IE B056ACT AND MEMO OF THE DIAGNOSTIC STATION
SISU bus: fuel pump treatment raised power without teardown
Power under load rose, heavy black smoke gave way to medium smoke, signs of plunger pair wear disappeared. 18.2 % — power under load in 4th gear, 110 → 130 kW; 10 % — power under load in 5th gear, 100 → 110 kW (Russia · 2001).
and memo of the diagnostic station“Approved” endorsement by the technical director of the enterprise
Key results
| EQUIPMENT | CONDITION BEFORE TREATMENT | WHAT WAS MEASURED |
|---|---|---|
| SISU bus, reg. No. 216<br/>diesel, 6 cylinders | Heavy black smoke, signs of wear of the injection pump plunger pairs, the vehicle does not hold load at 50 km/h | Power under load in 4th and 5th gear, injection pressure and duration, idle speed |
Power under load
| PARAMETER | BEFORE TREATMENT | AFTER TREATMENT | CHANGE |
|---|---|---|---|
| Power in 4th gear, N₄ | 110 kW | 130 kW | +20 kW |
| Power in 5th gear, N₅ | 100 kW | 110 kW | +10 kW |
| Minimum idle speed | 610 rpm | 660 rpm | +50 rpm |
The same power values are independently stated both in the act and in the memo of the diagnostic station.
Fuel injection parameters
| IDLE MODE | PARAMETER | BEFORE | AFTER |
|---|---|---|---|
| 577 → 600 rpm | Maximum injection pressure, Pmax | 14.6 MPa | 15.1 MPa |
| 1100 → 1110 rpm | Maximum injection pressure, Pmax | 15.7 MPa | 15.8 MPa |
| 1100 → 1110 rpm | Injection duration, T | 1.5 ms | 1.0 ms |
Injection pressure is held by the worn plunger pair — the rise in Pmax is itself the sign of restored pair geometry, and it is what delivers the power gain.
Engine condition before and after treatment
| INDICATION | BEFORE TREATMENT | AFTER TREATMENT |
|---|---|---|
| Smoke during power measurement | Heavy, black in colour | Moderate, grey-blue in colour |
| Behaviour under load | “Absolutely does not hold load at 50 km/h” | Power gain in both measured gears |
| Injection oscillogram | Significant wear of the injection pump plunger pairs | “Signs of plunger pair wear have disappeared” |
Smoke was assessed visually by colour and intensity of the exhaust during the power measurement.
Conclusion of the enterprise diagnostic station
Current equivalent
- Revitalizant gel for diesel enginesDiesel engines
- XADO “Restorative” greaseFriction pairs · joints
How such units are treated:
Limits of this report: The results refer to the diesel engine of a SISU bus after a single treatment of the fuel injection equipment; on other equipment and with a different condition of the units the figures may differ. In the 2001 document the compound is called a repair-and-restoration compound (XADO RVS): RVS is an outdated XADO designation, zero-generation compounds; the current product generation is revitalizants.