Service Manual

Crankcase Blowby, Measure ISB, ISBe and QSB (Common Rail [...]
Page 14-30 Section 14 - Engine Testing - Group 14
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The following charts show the relationship of measured pressure to flow rate, depending on the blowby tool used.
Blowby Conversion Table (5.61-mm [0.221-in] orifice, Blowby Tool, Part Number 3822476)
mm [in] of H
2
O Liter [cfm] per Minute
25.4 [1] 27 [0.953]
50.8 [2] 40 [1.413]
76.2 [3] 48 [1.695]
101.6 [4] 58 [2.048]
127 [5] 64 [2.260]
152.4 [6] 71 [2.507]
177.8 [7] 76 [2.684]
203.2 [8] 81 [2.860]
228.6 [9] 86 [3.037]
254 [10] 90 [3.178]
279.4 [11] 94 [3.320]
304.8 [12] 98 [3.461]
330.2 [13] 102 [3.602]
355.6 [14] 105 [3.708]
381 [15] 109 [3.849]
406.4 [16] 112 [3.955]
431.8 [17] 115 [4.061]
457.2 [18] 118 [4.167]
482.6 [19] 121 [4.723]
508 [20] 124 [4.379]
533.4 [21] 128 [4.520]
558.2 [22] 131 [4.626]
584.2 [23] 135 [4.767]
609.6 [24] 137 [4.838]
635 [25] 140 [4.944]
660.4 [26] 144 [5.085]
685.8 [27] 147 [5.191]
711.2 [28] 150 [5.297]
736.6 [29] 154 [5.438]
762 [30] 157 [5.544]
787.4 [31] 160 [5.650]
812.8 [32] 163 [5.756]
838.2 [33] 166 [5.862]
863.6 [34] 169 [5.968]
889 [35] 172 [6.074]
Blowby Conversion Table (7.67-mm [0.302-in] orifice, Blowby Tool, Part Number 3822566)
mm [in] of H
2
O Liter [cfm] per Minute
25.4 [1] 50 [1.766]
50.8 [2] 84 [2.966]
76.2 [3] 103 [3.637]
101.6 [4] 119 [4.202]
127 [5] 133 [4.697]
152.4 [6] 145 [5.121]
177.8 [7] 155 [5.474]
203.2 [8] 164 [5.792]