Antifreeze/Engine Coolant

[Anonymous Poster]

Not to answer for Richard...

Most of the newer automobile engines have alot of aluminum that requires this extra silicate that is detremental to diesel engine/radiator passages...{note clogging etc.}

For some reason, the off the shelf antifreeze in the stores is by far cheaper to buy then the pre-charge for diesels...{not that it should be? Supply/demand principle?}

On the same token, you can have one case of diesel oil for everything... /w3tcompact/icons/blush.gif {again more expensive...}

 

[cowboydoc]

Yea I agree with John you are talking about a completely different system that requires different coolant. Stick with the regular prestone etc. for the gas engines.

 

[gsxr1100]

Mike--That is a no on the same coolant with precharged, in general; however I do this with my cars, motorcycles, etc.

I use the Fleetguard Fleetrite antifreeze for diesels in everything. This antifreeze has no charge in it. The stuff is for diesels but you can use it in all cars or anything because all cars and trucks have aluminum in them. The diesel part of this item makes it have low silicate and conform to GM specifications. Just add the antifreeze mixtures and then add your SCA to the diesels only. The engine will be very happy.

I have done this with all equipment and the rads stay very clean. When you look inside the fins are as clean as ever!

**Side note: Ford had a TSB on 1997 thru like 1999 taurus 's that had to have the SCA's for diesels added to it! They had a problem. That is Ford. Also to add that 99.9% of dealers never add the SCA to coollant to start with.

I would tell all diesel owners to check the coolant with test strips. You don't need a liner to blow out (or in)


Thanks
Mike

 

[RPM]

The erosion is caused by a phenomenon known as 'jetting'. The bubbles collapse when they get hit by the pressure waves passing through the fluid in which they are suspended. The bubble doesn't burst as a balloon would - but instead it collapses asymetrically.

In laymans terms imagine a pretzel shape (the curly ones not the pretzel sticks). This is roughly what a collapsing bubble looks like in cross-section. One side of the bubble folds in on itself.

The result of the bubble collapsing in this way is that a fluid jet is rapidly expelled by the collapsing bubble. This is the fluid caught between the collapsing halves of the high pressure gas bubble. The fluid jet will typically achieve supersonic speeds (i.e. faster than the speed of sound in the fluid in which it is travelling). When the supersonic jet hits a solid surface you get a nice little shock-wave interaction that pits the solid surface.

This is the same principle that is used in HEAT (High Explosive Anti Tank) rounds - the principle of shaped charges. In the case of HEAT rounds you can use a copper shaped charge liner to penetrate armor-plate.

Fun stuff.

Patrick

 

[Rch]

What does SCA mean.

RCH

 

[Bird]

<font color=blue>What does SCA mean</font color=blue>

Here's what one company says about it (talking about Fords):

"Supplemental Coolant Additives (SCA's) are important to ensure long diesel engine life. Their primary function is to protect the cylinder wall from cavitation erosion (pitting). Secondarily, they bolster the anti-corrosion additives in antifreeze. The purpose of SCA is to prevent cavitation erosion of the cylinder lines. The additive concentration should be checked every 4 months to assure that it is properly maintained."

 

[TWINKLE_TOES]

John,
<font color=blue>... an "electrolysis type action" results... </font color=blue>
Can you provide further insight or references to this phenomenon? I would like to know more. Thanks in advance.
Al

 

[TWINKLE_TOES]

Patrick,
<font color=blue>The erosion is caused by a phenomenon known as 'jetting'. </font color=blue>
I would like to know more about this, can you provide a reference that explains this and the fluid properties that allow it to occur. Thanks in advance.
Al

 

[RPM]

I'll hit two birds with one stone here ...

First note that John Miller's note refers to an "electrolysis like" action. This refers to a mechanism similar to spark erosion. It does not indicate that the pitting caused by cavitation is due to spark erosion - just that it produces similar results.

Second, with regard to my comments about erosion due to jetting ... I'll give a brief description, but you won't find much (if anything) in the public domain on it. You could try a search on 'bubble micro-jetting cavitation' to see what comes up but it won't be very much. The military is very familiar with this concept.

Basically, cavitation occurs at areas of low pressure within a liquid. The low-pressure allows microscopic bubbles to form of the vapor phase of the liquid.

When a shock-wave in the liquid impinges on these bubbles the bubble can collapse asymetrically. Not to trivialize, but the bubble first starts to look like a kidney shape as the shock-wave hits it - then as the shock-wave passes over/through it it starts to look more like a pac-man profile. The 'mouth' of the pacman would be at the opposite side to where the shock-wave hits the bubble first.

Now imagine what happens to the liquid caught in the 'pacman' shaped bubble's 'mouth'. The bubble collapse forces the liquid to accelerate to extremely high speeds - typically supersonic. This creates an effect known as jetting or micro-jetting (on this small scale).

The jet reaches extremely high speeds. When the bubble collapses in close proximity to the cylinder wall, the jet will impact the cylinder before it has lost any energy. The energy in the jet is such that it will hydrodynamically penetrate the material in the cylinder wall.

This is not melting or abrasion. The momentum of the jet is high enough that the target material simply flows away from the point of impact. This results (for a micro-jet) in a little pit on the target. Materials behave very differently under these high strain-rate / shock-wave conditions than they do normally. The effect is literally like aiming a high-pressure water-jet at a mud bank.

The end result looks similar to spark erosion, but under microscopic examination they look quite different. Spark erosion produces localized melting and other thermal effects. Micro-jetting does not.

This jetting mechanism is similar to that used for armor piercing munitions by the military - hence their interest.

Patrick

 

[Anonymous Poster]

Many things are occurring at once within the cooling system… electrolysis is only one factor. Anytime you have a mixture of water and dissimilar metals, you have this chemical reaction called electrolysis and you have the start of a miniature battery…

With the water flow throughout the cooling system, you have this turbulence causing erosion of the passages… and with the radiator and engine dissimilar metal particles suspended in the antifreeze and movement all combined produce the electrolysis effect.

Without the proper antifreeze and additives, you end up with corrosion of the internal cooling area along with cavitation, pitting, etching, jelling, clogging, and harmful deposits…

The bottom line… just like you change your oil in the engine on a regular basis to remove all the harmful impurities… you should change your antifreeze every 24-36 months for the same reason.

Changing engine oil and antifreeze on a routine schedule is the best and cheapest insurance you can give your tractor’s diesel engine for a long and happy life…