Plastic Thermostat Housings and Timing Chain Tensioners

[jkerouac@xxxxxxx]

Question:
Is it necessary to replace the plastic thermostat housing on the E36
with a later aluminum part?
    Have you had your's crack?
    Was it in a very cold or hot climate, or in severe running
conditions?
Also, is it necessary to replace the timing chain tensioner when R&R'ing
the cylinder head?
    Or is it np for a competent mechanic to reuse the old one?
    It looks the same as any older model BMW chain tensioner.

Thanks for your help.
'jk

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