s50 will not bleed

[catalyst.]

I just installed an s50 in my e36 and the coolant will not bleed, ive jammed as much coolant in it as i can and it just overheats. Never had a problem bleeding these things before that i can remember. This engine was on a stand and was completely empty of fluids when i built it up.

The front of the car is elevated
Using BMW coolant
Massaging the radiator hoses as i do it

The upper radiator hose goes airbound EVERY time

Could it be a bad thermostat? i took the thermostat off of my m50 it has around 30k miles on it, looked brand new

Starting to be afraid im going to blow a f*cking headgasket here, i shut down when/before it hits the 3/4 mark everytime

[jalopi]

Is the fan not coming on?

Also, you might wanna try drilling a very, very small hole at the edge of the thermostat, then install it again with the hole pointing up. Guaranteed no airlock at the thermostat then

[catalyst.]

i have the engine driven clutch fan on it, and the ac condenser is removed. I havent noticed if the electric fan comes on or not but honestly i dont think it matters, i had no clutch fan on my m50 for 5 years with no issue at all ever summer or winter.

I put it on the s50 just for good measure.

I think i might try removing the thermostat all together and see if it will at least bleed/not over heat like that?

i bought a new t stat at autozone so tomorrow i will go at it again.

I just hope i dont have to buy anymore coolant....... so freaking expensive

[golde30]

well your first problem is you reused an old Tstat... second, autozone parts. And yes, BMW coolant is pricey, but the best.

[catalyst.]

No reason to replace something that is working and low mileage it came off my running m50, the autozone t stat is for quick replacement if the one in there tests bad. Sorry i dont feel like waiting until tuesday for UPS to show up with a new 'high end' t stat

Its almost like the t stat is airbound itself, doesnt have enough contact with hot coolant to open, is that even possible?

[E30Gus]

Drill the hole like Jalopi said. It makes bleeding a "hole" lot easier.

[jalopi]

Biggest hole I'd do is 1/8th inch if that's the smallest you have. Definitely not bigger, but definitely smaller. Doesn't have to be a big hole to let the air through. Get as close to the edge of the gasket as possible. Also, make sure you installed the t-stat the right way (as in not backwards). Did that myself a few times when tired :D

[catalyst.]

lol yeah man ive done it too, i took a pic with my phone this time when i installed it so i wouldnt forget it if i installed it right hahaha

i have all size drill bits but the t stat i picked up from autozone (motorrad germany) already has a hole in it its about an 1/8 in the large part of the t stat. Although i am probably going to go by autopart intl and pick up a new t stat housing gasket because the one that was in there has RTV stuck all over it and the rtv will not come off :( So i may pick up a new whalen t stat when im there and return the autozone one

[325isdan]

Did you remember to put the temp to hot and turn on the fan?

Sent from my C5306 using Tapatalk

[catalyst.]

yeah

[catalyst.]

Ok new thermostat in with bleed hole, with new oring, and new gasket, waiting for the RTV to set up for an hour or so. With any luck car will be running by 4 pm!!!! Wish me luck

[jalopi]

Sweet. Oh yeah, put your heater on full blast if you didn't do that, gotta get the heater core valve opened up.

[catalyst.]

Still overheats, so pissed. Upper rad hose is still full of fucking air

whats next leak down? pressure test coolant system? :(

[catalyst.]

Is there any chance having the TB heating sensor plumbed backwards would cause anything like this, i highly doubt it but im just trying to think of things i may have screwed up during install

[FredK]

I had a 75 or 80 degree thermostat installed in there, that already had a hole drilled in it, so it's weird that it never opened to allow coolant to flow into the radiator. I had that TB thermostat deleted, but it shouldn't matter. The water pump was new when I installed the engine, and it was a genuine BMW pump. The thermostat does have to contact fluid to get it to crack open, so you do have to get some coolant touching it.

On an E36 I usually would slowly fill the system, completely remove the bleed plug and radiator cap from the expansion tank, and do a medium rev to around 3000 rpm and hold it until I saw water spewing from the expansion tank vent. Then I'd close the vent and watch the stream of water into the tank until it was mostly bubble free, then allow the car to cool.

Let me know how things go.