SCA in non freezing environments. The guy at DD in toledo may not take into account the warm weather use of the boats.

 

[34Hatt]

Genesis Anyway, the lesson here is that AF conducts LESS heat than water

Yup That is why a lot of oval race cars will run pure water!
I learned that when I had a small block running 12.5 to 1 compression in a Willys with a small grill opening that puppy was tough to keep cool . Learned a lot about cooling tough .

 

[Boatsb]

I had an old 63 willys pick up with a 6. Worked to the B$^%. Pistons, Cam, Carb. Converted to alternator and then back to the generator for waterproof needs out in the mudflats in Patchogue.

 

[34Hatt]

I had an old 63 willys pick up with a 6. Worked to the B$^%. Pistons, Cam, Carb. Converted to alternator and then back to the generator for waterproof needs out in the mudflats in Patchogue.

Hey I will PM you I grew up in Patchogue and came real close to getting my Willys stuck there!
Mine was a 1960 Panel 2 wheel drive Chevy small block that was painted two tone Blue. This was back in early 80s.

 

[ELECTRA VI]

My Yanmar engine manuals specifies that I change the coolant annually and specifies the Texaco premix coolant. I have been doing this religiously since the engines were put in in 2003.
George Jeandheur
ELECTRA VI
1966 34C #068

 

[DickB]

The subject has not yet come up, but does anyone "flush" before draining the system? The DD shop up here has two varieties. One which can be left in the engine for a one week cruise, a second which supposedly needs only a few hours to work. Not sure what this really "cleans out" but they recommend it before draining.

Dick

 

[Boatsb]

The detroit service bullites ( at least for the 53 series) have a test procedure for determining if a flush is necessary. Basically its opening the wate pump inlet or outlet or another accesable spot and touching the "coating " in there. If its rusty and hard to wipe orr flush with chemical. If easilly removed basic flush and refill. Check the bullitens.

 

[Passages]

Dick,
If you scroll up and click on my link, you'll see that Texaco is recommending only a water flush between changes. Commercial flushes are only to be used if there is considerable sludge in the system.
One engine drained out some black sediment so I'm using a cleaner flush on that one, the other looked OK so it just gets water.

 

[DickB]

Ok. So you drain, refill with water and warm it up. Then drain again and add the AF+water. Correct?

Dick

 

[Boatsb]

I just cleand the heat exchanger so I drained the FW system. Filled it with distilled water. Ran. Drained again and had clean water so I refilled with Distilled/SCA ( Napacool)

test strips showed good levels and I'm done.

 

[Norm Mayer]

I just cleand the heat exchanger so I drained the FW system. Filled it with distilled water. Ran. Drained again and had clean water so I refilled with Distilled/SCA ( Napacool)

test strips showed good levels and I'm done

Just as previously mentioned, DISTILLED water and an SCA like Napacool is one of the best allaround results. Water is the best at moving heat (the prime purpose of coolant) and use distilled, as it has no minerals to create deposits. As earlier mentioned, use an additive package, because it includes water pump lubricants, anticavitation and other important additives. The test strips mentioned are a must. Coolant does not need to be changed every year or two, but the additives NEED to be replentished regularly. The strips will tell you when, and how much additive to add.

If you also need freeze protection, then obviously, coolant must be used, but again, you MUST keep up with the additives, and special test strips must be used to test that coolant for proper additives. My present coolant is 8 years old, and is finally needing replaced. Since I live in SW Florida, it is straight distilled water and additive package (NAPACOOL and the test strips is easy maintenance)

FWIW

 

[Passages]

DD 7SE298, which is the applicable spec. If that stuff doesn't have that approval on the label, take it back.

Just to wrap this thread up, Texaco HD has the 7SE298 designation. Though not noted on the gallon jug or the spec sheet, there it was in black & white on the outside of the case duh.

For once the cheap stuff can be used on a boat. I picked up 9 gallons at the bargain price of $7.18 each at Advanced Auto.

 

[Genesis]

Cool(ant)!

 

[(Nobody You Know)]

I just cleand the heat exchanger so I drained the FW system. Filled it with distilled water.

Either been too lazy to locate this, or didn't think it was that important, however had always heard it was best for lead acid batteries. Question is, what is a good source for disilled water??? (short or a bucket out in the rain, and why wouldn't well water work?)

Capt'n Bill

 

[Genesis]

You buy distilled water from the store.

Rainwater is possibly ok. Well water is NOT - it typically is LOADED with minerals.

Those will drop out in the piping and create scale problems which are difficult to fix (you need to acid-wash the engine to fix it.)

 

[MikeP]

Any supermarket should carry distilled water in gallon jugs - it's usually in the section with the stupid water (bottled water that, although very popular for some reason which TOTALLY escapes me, meets lesser health requirements than what comes in your tap). Sometimes distilled is in the section with laundry stuff because it used to be recommended for use in steam irons. Don't know if it still is. Probably not since no one nowadays makes a product (steam iron) that will last long enough to make regular/distilled use an issue.

Well water - depending on where it's from - can be chock full of minerals so it would be a very bad choice for coolant. If you have a dehumidifier in your house, the water it produces is distilled and can be used for coolant/battery replenishing.