525i M20 getting too hot after engine swap

[RoundLightsRule]

I just swapped my M20 from a wrecked '90 325is into my girls '90 525i. everything went as smoothly as can be when doing a motor swap in a dirt driveway. fired right up on the first try and idles perfectly. I never had any cooling issues with this motor in my e30 but it doesnt want to stay cool in the e34. I flushed the block and heater core with a garden hose before installing a new radiator. I filled everything up with water to try and flush the rest of the system but it just keeps getting hot realfast. i left it overnight and when i hopped in this morning, the coolant temp jumped right up to operating temp as as son as i turned the key 2 clicks. after sitting overnight? I have it parked on a hill to try to get the air to the front of the cooling system but it doesnt seem to be doing much. I dont have a pressure bleeder. any suggestions?

[madk0w]

Take the radiator cap off, Wrap your lips around the hole and blow. While you are blowing, crack the bleeder valves until just water comes out then shut them.

[StealthBimmer]

Take the radiator cap off, Wrap your lips around the hole and blow. While you are blowing, crack the bleeder valves until just water comes out then shut them.

:confused


Seems like maybe your temp sensor is shot? If you let the car sit overnight and the gauge was at operating temperature right when you started it, that leads me to believe something is not right.

There is no way the coolant stayed at 200 degrees overnight. My car cools down to cold after my 1.5hr class

[zubbie]

:confused


Seems like maybe your temp sensor is shot? If you let the car sit overnight and the gauge was at operating temperature right when you started it, that leads me to believe something is not right.

There is no way the coolant stayed at 200 degrees overnight. My car cools down to cold after my 1.5hr class

+1.. I don't know about M20's but perhaps the gauge sensor is different on an E34 than an E30. Anyhow I would change the gauge sensor first and then trouble shoot

[RoundLightsRule]

it was the temp sensor. the e30 has a 1 prong sens and the e34 has a 2 prong sensor. i wish i looked into that befor i put my lips on the rad cap... thanks guys.

[StealthBimmer]

i wish i looked into that befor i put my lips on the rad cap... thanks guys.

Cant believe you actually did that :rolleyes

[David325e]

Cant believe you actually did that :rolleyes

Ever bled an M20? Its basically a necessity.

[mtg729]

Ever bled an M20? Its basically a necessity.

I NEVER had to do that on my m20. Maybe I haz awesome coolant bleeding skillz :dunno

[David325e]

Hm, what did you have to bleed for? I never had to until I replaced the thermo and then it was the only way I could find to get coolant back through the lines to that bleed screw.

[RoundLightsRule]

Cant believe you actually did that :rolleyes
"Desperation is a stinky colgne" Super Troopers
You didnt have to listen to my girlfriend bitch all weekend about her car not being done. Now that im finished with the swap, its time for her to go to work...:embarrasm

[bustedbmw]

it was the temp sensor. the e30 has a 1 prong sens and the e34 has a 2 prong sensor. i wish i looked into that befor i put my lips on the rad cap... thanks guys.

Ohh its not that bad. Kinda sweet and tasty actually.....;)

[russiankid]

Cant believe you actually did that :rolleyes
It actually speeds up the bleeding process.

[StealthBimmer]

Hm, what did you have to bleed for? I never had to until I replaced the thermo and then it was the only way I could find to get coolant back through the lines to that bleed screw.

Pump the hose

[mikemxbike4]

I never had to put my lips to the radiator on my m20 lol.
It takes 20 seconds if you bleed it out propertly.