Doc Race Billet Coolant Overflow Tank

Torgus

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Nov 6, 2016
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My guess is making a rectangular coolant reservoir is not the issue. It is probably being able to sell it as a 'clean kit' that is the problem. I am guessing you need to extend the harness and potentially use some OEM BMW connectors they do not sell etc.

Then again their intake manifold requires the end user to hack up their OEM harness to extend it so maybe there is something else?
 
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R.G.

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Nov 17, 2016
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Is the stock plastic tank not strong enough?

I've had a stock one explode. I heard it happen as I walked in from the garage. Strangely, I knew exactly what it was when it happened.

24436
 
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JBacon335

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Nov 7, 2016
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Holy shit man, I would have never expected a full on separation like that. I'm happy I don't have the plastic tank anymore after seeing that
 

martymil

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I see it this way, better the plastic tank than something else which would get expensive, there must have been something wrong with your overflow for it to do that, either blocked or not working correctly.

Consider it a sacrificial part and much cheaper than a head gasket.
 

martymil

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The cap releases any excess pressure so it shouldn't do that that's what its there for and we have those temps here in Oz all the time
with no issues.
 

R.G.

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Nov 17, 2016
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The cap releases any excess pressure so it shouldn't do that that's what its there for and we have those temps here in Oz all the time
with no issues.

And if the gas escaping exceeds a certain threshold above the maximum volume allowed by cap?

24466




Edit: Keep in mind this is not uncommon in Vegas with these engines. I remember speaking to a tech prior to mine popping telling me he deals with a handful of them every summer.
 
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martymil

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drive normal for the last 5 min of your journey and stay of the boost and let it cool down and we have been hitting 115f on a daily basis here this summer

Do a pressure test on the cooling system just to check if you possibly don't have a cyl to water leak or might be getting a small head lift depending on how much boost your running.
 
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R.G.

Lieutenant
Nov 17, 2016
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drive normal for the last 5 min of your journey and stay of the boost and let it cool down and we have been hitting 115f on a daily basis here this summer

Do a pressure test on the cooling system just to check if you possibly don't have a cyl to water leak or might be getting a small head lift depending on how much boost your running.

This was ages ago and I knew it was from being an old plastic container. Tests stopped there at obvious conclusion but there may have been a 1-2% chance it was something other than that. Took the risk

Lol
Vegas 115 is a bit different then Aussie 115 f

Zero water in the air and 2500 ft above sea level
 

rac

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Nov 14, 2016
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This was ages ago and I knew it was from being an old plastic container. Tests stopped there at obvious conclusion but there may have been a 1-2% chance it was something other than that. Took the risk

Lol
Vegas 115 is a bit different then Aussie 115 f

Zero water in the air and 2500 ft above sea level

I don't have the stock tank anymore but from memory the pressure relief on the cap was higher than typical on other cars. Still, BMW will have designed the relief to be way under the tank rating. So either the plastic weakened with time, the pressure relief isnt working properly / line blocked or both.
 

R.G.

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This isn't some rare occurrence out here. The first billet reservoir designed for the N54 was made by a company in Vegas. It's over 100 F at midnight in the summer. The area next to us is called DEATH valley. CIC head units also fail if you don't take precautions. In other words, it's hot as fuck and if you have just a tad too much fluid in the tank it will explode as soon as you cross city limits. Ok, maybe too far but yea.