Turbo Boiling Water After Shutdown?!
 

Good afternoon people,

I'm finding my radiator cap is popping and pushing some water into the over flow tank after shutdown. Even after going cool down drive.

Turbo is a GTX2867R

Feed is from side of block.
Exit is to mixing manifold nipple.

You can feel the bubbling from the exit water pipe from the turbo.

The turbo is not clocked. (I read Garrett suggest 20 degrees angle to help thermal spihon)

On the back of this I fitted a 22-24lbs radiator cap to tackle this but it still does it. The cap also does not pull any water back in after it has cooled down. When removing the cap there is zero pressure just if anyone asks if it's still under pressure.

Few people have said don't worry about it. It's better to that the turbo at 0' rather than 20' due to oil flow.

Old photo showing how the pipes are.

https://cimg4.ibsrv.net/gimg/www.mia...3d117b2c31.jpg


Just wondering if anyone has any ideas or advise for me to try?

Thanks.

rotate the hose so it goes under the hot-ass-air intake

Thank you.
I guess it would make sense. If it still does the same. Any other suggestion. Just want a collection of ideas if it comes to it.

pressure test your cooling system - something's not right if it's not fully pressurized after shutdown.

I did a few months back.. Have a slight hiss noise from the water feed pipe when it goes into the AN fitting connector.. Possible? it's sucking in air.

I just pushed it with my hand and it stopped. no drips or nothing just a ever so slight hiss.

Can you tighten it just a little more.

Going to remove and redo the fitting. It's the AN fittings you slide the pipe on then tighten up.

is it a compression fitting?

​​​​​​​Well then that sucks.

AN -6 (AN6 JIC -6 AN 06) 90 Degree ULTRAFLOW Swivel Seal Hose Fitting In BLACK | eBay

^^ this is what I used.

Oh yea those. I either use the Aeroquip socketless or go to a hydraulics shop to crimp on ends. Hopefully its a pretty easy fix, but you definitely want to have that coolant system buttoned down tight.

I am right in saying that.

If I have a coolant leak.. even if it does not leak (enough for air). It will effect the boiling temperature which could be the cause of why after shut down the turbo boils the water as it isn't pressurised as it should be. But is fine during normal use.

A liquid boils at a temperature at which its vapor pressure is equal to the pressure of the gas above it. The lower the pressure of a gas above a liquid, the lower the temperature at which the liquid will boil.

I wouldn't say it was fine, normal use includes shutting down.

any leak in the cooling system is a bad leak. a pinhole can and will cause boiling which can lead to overheating and an early engine death.

Thanks for the advise people.

Can pulls fine gets to about 88-89c after loads of hard pulls all the way to 6th gear 6500rpm.

It's only on shut down even after cool down drive that it bubbles. You can hear the turbo gargling away then hear what sounds like bubbles pulsing up the water line exit of the turbo.

Maybe replace the radiator cap? :dunno:

Already done that. Fitted a Stant 22-24lbs cap and still does the same.

Little update.

Will be rerouting the line to go under see if that makes any different.

I have also ordered a relay timer. Which I will hook up directly to the fans off the battery / fuse box 12v to be used with a push bottom to activate it.

This will allow the fans to be on for x amount of time. Will do 3mins and see how I go. When the car is off.

Almost like a turbo timer but only for the fans.


I'm hoping the effect of the fans on it may just stop the turbo boiling the water causing steam and building the pressure to make the CAP pop.

Can you look in the phone book and find a local hydraulic shop. Then have them make you a new line and see if it still makes the noise. If you can push the line around and get the hissing to stop, then I would be looking to replace the line.

Cliffnotes for those just entering this thread:

"Hi my coolant bubbles because pressure isn't being kept in my cooling system. I've done everything. What should I do?"

Did you pressure test?

"Yes, I have a leak. I'll do something else that doesn't address sealing any pressure loss, but I wonder what it could be."

[...]

It only hissed once. Every time I have checked it's been fine. Will be refitting the fittings to make sure all is okay.


Funny man :P

It doesn't leak. But I am going to check it and change.




Update.

I've been advised by a few soruces to clock the chra 15 - 20 degrees and there is a pocket where if the chra is flat it wouldn't siphon out and just boil. clocking the turbo slightly promote the hot water to move upstream.

