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Overheating after head replacement!?

Discussion in 'DIY (Do-It-Yourself)' started by gkivoo, Feb 9, 2019.

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    Hey guys, so as the title states, I just did a cylinder head job on my ‘87 325i m20b25 and I’m slightly overheating in a very odd way. Can someone help me pin point what it could be?

    I’ll attach a video of what it does, but basically filled the coolant and though I didn’t properly fill it with the front raised and bleed screw open, i tried to bleed air from the system afterwards.

    Some symptoms of the car..

    Car blows hot air once it gets up to temp. When driving temp gauge goes one needle width’s from center to the cool side. After coming to an idle from driving the needle goes to 2-3 needle widths from the center to the hot side. It takes a long time for it to”creep” up to this point but doesn’t seem to “get hotter” than that. If I rev the motor the needle goes back to dead center but then creeps up again. If I drive it goes away but the other day it actually stayed hot even on the highway cruising in 5th gear.

    I have replaced the cylinder head with all new gaskets. Tested head with new internals. New fan clutch, new water pump, 80° thermostat, coolant flush and refill with BMW coolant, new coolant cap, all new ignition parts, new vacuum lines, new fuel injectors, and new V belts. Fan clutch is a Mahle-Behr, water pump and thermostat are OEM.

    Coolant level has not gone down in the past 12 hours and no visible leaks present.

    Any clues as to what this may be?

    [Here’s a short video of what it’s doing.](https://youtu.be/-D4tE0wtf30) Mind you the temp goes up as high as the first line to the right of the 12 o’clock position but doesn’t quite ever touch it.

    And of course while all this is happening my [vanity plate](https://m.imgur.com/a/8dYSRLI) comes in the mail...

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