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Needing to convert degrees to
Torque Angle is supposed to be a "more scientific and precise way to gauge the "clamping force" applied to a bolt. This idea appeared about 20 years ago and is now, sadly, becoming universal on newer vehicles. The idea behind Torque Angle is that using the old foot-pounds torque wrench would not give you the kind of *exact* repeatable torque that you get using a breaker bar with a Torque Angle meter attached.
Unfortunately, there is no precise way of converting between Torque Angle and Foot Pounds. The best you can do -- and it will work -- is figure each "point" on the head of a 6-point bolt is equal to 60 degrees of Toque Angle (360 degree circle of the bolt head divided by the 6 points) and do the following:
Do NOT use a torque wrench with this technique -- instead you must use a long breaker bar with the correct size socket attached (for this kind of heavy duty torquing a 1/2 breaker bar and socket would really be best):
Per the instructions you gave in your question, you would mark one of the six points on the bolt head and make a corresponding mark on the surface of what you're working on. Then turn the bolt so that the marked point turns away from the surface mark until the next point on the bolt reaches the surface mark.
You've just turned the bolt as close to 60 degrees as you're going to get without a Torque Angle meter (which I have found be very difficult if not impossible to use correctly in most real world cases anyway). This approximate 60 degree turn you just made is close enough to the first 55 degrees stated in the instructions. Same would be true for the next two measurements. Move the next point on the bolt to line up with the surface mark and finally turn the next point after that to the surface mark. As an engine mechanic of 40 years experience, I feel this end result is close enough because with that kind of a torque requirement you are really going to be cranking that bolt down and a few degrees of angle isn't going to matter by the time you do the last torque.
Using a Torque Angle meter may be just fine if you're working on the factory floor, but for everyone else I personally think Torque Angle is another case of "newer ain't necessarily better".
on May 21, 2019
I have a 1999 Chevrolet Suburban 1500, 350 V8,
check the fuel system
pump, regulator, fuel pressure damper , return valve
when the key is on the system needs to be pressurized and maintain pressure, if you dont have this , recheck your fuel system
if everything is ok, than cranck the engine and look for injector fault
on Nov 07, 2017
2000 5.3ltr silverado will not start
Which ECM / PCM fuse was burnt ? How did you check fuel pressure ? With a pressure gauge or just pushing the scrader valve an seeing fuel dribble out ? Pull a plug wire an see if there is spark .
Engine Cranks But Does Not Run
The Engine Cranks but Does Not Run diagnostic table assumes that the battery condition and the engine cranking speed are OK. If the battery condition and the cranking speed are not OK, refer to Diagnostic System Check - Engine Electrical in Engine Electrical for diagnosis. Make sure that there is adequate fuel in the fuel tanks.
• Check the duct work between the mass air flow (MAF) sensor and the throttle body for air leaks.
• A malfunctioning MAF sensor may cause a no start or a stall after start. If you suspect this, disconnect the MAF sensor. The powertrain control module (PCM) will default to the speed density in order to calculate the load and the air flow. If this corrects the condition and the connections are OK, replace the MAF sensor.
If the steps above check OK, refer to Symptoms .
The numbers below refer to the step numbers on the diagnostic table.
It may be necessary to connect a battery charger to the battery for this step. If the battery state of charge is low, the scan tool may reset during the cranking test.
This step tests the ignition relay for proper operation. The ignition relay supplies voltage to the injectors and the ignition coils. When the ignition relay is not operating properly, a no start condition occurs. If the test lamp does not illuminate, this indicates the ignition relay is not suppling a voltage to the fuses.
The crankshaft position (CKP) sensor is located above the starter.
The camshaft position (CMP) sensor is located at the rear of the engine behind the intake manifold.
The ignition feed circuit for the CMP and CKP sensors is internally connected within the PCM. A short to ground on either circuit will cause a no start condition.
The fuel cap may need to be removed in order to hear if the fuel pump is operating.
At this point the engine should start. Refer to Hard Start for further diagnosis.
on Mar 23, 2017
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