Mk4 GTI, Did i just poach my engine

[elcono]

Afternoon

So it seems my coolant flush last week wasn't as successful as I thought so I went out and grabbed some G13 and started again due to green discolouration in the coolant. (im guessing pockets of the prior fluid weren't G13 and were stuck somewhere)

I opened the drain valve whilst the car was running and stuck the hosepipe in the coolant bottle. I let it run for about 10 minutes to flush everything out but the flow rate out the drain valve was crazy slow (you could drink through a childs straw faster)

After about 12 minutes the coolant in the res started steaming and a few large bubbles came up. I don't know if this was where the water was starting to boil, or if air pockets were starting to dislodge? anyway I put my finger in it and it was pretty hot, hot enough for me to shout 4 letter short words beginning with C

I turned the car off to let it cool down and continued running the water through as I didn't want anything to stay hotter than it needed to be. Next I wanted to see if anything was making it past the drain valve so I removed the lower radiator hose and a massive surge of green coolant came out

I started the car with the lower hose disconnected, water still flowing through with the hose, and it flowed through until clear without issue with the drain valve shut

I then filled it up with G13 coolant 50/50 let the ar run for 20 minutes and the temperature it bang on the middle

So is there anything I should be checking? The only thing I can think of is.....

This green **** blocked something that became dislodged when I removed the lower radiator hose (seemed to have a bit pressure built up)?

Something else is affecting the flow rate/lack of pumping power? this is a bit out of my scope but if someone can point me in the right direction

Lastly how hot should coolant get? after 20 minutes of idling should you see a bit of steam? is this normal?

I might be worrying about nothing, but when I saw those large bubbles come up in the coolant bottle I thought I better play itself

Thanks again in advance fellas

[h100vw]

Personally, to heat the engine up, I'd always drive it. Even if it's just around the block.

It's does sound like maybe the green crap reacted with the G13 and it curdled. The way I do a flush is to fill with water, drive, drain. Fill, drive, drain and repeat until the water stays pretty clean.

Also, if you drain it all, there will be air in the system, heater matrix etc which won't move until the stat opens up.

I don't think you'll have done any damage. Just watch it the next couple of times you drive it to be sure. Carry 3 or 4 litres of water with you too.

Gavin

[sports racer]

If your temp gauge doesn't go past normal you haven't done any damage. Steam is normal, just make sure the fan is working and the radiator is full so it doesn't overheat.

[elcono]

have either of you had to remove the lower hose to drain? or seen a really bad flow rate on the drain valve?

Also at the top of the coolant bottle/blob, there is a return that come back to it. What inbound flow rate should this be? mine was trickling back, if this is excess/return coolant, where does it come from

Also how bloody hot does it need to get for the radiator fans to come on? is there anyway to make them come on?

As always its appreciated, one day this car will hopefully make it to the track!

Cheers

[h100vw]

Did you have the cap off the filler? It doesn't gush out unless the system is under pressure. The return only flows hard when the revs are up, as the water pump spins with relation to the engine speed. Gun it with the cap off, it spray all over.

Gavin