6Q0407621BR/6RD407621/6RD407621A is the Ref No. of camshaft bearing bush,The detailed information is as follows:
Name:camshaft bearing bush/10 pieces per set
Ref No.: 6Q0407621BR/6RD407621/6RD407621A
Applicable models of 6Q0407621BR/6RD407621/6RD407621A
Skoda: FAB00-01;04-10/COT01-13/RO06-
VW: JE06-08
Seat: ALT11-13/IB09-11/LE06-10;11-13/TO 99-09
Audi: A2 00-05/A3 01-13/A4 99-08/A6 98-09
How to determine if the gap of a camshaft bearing bush is too large?
The main purpose of a camshaft bearing bush is providing friction protection during high-speed movement of the connecting rod or crankshaft. Bearing burning and seizure accidents are not uncommon during use of engines. Most of such accidents result from improper installation of the bearing bush that leads to damage to the lubricant film between the journal and the bearing bush and consequent friction between the bearing bush and crankshaft. Under high-temperature, high-pressure, and high RPM conditions, the wear-resistant alloy layer on the bearing bush can wear or melt prematurely, peel off, and stick to the journal, thus causing mechanical burning and seizure of the bearing.
In order to determine if the gap of the camshaft bearing bush is too large, a stethoscope may be used to contact the upper part of the crankcase. In the case of an excessive gap, while the RPM increases, the sound will grow louder than the common sound of the camshaft bearing bush. Abnormal sound may also be heard after opening the fuel filler lid and knocking on corresponding part. In serious cases, the sound can even be heard next to the engine.
Spacer shims can be added to the bearing bush seat to correct an excessive gap. In the case of excessive lateral gap, the part has to be replaced.
