Flexigauge is precision manufactured plastic strip.
It is available in four sizes and is used to check clearance of main and connecting rod bearings, and is suitable for Automotive, Marine and Industrial applications.
The four sizes available together cover clearances from .001 in to .016 in, or .025mm to .406mm and as
Reference: Covers Clearance Between:
AG-1 - (RG-1) (Green Pack) .001 - .003in or .025 - .076mm
AR-1 - (RR-1) (Red Pack) .002 - .006in or .051 - .152mm
AB-1 - (RB-1) (Blue Pack) .004 - .009in or .012 - .229mm
AY-1 - (RY-1) (Yellow Pack) .008 - .016in or .203 - .406mm
Flexigauge strips - 12 in long - are packed in individual envelopes, which are marked in appropriate graduation - one side in thousandths of an inch and the other side in millimetres. Ten strips in their envelopes are packed in their appropriate coloured carton.
Directions for use, which are printed on the outside of each carton for easy reference, are as follows:
1.Remove the bearing cap, wipe the journal and bearing shell clear of oil.
2.Place a piece of Flexi gauge across the bearing at the crown (see Figure 1).
3.Install the bearing cap and using a Torque Wrench tighten the bolts to the correct tension.
DO NOT REVOLVE THE SHAFT OR BEARINGS.
4.Remove bearing cap. The Flexigauge will be adhering either to the bearing or shaft.
5.Compare the width of the flattened Flexigauge with the graduation of the envelope. The figure within the graduations indicates the clearance in thousandths of an inch of millimetres, depending on which side of the envelope is used. (See Figure 2)
6.Taper is indicated when Flexigauge is wider at one end than the other, the amount of taper being the difference between the readings. The widest part of the Flexigauge represents the area of least clearance. “Barrelling” of the shaft when the Flexigauge is wider in the centre of the bearing.
P R E C A U T I O N
When checking main bearings, with the CAP supporting the crankshaft, the weight of the crankshaft and flywheel must be taken off the bearing caps to avoid inaccurate results. This can be done, for example, by ‘ jacking’ on the crankshaft balance weight. Main and connecting rod bearing clearances should be checked on the area of least journal wear. Main bearing checks should be made with the adjacent crank pin situated about 30 degrees after bottom dead centre.
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