Compression Testing JASPER’s Complete Diesel Engine – UnderhoodService

Compression Testing JASPER’s Complete Diesel Engine

In its continuing effort to provide customers with the perfect product, Jasper Engines & Transmissions has improved the testing process on all of its Complete diesel format engines.

In its continuing effort to provide customers with the perfect product, Jasper Engines & Transmissions has improved the testing process on all of its Complete diesel format engines.

Depending on the application, a JASPER Complete diesel engine includes all major castings, valve train, oil pump, oil pan and pickup tube. “Each Complete engine is spin tested to verify oil pressure and water is run through the unit to check for fluid leaks,” says Eric Brittain, JASPER Diesel Division Group Leader.

As the Complete engine is spin tested, a compression probe is inserted into the glow plug hole of each individual cylinder (Figure 1). “The compression reading of that cylinder is recorded through computerized data acquisition,” said Brittain. “The program will alert the operator of any potential issues with low compression, or too great of a variation between cylinders.”

“On a diesel engine, the biggest issues are immediate start-up failures such as an oil leak, a misfire or a rough-running condition,” added Brittain. “By performing this test JASPER can pinpoint, and correct, potential issues.  When this process is finished, we know JASPER has provided the best product for the customer at the best price.” 

For more information on the remanufactured diesel engines of Jasper Engines & Transmissions, call 800-827-7455, or log onto

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