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Mounting with correct assignment | Pierburg | Motorservice

Vacuum pump damage due to incorrect assignment

Pierburg | Motorservice
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Information on diagnostics

Mounting an incorrect vacuum pump can cause severe and expensive engine damage. Which vacuum pump fits which engine? What is the correct way to install the vacuum pump? Find out why it is important to check the chassis number, registration date and part number before mounting a vacuum pump here.

Incorrect vacuum pump assignment often occurs due to a change of cylinder heads in the VW T4 engine with the code letter AAB. If an incorrect pump is installed, claims cases will not be recognised.

In order to prevent damage, it is essential to check the chassis number, registration date and/or the part number of the old pump!

ATTENTION


 
If an incorrect pump has been mounted, this will lead to breakage of the pump housing (see Fig. 1) during the initial engine start following installation, or even to breakage of the camshaft – and therefore to severe and expensive engine damage.                                                     
Breakage in the pump housing | Motorservice
Fig. 1: Breakage in the pump housing
 Comparison of vacuum pumps | Pierburg | Motorservice
Fig. 2: Comparison of vacuum pumps

Vehicle: VW Transporter LT, T4 (platform, bus, truck, California), engine classification code: AAB

Pierburg no. 7.22300.62.0 7.22300.69.0
Replacement for 7.22300.12.0 7.22300.19.0
Model year up to 5/1994 from 5/1994
Chassis number up to 70-R-180 000 from 70-R-180 001
VW part number 075 145 100; 075 145 101; 075 145 101 A 074 145 100 A
VW cylinder head no. 074 103 351 A 074 103 351 D
Motorservice cylinder head no. 50 003 101 50 003 113
Cylinder head cover surface 11 holes; Ø 5 mm without holes
Pierburg tappet number 3.52124.06.0 3.52124.05.0
VW tappet number 075 145 307 074 145 307 B
Tappet length 71.0 mm 67.5 mm

CORRECT MOUNTING

In order to mount the pump with only a minimal amount of preload (max. 2 mm gap), the cam on the camshaft for driving the vacuum pump must be positioned on the opposite side of the connecting tappet (see Fig. 3) during mounting:

Position of the camshaft for installation | Pierburg | Motorservice
Fig. 3: Position of the camshaft for installation
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INCORRECT ASSIGNMENT – MOUNTING NOT POSSIBLE

If it is not possible to press the vacuum pump to the flange (approx. 5 mm gap) without great effort, even with the cam on the opposite side of the connecting tappet, an incorrect assignment has very likely taken place.

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It is essential to check the chassis number, registration date and/or the part number of the old pump! Never attempt to solve this problem by modifying the connecting tappet (e.g. regrinding)!

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