Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1987STEP VAN P20, 7.4 W, AUTOMATIC, 475/M40REPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCEADJUSTMENTTUNE-UP - DIESELTESTINGENGINE COMPRESSION
1987 Chevrolet Step Van P20, 7.4 W, Automatic, 475/M40
Engine Compression
1987 Chevrolet Step Van P20, 7.4 W, Automatic, 475/M40SECTION Engine Compression
NOTE:
Do not add oil to cylinders during compression check as extensive engine damage will result.
Remove air cleaner. Disconnect wire from fuel injection pump solenoid terminal. Disconnect glow plug wiring, and remove all glow plugs. Use Compression Gauge (J-26999-10) to test individual cylinders.
COMPRESSION SPECIFICATIONS
| Application | Specification |
|---|---|
| Compression Ratio | 21.3:1 |
| Compression Pressure | 300 psi (21 kg/cm2 ) |
| Max. Pressure Variation | 20% |
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.