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Hard Brake Pedal


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I'd check the hoses before suspecting the booster; they're pretty long-lived. 


The hose that connects the brake booster to the intake manifold is in two pieces--booster to check valve (long), and check valve to manifold (short).  Leaks are hard to detect because of the cloth covering--the rubber can crack underneath without your noticing so inspect carefully. 


The long hose wears where it's clipped to the OEM air cleaner can; check that spot even if you have an aftermarket air cleaner.  The short hose is always bent to one side, and is usually the one that fails first; replace it with the same hose from an E21 320i; it's moulded with a bend in it so won't be stressed. 


Don't forget to reinstall the check valve in the correct direction (marked by an arrow)




'69 Nevada sunroof-Wolfgang-bought new
'73 Sahara sunroof-Ludwig-since '78
'91 Brillantrot 318is sunroof-Georg Friederich 
Fiat Topolini (Benito & Luigi), Renault 4CVs (Anatole, Lucky Pierre, Brigette) & Kermit, the Bugeye Sprite

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Check your fluid level. If it's low, and you do not have fluid in your pedal box, it could be leaking into your booster. When your booster dies, or your hoses/check-valve to your booster do, you get hard brakes.

Yes, there WAS skin on my knuckles before I started the repair...

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