E24: Overhauling the intake manifold on an M635csi

This article shows how to overhaul the intake manifold on an e24 M635csi. This may be needed in case the o-rings and rubber sleeves (parts #8 and #5 in the picture) show signs of wear, or if your accumulator needs inspection (rough idling, because of additional air being sucked in through a crack....) or if you simply want to clean the intake necks.

Actually I overhauled the complete intake including throttle bodies, idle control valve and part of the cooling circuit, so the pictures will not always show an accurate situation. This post should be read in conjunction with:
 xxx which shows the adjustment of the throttle valves.
yyy


Abbreviations:
AFM = Air Flow Meter


Start by loosening the hoseclamps on the rubber sleeve between the AFM and Accumulator. It's sufficient to loosen only the clamp on AFM side.


The only way to remove the air accumulator is by unscrewing the 6 intake necks from the throttle houses. There is no point in attempting to remove the rubber sleeves by loosening the hose clamps, since the intake necks extend an inch into the accumulator.


To loosen the nut nearest to the firewall (cilinder #6) you'll have to use an angled joint on the socket.

Reacties

  1. mirass108 juli, 2019

    Hello,
    Could you please help me with the hose from inlet manifold? Where this hose (no.15 on the first figure) is connected to?

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