Burning Coolant and Deposits Color
 

Hi All,

I have been searching about the color that coolant’s deposits leave at the spark plugs, engine chambers and general inside the engine.

I came to the conclusion after some searching in the forum that burnt coolant leaves some whitish deposits on the plugs and also engine.

I have read carefully the rotary resurrection thread about the renesis teardown that was burning coolant and I have noticed several whitish marks on certain parts of the engine.

So my question is kind of chemical/technical field:

Why coolant for example FL22 that has a intense green color , when it is burned inside the engine (i.e due to some rubber seal failure ) leaves whitish marks/deposits? Why not leaving Green mark/deposits ? How do you explain this ?

Thanks

if your engine is "drinking" coolant, you'll get bad ass idle and ULTRA lack of power. After a while, with enough coolant inside the chamber(s), Your engine will not even start.

if you really think your engine is drinking coolant, check it at dealership, you should be covered under engine warranty.

green is just the chemical's color. Most chemical when burned, will leave white marks, and those are the "deposits" that cannot be burned.

Same thing for pretty much everything. Like human body, when burned to a "level", you will be left with just white shinny ash ... and you stick those into the Urn :)

Yes I support your opinion and you are wright.

However, I have heard that you may leak only some drops of coolant into the chambers due to failed rubber seal and this leak stops when the engine metals expand due to heat. So after expansion you have no leakage and the prior leakage is not so serious as to cause misfires or the white smoke produced is for some seconds only.

What do you think about that ? Is it possible to leak only some drops of coolant inside the chamber and having no sign of this leakage ?

I am asking this because I have noticed to many RX-8 owners some green deposits on the spark plugs and I suspect that this is coolant. On the other hand, I have read also that burnt coolant leaves whitish marks and not green although the FL22 has a green color.

It could be.

Just because the substance is green doesnt mean it will be green after burned.

if you see it around spark plug holes, maybe take the plugs out when its cold? see if u see any "fresh" coolant coming out ? or any water spot on the plugs itself ? cuz water never mix with oil/gas and if its leaking inside, you should be able to see something on the plug itself.

Yes I have done this. Cold engine and change the plugs. No sign of coolant. However, I cannot still render and a satisfactory explanation to the green deposits on the spark plugs.

I have also read that a spark plug that has an Aluminum overlay on the electrode under some circumstances and specifically extreme heat can leave some green deposits.

check those plugs with clearly visible green marks. Some people claim that the green marks is not coolant because burnt coolant leaves white marks. As a result the only chemical explanation for the green color is high temps

http://www.imageshack.gr/view.php?fi...8dh8uuc4nc.jpg

I see a white film on rotor housing coolant passages that did not overheat and did not have a coolant seal failure. Have you ever had a leaking coolant cap or hose, or otherwise spilled coolant on hot aluminum repeatedly before? Such a leak or spill will leave a white residue/trail.

I do not know WHY this is, I just know that it is. When aluminum is very hot and it contacts coolant for a long period of time, a thin white residue forms. This can also be seen in aluminum piston engine heads.

Of course there are other colors sometimes deposited too...for example rusty coolant (or straight water instead of coolant) leaves brown deposits.

I have probably 60 or 70 rotor housings on my shelf and they all have some sort of residue in the coolant passages.

That is probably unburnt coolant. That's why it is green.

So you believe that coolant can remain at the tip of the spark plug for thousand of miles without being burnt

how come when you poop its almost always brown? Ive been eating all kinds of colorful things trying to change my poop to a bright orange or blue... not working :icon_no2:

Have you tried eating lots of black licorice :) ? Report back after you do.

Beets are great for that ;)