M44 loud rattle on startup

[Hellrotruss]

My M44 has developed a loud rattle on startup that disappears after 5 seconds or so. It almost sounds like it could be coming from the inlet manifold area? Or underneath. Revs fine and drives as normal after that initial startup. Ideas?

 

[Antm72]

It sounds like the oil is draining out of the hydraulic lifters and once you have oil pressure normal service resumes.
When did it last get a service ? It may help..

 

[Hellrotruss]

The car had its last oil change 4K ago and it's been serviced religiously. Its not coming from around the cam area it's more on the right hand side. I wounded es wether the starter motor solenoid is getting lazy and isn't disengaging fast enough.

 

[Hellrotruss]

It doesn't sound engine related to me.

 

[Tracy Dee]

Could be noisy Disa valve if not lifters.

 

[colb]

Noise from the inlet manifold may well be down to a Disa or adjuster valve unit as BMW call it making a clacking noise, they have been known to fall apart and bits get sucked into the engine. Only about two bolts at the end of the intake and it can be pulled out to check it's condition wiring connection at the bottom of the unit. I had to replace mine when it started making a clacking noise. It's not cheap.
http://www.realoem.com/bmw/enUS/showparts?id=CH72-EUR-08-1998-Z3-BMW-Z3_19&diagId=11_1569
Item number 6 in the diagram.

 

[Hellrotruss]

Just for the reference of anyone who experiences this problem in the future it was the starter. And you can replace it without removing the inlet on the m44 relatively easily. Starter gear had gone blue and burnished from getting super hot!