So I did a dumb thing. I replaced my thermostat, water pipe, I thought I did a bang-up job of it - I even ended up with no loose screws, or wrong connections. Amazing! Except the damn water pipe didn't go in all the way, and there's a drip-drip now that basically never stops. So I am going to take everything apart again, and re-seat the water pipe. Question, though: does anyone remember if the thermostat has to come off completely or can I just keep all the hoses attached and sort of separate it by an inch or so from the engine block, just enough to get the water pipe out? I can't remember how much clearance there was.

Also, should I dump all coolant before I start, or should I just let whatever comes out at that point leak out, and just top up with the same coolant once I'm done?

 

Update to my own question. Short answer: you have to dump coolant.

Longer answer:

1) You can't really get to the lower thermostat bolt without undoing a hose. I mean you probably can with some contortions, but it's just MUCH easier to remove it.
2) Once you undo that hose, coolant starts spraying everywhere.
3) You don't have enough clearance once you unscrew the thermostat to move it far enough away for the water pipe to come out. You need a good 1-2" of clearance, and the only way to do that is to move the thermostat away... which you can't, because the rear hoses are in the way. You need to undo at least one of the rear hoses, but likely both.
4) Once you undo those hoses, they start spraying coolant everywhere.
5) Once you detach the thermostat, it starts spraying coolant everywhere.
6) Once you're done swearing and cursing everything, you undo the bottom radiator hose, and coolant sprays everywhere, and you wish you had done this first and gotten it over with.

 

If you would have removed cap from overflow and drained the lower hose of the radiator, coolant would not shoot everywhere. But yeah only way to get to the water pipe is take the thermostat off.

 

I did remove the cap and depressurise - I was maybe a little bit too graphic with the “spraying everywhere” part - it was more like “pouring”, lol. But yep. No choice.

 

How to test if you have everything sealed up and all is good, take your power bleeder that you use for your brakes, clean it throughly, attach it to your overflow, and pressurize to 15 lbs with nothing in it, and let it sit. If no loss in pressure, proceed to fill. Can fill with water to chase leaks this way as well.

 

Whoa. I didn’t even think about that. Thanks!!

Would it work for filling up too, to avoid having to bleed? I literally JUST got my Motive, so it’s still clean of brake fluid etc.

 

To be honest you probably could but I used the method everyone else uses. Heat on full blast, and let the car get up to temp and use the stupid bleed screw. Then once you think you have it fill to full, I checked mine next morning and had to add just a little bit, so on hers I overfilled it just a little which ended up being just right. Have done my n14 and friends n18 this way no issues. Now that stupid plastic t on the n18, wtf were the thinking.

 

The last time I did it with that stupid screw, I’m pretty sure I stripped it - ran car with screw open until hot, but then, I guess, screwing it in while engine was running wasn’t the smartest idea as it never really tightened to the point where it stops rotating … just tightens and then slips again. I still left it and I don’t think it was leaking any coolant through it, but I really don’t want to touch the damn thing again :(

Did you tighten it while engine running / hot or did you release pressure in the system before screwing it in?

 

I wonder if I can bleed it by disconnecting one of the feeder hoses to the expansion tank? It broke anyway so I’m replacing it - so what if I plug the upper hole on the expansion tank and leave the upper hose disconnected, pressurise the system with some coolant in it, until it starts coming out of the upper hose, then connect the hose to the expansion tank and complete filling it … or something. Just trying to find a way of NOT using that stupid plastic screw.

 

https://www.ecstuning.com/b-genuine-mini-parts/vent-screw/11537559883/
https://www.outmotoring.com/vent-screw.html - replacement bleed screw. I did everything hot. Hell I thought my clubby was running a bit warm one day, 222-225 on water temps, but it was hot and humid that day, so after my drive home, I cracked the bleeder, and let it do it’s things for a little bit and tightened her back up, fill up next morning just to get the same results the next day. Now that it’s fall, 218-220 like normal. I can’t tell you on the n18 because she doesn’t watch stuff like I do. I had to prep 2 Mini’s at MSSD this year, heaven forbid instead of sleeping, you’d get up and make sure your own car was ready for the day, sorry salty rant over.

 

Also, you can call Aaron at outmotoring after 8am and he will definitely be able to help with those hoses and maybe any other parts you might need. He helped me out a lot when I had a mishap on the dragon back in April. Let’s just say I got to know our cooling system really well, new radiator, and aux water pump to get me home, then a week later the water pipe cracked in the water pump housing. So needless to say, 2 complete coolant flushes in less than a month just for my n14. Then I did the R60s with n18 in August prepping for MSSD, which I had to replace that stupid plastic t last day of MSSD so she could get home.

 

Hahaha. Nice. Good to know - noted. Yeah Outmotoring are good folks, here’s a free plug for them.