Econoline E350 1 Ton V8-7.3L DSL Turbo VIN F (1998)
Compression Check: Specifications
TEST RESULTS
The indicated compression pressures are considered within specification if the lowest reading cylinder is within 75 percent of the highest reading.
Refer to the Compression Pressure Limit Chart.
If one or more cylinders reads low, squirt approximately one tablespoon of clean engine oil meeting Ford specification ESE-M2C153-E on top of the
pistons in the low-reading cylinders. Repeat the compression pressure check on these cylinders.
INTERPRETING COMPRESSION READINGS
1. If compression improves considerably, piston rings are faulty.
2. If compression does not improve, valves are sticking or seating improperly.
3. If two adjacent cylinders indicate low compression pressures and squirting oil on each piston does not increase compression, the head gasket may
be leaking between cylinders. Engine oil or coolant in cylinders could result from this condition.
Use the Compression Pressure Limit Chart when checking cylinder compression so that the lowest reading is within 75 percent of the highest
reading.
