ELEC T RONIC PRE S S URE T R A NSDUCERS
The Power of Electronic Pressure Transducers Avoid an engine tear down with this tool B Y B I L L F U LT O N
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HE CONVENTIONAL COMPRESSION
gauge was only designed to conduct a WOT cranking compression test. When using this gauge, I have always taught that the second compression stroke is the one that should be monitored. The reason being is that by the second compression stroke we can be assured that a full intake stroke would have occurred. There are cases whereas we could have good WOT cranking compression values and yet the engine may be suffering from a retarded valve timing issue or a wiped exhaust cam lobe. When using the electronic pressure transducer coupled to your original compression gauge hose and interfaced with a DSO, we can conduct four separate compression tests. It is critical to keep the compression hose as short as possible. I believe that the maximum length should not
Fig. 1 Compression versus RPM chart. (all images courtesy the author)
exceed eight inches. This increases the accuracy of these four tests: WOT cranking, idle, cruise and WOT snap. Notice the compression versus RPM chart in Fig. 1. The idle, FEBRUARY 2023 | ASP
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