FIELD CASE|PASSENGER ROAD TRANSPORT|DIESEL · CYLINDER-PISTON GROUP
TREATMENT REPORT ON A MUNICIPAL FLEET BUS · ISRAEL, 2005
MAN city bus: worn diesel regained compression, no teardown
PRODUCTXADO compoundthree-stage treatment over ten days, without taking the vehicle out of service
TEST OBJECTMAN - 202 busdiesel engine, 6 cylinders, 141 hp · mileage 412 213 km
DOCUMENT TYPEReport by the XADO
representative in IsraelO.D.A.X LTD · company seal impression
representative in IsraelO.D.A.X LTD · company seal impression
Key results
compression evened out across the cylinders
↑7.7-25%
compression by cylinder, 22-26 → 27.5-28 bar
| VEHICLE | MILEAGE AT START OF TRIAL | WHAT WAS MEASURED |
|---|---|---|
| MAN - 202 bus, 6-cylinder diesel, 141 hp | 412 213 km | Compression in each of the six cylinders, bar |
Compression by cylinder — before and after treatment
| CYLINDER | BEFORE, BAR | AFTER, BAR | CHANGE |
|---|---|---|---|
| 1 | 25 | 28 | +3 bar |
| 2 | 25 | 28 | +3 bar |
| 3 | 25 | 28 | +3 bar |
| 4 — weakest | 22 | 27.5 | +5.5 bar |
| 5 | 25 | 28 | +3 bar |
| 6 | 26 | 28 | +2 bar |
| Spread across cylinders | 4 | 0.5 | −3.5 bar |
Baseline measurement taken 09.01.2005, control measurement 01.03.2005, 13 days after the third stage. All six cylinders reached 27.5-28 bar.
What this means
The engine came to treatment with 412 213 km on the clock and sagging compression: the weakest, fourth cylinder held 22 bar against 26 bar in the strongest. A spread of 4 bar is a sign of a worn cylinder-piston group: the engine runs unevenly and loses power. The three treatment stages took ten days, and the bus stayed on its route throughout — between the first and the last stage it covered 810 km. The control measurement gave 27.5-28 bar across all six cylinders: the weakest gained 5.5 bar, and the spread narrowed to 0.5 bar. Even compression means the sealing of the cylinder-piston group has been restored, and it cannot rise above the factory nominal: bringing every cylinder to one level is the maximum achievable. Obtained without dismantling the engine, on a vehicle in normal service.
The results apply to the diesel engine of a MAN - 202 bus with over 412 000 km of mileage; on other equipment and with a different condition of the components the figures may differ. The treatment was carried out and the result reported by the XADO representative in Israel — O.D.A.X LTD. The original document is published in full and available for download.
Current equivalent
- Revitalizant gel for diesel enginesDiesel engines
- Revitalizant gel for cylinder restorationEngine cylinders, deep wear
How such units are treated: