Coolant Hose Leak

[MochetVelo]

My 1921 Peugeot has a slow leak from the hose connection where it joins the tube in cylinder head. The hose clamp seems tight. Could I seal it using some silicone or other type of sealant?

 

Phil

[misterc9]

Try Peremetex Aviation seal in the brush can. Clean the water neck and inside the hose end thoroughly. I wouldn't use silicone.

[Spinneyhill]

Do you have the right size hose on it? Also, are the clamps too tight? If so they can wrinkle the hose and tightening the clamp just makes it worse. Been there, on both counts.

[MochetVelo]

I removed the hose (which seemed a good fit) to discover a lot of oxidation in the aluminum tube. Upon removing the aluminum part itself, I was surprised to see it and the block clogged with a green gel. I used regular etheylene glycol 50/50 mix. Does this stuff have a reaction with aluminum?

 

I made the aluminum guide tube, as the original was missing.

 

Phil

 

 

[MochetVelo]

I did some more research, and am thinking the "regular" antifreeze may have reacted with the Evans Waterless Coolant I originally used. I read on the Evans site that their coolant is not designed for un-pressurized coolant systems, so I drained it out and substituted the 50/50 glycol/water mix, but without flushing the system. . Whatever of the Evans coolant that remained may have reacted to create a giant green blob.

 

Phil

Edited December 24, 2017 by MochetVelo (see edit history)

[Spinneyhill]

We have discussed Evans "coolant" in these fora before. The specific heat of Evans is 2633 J/kg.K while that of water is 4184 J/kg.K. So water is a far better coolant coz it takes >50% more energy to raise its temperature 1 Kelvin per kg of coolant than it does for Evans. So for the same cooling effect, you need >50% more Evans circulating than you need water.

[DavidMc]

Also , don't forget that the Evans will not work in a thermosyphon system, it must have a water pump.   

[Spinneyhill]

and it is specified for a pressure system.

[MochetVelo]

I wrote Evans to ask about this chemical reaction. Does regular antifreeze attack aluminum?

 

Phil

[MochetVelo]

I got an immediate reply from Evans (on Christmas Eve, no less!):  "Sorry this happened to your engine.  Evans coolant is compatible with 50/50 coolants, so I am not sure why this green gel formed.  I have cc’d our tech specialist, he might be able to help you.  Please allow him a few days to respond due to the Holidays."

 

I don't think this goop is in the radiator, but I'll try my best to get rid of it.

 

Phil

[nickelroadster]

Today aluminum block engines use a special coolant.  Something else I would look at would be whether you used distilled water for the 50/50 mix  because non distilled water would have electrolytes in it that could promote bimetallic corrosion.  Look at how many pieces of different kinds of metals are used as the more that are there, the more this kind of corrosion will be encouraged.

[Spinneyhill]

Ethylene glycol should not react with aluminium. Does that AF have any anti-corrosion additives? It is absolutely vital it does.

 

Galvanic corrosion will occur between dissimilar metals electrically connected in the presence of oxygen and an electrolyte = water. Minerals in water will make a difference if they are dissolved as ions, meaning they increase the electrolytic action of the water. Also important is if the water was slightly acidic from the start and how long the AF has been in the engine. AF breaks down over time and forms acids, as well as the anti-corrosion additives being used up. Hence the recommendation for regular changes.

 

Aluminium engines today use OAT (Organic Acid Technology) anti-corrosion additives in their anti-freeze. Those anti-freezes work just as well in any engine. The myth about them attacking some gaskets seems to have arisen from a legal stoush in the '80s and '90s between GM and DEXCOOL over damage to manifold gaskets in Chevrolets being blamed on anti-freeze. GM lost the case. It was discussed a month or two ago on these fora. Here is a bit more information about it:

http://www.enginebuildermag.com/2010/07/closing-the-gap-on-intake-manifold-gaskets/