[P38] Exhaust gases in coolant

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Once it’s warmed up and the thermostat is opened, I rev it with the cap on. If you rev it hard with the cap off you’ll get coolant everywhere. I find it shoves any air out that way. A few blips of the throttle should force coolant through all the pipework. You don’t need to go mad.
 
I believe I followed the RAVE method:

- Drained as much as I could via rad plug
- Slowly filled expansion tank with a hose on a small stream
- Started engine, monitored level, waited for thermo to open
- Stopped engine, waited for it to cool, topped up expansion tank again.

I believe that's how it's done it RAVE? Maybe without the garden hose.

Oh and I also blew through the return pipe to clear it
 
blue_cheese said:
I believe I followed the RAVE method:

- Drained as much as I could via rad plug
- Slowly filled expansion tank with a hose on a small stream
- Started engine, monitored level, waited for thermo to open
- Stopped engine, waited for it to cool, topped up expansion tank again.

I believe that's how it's done it RAVE? Maybe without the garden hose.

Oh and I also blew through the return pipe to clear it
Click to expand...
RAVE assumes you drained the system previously. You seem to have missed 12 & 13 in the procedure ? Personally I have an issue with step 17-18. Step-17a should be to top up the system while the thermostat is still open !!

Also during step-15, that's when you also need to keep squeezing hoses to burp the system whilst filling.

Another trick is to use a vacuum pump on the radiator bleed hose whilst filling. That way the coolant tends to fill all the cavities inside the engine better with less airlocks.

1746176152127.png
 
Just had another go.

I taped the end of my hoover up and created a makeshift slot for the rad bleed pipe:
20250502_135608.jpg

And after I filled up to the neck of the bottle, I stuck the hoover on for a few seconds.
The level in the expansion bottle quickly dropped, so I topped it up to the neck again.
Hoover again for a few seconds, and same happened again, so I topped up until water starting coming out of the bleed pipe.

I then did steps 15-19 as normal (including burping).

Currently letting it cool - I'm waiting for one of you to tell me why this isn't going to work and why using the hoover to get the air out is a bad idea 😆
 
Just been for a 10 minute drive.

Temps idling between 90-91, max 92.
20250502_153222.jpg20250502_153231.jpg

I'll keep an eye on the levels and for any leaks.

Only thing that concerns me - assuming the OBD tool is correct - what kind of damage could have occured if the temps were actually at 118ish?
 
blue_cheese said:
Just been for a 10 minute drive.

Temps idling between 90-91, max 92.
View attachment 340214View attachment 340213

I'll keep an eye on the levels and for any leaks.

Only thing that concerns me - assuming the OBD tool is correct - what kind of damage could have occured if the temps were actually at 118ish?
Click to expand...
Yeah if you didnt put the engine under load and the cap hadnt vented coolant yet i dont think you would have done damage.

If you just idling your cylinder temps wont be very much above coolant temps. But on the other hand if you have 118deg coolant temp but you at 50% engine load your cylinder temps will be extremely high and thats what warps heads.
 
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