They have also advised run the exit water feed directly to the raditor. Top right. They said this has been proved to be the best way but isn't aways possible depending on the setup.

Are you using any wetting agents in the coolant ?

Routing it to the radiator will help shed heat before being pulled into the pump again. I'll be doing the same thing when I revamp my coolant stuff.

Running your radiator fans after engine shutoff is only going to accomplish one thing: reducing the life of your battery.

Seriously - pressure test your cooling system and make repairs until it can reliably hold 20 psi...

Then put a 14-16 PSI cap on the radiator and be done with it.

Everything else you're doing is a waste of time, effort, money.

Clocking the turbo isn't going to do jack shit for you - taking the high point out of your water line will marginally help, but won't fix your post shut-down complaints.

For the record, no matter what you do, you're going to be able to audibly detect at least some heat-related post-shutdown activity going on in the CHRA; even if you idle for 10 minutes before shutting it down...unless you put a fan timer on your shit, in which case the fans are going to cover the sounds of said activity while cooling the coolant in the radiator and doing nothing to cool the coolant in the turbocharger. The only "clocking" you should be doing to the turbocharger is ensuring that the oil supply line is as close to "up" as possible; which looks to be in the exact orientation that FM shipped it to you.

No, you didn't already do that. You replaced it with a cap of a different spec, which is only going to make this harder. Put OE spec cap back on.

$20 says both radiator caps are bad

Problem solved!! Good work OP on coming up with an innovative solution to a complex situation!


lol

https://cimg5.ibsrv.net/gimg/www.mia...d8bce9be53.jpg
https://cimg7.ibsrv.net/gimg/www.mia...c464275446.jpg
https://cimg8.ibsrv.net/gimg/www.mia...07e471bd37.jpg
https://cimg9.ibsrv.net/gimg/www.mia...3554878e6f.jpg
https://cimg0.ibsrv.net/gimg/www.mia...4eb0526cc2.jpg
https://cimg1.ibsrv.net/gimg/www.mia...c46b1387b5.jpg
Little update.

went to another extreme which solved the problem but also created another one.

I spoke to owen devlopments a turbo company here in the UK.

they said to clock the turbo or.. do the turbo return directly to the radiator which they said is the setup they alway do if possible.

so got the mixing manifold welding up and changed abit to suit my setup better and got a 8mm barb welded onto the top right of the radiator.

lovely I thought so fitted it all back up and low and behold it works perfectly and you can hear the water being pulled through on shut off and no cap popping problem.

but guess f**king what... the car cruises at 65c and won't get up to temperature.

Bastard!!! So the fact I have bypassed the mixing manifold that 8mm hole is basically the same as drilling your thermostat with a 8mm hole.

Bloody great..

so im back to square one wishing I just tried the fan mod first. Which may or may not of solved the problem anyway.

FML!!


so do I cover some of the radiator during the winter months. (It's winter here 5-10c and will get lower)

or drill out the mixing manifold and clock the turbo and fit it back to normal?

Well, since you've done such a good job of listening to us so far and implementing our suggestions vice inventing your own, let me take 5 minutes of my own time to talk you through everything you need to know in order to solve this issue....

:eggplant:

The only suggestion really..

Was to route the pipe under the turbo not over.

But as I had been advised to go direct to the radiator by a known turbo specialist I thought I try that.

But it would seem 8mm flow of water is enough to cool our engines by 20c.

so I am going to route the pipe under and see what happens and update. as per this thread suggested idea.

No fucking shit the car won't get up to temperature. The only thing that should ever meter water to the radiator on a street car is the thermostat. If you do it any other way the thermostat is pointless.

Whoever told you to do that is an idiot. Cap it off and go back to how you had it. Fix the air leak.

You are always going to boil coolant if there is an air leak. It won't boil, or you won't notice it boil, while it's running because it's constantly replacing the lost pressure.

Fans aren't going to do anything.

Did you fix the leak?

I re-did all the fittings on the water feed to make sure there were okay.

Did you test it the right way before you disabled the thermostat?

I rechecked all the lines and refitted them to make sure all was okay.

tested the car, same problem.

Then got bits welded on. Which fixed the problem and you could hear the water correctly shiponing on the turbo.

But this was with the thermostat technically disabled.


im now going to do as suggested here and run pipe underneath if it does the same again I will clock the turbo and hope for the best!