So every 2.0 tdi is at risk with the shorter 77 mm hex key so I wanted to find out if VAG addressed the balancer shaft keyway when they went to the longer 100mm as used in later common rail engines.
So I had a conversation with
KMB Parts Direct 07526 251 559.
He claims the original balancer shaft does have a hexagonal bore which contradicts an Audi Driver magazine feature on the 2.0 tdi twin balancer shaft oil pump saying it's 6 tiny machined grooves so just the shoulders of the hex key are driven .
KMB Parts Direct
Wear occurs with vibration etc coming off the throttle , it's a poor fit because wether it's a 100 mm or 77 mm key they both go into the balancer shaft end 40 mm , but because the first 25 mm part of it is a 9mm bore the hex key is 6mm it means just 15 mm of the key is driven .
Measured dad's old 77 mm key , yep 15 mm is shiny and worn.
So a remanufactured balancer shaft will have a 10x harder chrome vanadium hexagonal keyway insert with 40 mm of contact
ALL unaddressed 2.0 TDI's will fail at some point .
He's not against VAG either , he drives a Audi A4 B7 3.0 TDI
Either theory can end in disaster just wondered who was right ?
Hexagonal keyway bore or 6 tiny machined grooves ?
"instead of being a matching hexagonal hole , as is the case with the oil pump itself , is a bore with tiny machined grooves which drive the very tips of the 6mm hexagonal shaft "
Audi Driver magazine
So I had a conversation with
KMB Parts Direct 07526 251 559.
He claims the original balancer shaft does have a hexagonal bore which contradicts an Audi Driver magazine feature on the 2.0 tdi twin balancer shaft oil pump saying it's 6 tiny machined grooves so just the shoulders of the hex key are driven .
KMB Parts Direct
Wear occurs with vibration etc coming off the throttle , it's a poor fit because wether it's a 100 mm or 77 mm key they both go into the balancer shaft end 40 mm , but because the first 25 mm part of it is a 9mm bore the hex key is 6mm it means just 15 mm of the key is driven .
Measured dad's old 77 mm key , yep 15 mm is shiny and worn.
So a remanufactured balancer shaft will have a 10x harder chrome vanadium hexagonal keyway insert with 40 mm of contact
ALL unaddressed 2.0 TDI's will fail at some point .
He's not against VAG either , he drives a Audi A4 B7 3.0 TDI
Either theory can end in disaster just wondered who was right ?
Hexagonal keyway bore or 6 tiny machined grooves ?
"instead of being a matching hexagonal hole , as is the case with the oil pump itself , is a bore with tiny machined grooves which drive the very tips of the 6mm hexagonal shaft "
Audi Driver magazine
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