Product description

With every engine overhaul you have to replace all bearings, if the crankcase is drilled in line, or the crankshaft is ground, you need so-called under- or oversized bearings.

The crankcase must be line bored if the bearing bed is uneven and/or no longer of the correct size. The crankshaft can best be checked by sliding your nail over the bearing bed, if you notice unevenness, the crankshaft must be machined. Also when the size is different or when tit is disformed, grinding is necessary.

For most combinations under- or oversize is a suitable bearing to get. If there is too much play on the first main bearing (axial bearing), it is necessary to machine the seat of the bearing bed, also for this purpose bearings are available where the axial bearing is wider than standard. The term 'standard' means that nothing has been drilled out or polished off. To be on the safe side, measure this with a micrometer or purchase a bearing measuring device that allows you to determine exactly what the current dimensions are (see the related section).

Attention! If you need to machine the crankcase, first buy the bearings to make sure you use the exact measurements, this is a very accurate operation.
On the page where the selection takes place, under "specifications", the dimensions of the original crankcase, crankshaft and axial bearings are listed.
In the selection, the difference in lower or upper dimensions is mentioned, with the exception of the axial bearing, where the total dimension is mentioned.
Please note that bearings in open packaging cannot be returned.

Steel-backed bearings

Volkswagen produced bearings until the mid 60's where aluminium was the main component, later this was changed to so-called "steel-backed" bearings. A steel reinforcement has been applied to the bearing, making it less susceptible to wear and resulting in a longer service life. The suppliers of Volkswagen (Mahle and Kolbenschmidt) but also the after-market producers like Sintermetal have unfortunately stopped this, they only produce bearings from aluminium so without steel reinforcement. Silverline is currently the only brand in the world that still produces these type of bearings, in steel-backed version. For a standard motor this is not a problem but for a tuned motor where the bearings have to endure much more, only "steel-backed" bearings are recommended. The professional engine builder will not settle for bearings made of aluminium or there should be nothing else available.

Selecting the right bearing is done in a number of steps:

- select the width of the axial bearing
- select the undersize of the crankshaft
- select the oversize of the crankcase
- if available select the quality

All bearings are supplied in a set.