Intermittent Temp gauge + bleeding issue

[lolcantturn]

Swapped a S50 into my car paired with a M42 radiator. My temp gauge worked before the swap just fine. Got the engine going and it looked like the gauge wasn't moving even though the car was getting plenty hot. Swapped out temp sensors (even though I had an E30 temp sensor in there to begin with), and it began to work.
I tried to bleed my coolant to no avail because I ran out of time. Let the car sit overnight and then I tried to bleed my coolant again but my temp gauge wasn't working again! I checked that I had continuity from the sensor plug all the way to C101 so it's not my wiring harness. Could there be an air bubble so big that it's preventing my temp gauge from working? I have been having bleeding issues after all.

Yes I've smacked the dash ;)

[iwantspeed]

Raise the front of the car super high up.

Have the heater on full blast


You can buy an infrared gun and point it at the radiator and see where it's at.

[mtech325]

Another trick that seems to help with the m42/e36 radiator expansion tank is to fill the radiator first from the top hose, then continue to add more fluid to the tank. I've had good luck trying to bleed the cooling system this way, since the fill tank sits a good bit lower than the m20's setup.

[lolcantturn]

Another trick that seems to help with the m42/e36 radiator expansion tank is to fill the radiator first from the top hose, then continue to add more fluid to the tank. I've had good luck trying to bleed the cooling system this way, since the fill tank sits a good bit lower than the m20's setup.

No such luck this way.

I'm wondering what it could be, it's a certain air pocket.

I don't have any heat anymore, and I can't get the vents to blast out remotely warm air even when giving it high revs at operating temp.

Both radiator hoses are hot and feel like they have water pumping through them.

I shut the engine off when the radiator reaches 208*F via temperature gun.

Could my thermostat be stuck closed? Zero heat and both radiator hoses get very hot.

Currently on my 5th day of bleeding this thing

[lolcantturn]

Both my inlet and outlet heater hoses are hot but still don't have heat.

[Sh3rpak!ng]

are you 100% sure you don't have the heater hoses backwards?

[lolcantturn]

are you 100% sure you don't have the heater hoses backwards?

Spider hose on top, cylinder head hose on bottom

[lolcantturn]

Heater valve failed, making it impossible to bleed.