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white smoke + rough start + coolant smell = cracked rotor housing?

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Old 12-21-2009, 08:26 AM
  #26  
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Regardless of what the dealer may tell you...................go ahead and call Mazda North America and see what they might do. It's worth a shot! Good Luck!
Old 12-21-2009, 06:28 PM
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Well I called both the dealership and followed Mazurfer's advice and called the North America office with no luck =(. According to the north america office my vin has been 2008'd which means salvage and void warranty as suspected. Hmm now i just need to find somebody else with a 2005 shinka to copy theirs and forge my vin i kid.


Originally Posted by SARRAS
"The froth on the dipstick tastes like coolant."

Okay well that's my Bind Moggled for the day right there....
Hehe that froth when it has some coolant in it makes for good topping on pies due to all the sugar. Nah It's one of the many things I've learned so far from this little event. My froth did not smell like coolant in any way but it definitely had a slightly sweet taste and I was shown the color differences in what they should be.
Old 01-01-2011, 01:37 PM
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Thanks for the detalied post and reponses. My 145k mile 04' just started doing the exact same thing and I've been haunted by the idea of an internal coolant leak now for a few weeks. It still runs nice and smooth all the way to red line once it's up and going. Getting it started though is a bear. crank crank crank crank.... crank crank crank crank... crank crank burp chug chug... and then the white cloud that smells like antifreeze.

The steam/smoke goes away after a minute, but the ominous sweet smell of coolant persists. It is most notable when stopped or backing up with the windows down or vent fan on.
Old 01-01-2011, 07:34 PM
  #29  
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The reason it runs rough for a few minutes is that coolant wets the spark plug in the affected chamber and keeps it from firing for a little while...so that chamber is not producing any power, and the engine runs like a 6 cyl with only 3cyl firing. After a couple of minutes the plug heats up enough to burn off the coolant and begins firing again, and the engine runs normally.

During this time, the puddled coolant in the affected chamber is being blown out the exhaust by compression pressures, and this exhaust is also hot because of the other chamber which is firing normally...so you get all your steam out the exhaust.

The misfire code is due to the PCM picking up the variations in e-shaft movement, since there truly are misfires due to the wet plug.
Old 01-01-2011, 08:45 PM
  #30  
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Here's some pics of the last coolant seal failure renesis I did. 107k on an 04 MT.

Coolant in the cat when I took it off...a lot more already poured out of the front flange when I loosened it up.



Guess which plugs were from the coolant seal failed chamber?



I don't think coolant is supposed to come from there.



Here's a burned section of coolant seal. Carbon deposits indicate blowby has breached the seal. It's supposed to be thick, orange and pliable like the rest.



Another bad section.

Old 01-01-2011, 09:00 PM
  #31  
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Another blown out section of seal.



Rotor from the affected chamber.



What I felt was the main failure point.



Another failed point on the seal. Notice these failures are worst in the hotter areas of the engine...exhaust port and spark plug hole area.



As it turned out the rotor housings had significant cracks extending from the leading and trailing plug holes at the chrome liner. Technically these could have been reused to make a running engine, but compression and longevity would have suffered so the owner opted for new rotor housings. I see a LOT of cracking on the renesis rotor housings, any engine over about 60-70k can start to see a lot of cracking and for that reason alone it is a good idea to replace them if budget allows for the $1500 replacement cost. Note that these cracks have NOTHING TO DO with the actual coolant seal failure or coolant leakage, and are simply a result of high local temperatures from the spark plugs.

In a renesis all the major parts from a coolant seal failure engine should be reusable (save for the rotor housings, pending inspection for cracks) unless the engine is run severely hot enough to warp components, or unless the coolant is allowed to sit inside the chamber(s) for more than a week or 2. I've torn down a few renesis cores that got coolant/water inside them and were left to sit for a little while (a few weeks or a few months) and found that the iron housings get EATEN UP by the smallest amount of water left inside. Also the rotors will pit and the rotor seals will rust and lock in place.

It's very important that if you have a coolant seal failure in a rotary, you know a few things. 1) if you keep driving it, it will continue to advance. You will begin to lose coolant very quickly, as the seal degrades it lets compression pressure push coolant out of the engine via the overflow. Vice versa, when the engine is stopped and there is no more compression pressure, the coolant (still hot and pressurized) blows past the same seal into the combustion chamber and lets coolant puddle up inside the chamber(s). Thus you get the wetting of the spark plugs, hard starting, and steam on startup.

As this condition advances you'll lose coolant so quickly that the engine will begin to overheat after a short time, because coolant is being replaced with air from combustion. Once it reaches this point it's time to stop driving it, or you can do damage by warping or cracking components.

ONCE YOU STOP DRIVING IT, it's imperative that you follow these steps to preserve the internals for future rebuilding:

1) drain coolant from radiator

2) drain coolant from block (driver side just above oil pan)

3) start engine and run for 30-45 seconds, enough to clear out any coolant in the combustion chambers. No, running it for this short a time without coolant will not damage any internals.

4) via either the intake manifold or lower sparkplug holes, inject a generous amount of oil to displace any residual coolant/water, prevent rust, and lubricate the seals until it can be torn down. You can use thin motor oil such as 5-20, ATF, 2 cycle oil, etc. Pump some in, turn the engine a little by hand or by bumping the starter, pump in some more. Maybe a cup or two per chamber is good. Replace spark plugs (if removed) and rotate the engine several times to coat everything inside. It's not a bad idea to repeat the rotating process every few weeks to keep the internals coated (the oil drains down and off of the parts over time).
Old 01-01-2011, 10:01 PM
  #32  
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Good tips from RR once again.

Surprisingly, the coolant passages on that engine look clean. Which leads me to believed the coolant didn't go bad in that engine rather just bad luck?

Also, People dont ever use the block seal/ head gasket repair ****. It wont work and ive personally seen and had to clean coolant passages in housings clogged with that stuff.
Old 01-01-2011, 10:11 PM
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Coolant pH turns acidic over time and can eat into the seals, so it's a good idea to change the coolant every 3 years or so even if it looks fine (it will). Mostly though it is the areas of highest constant local heat in the engine where the seals fail.
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