More advice when buying a second hand turbo
https://youtu.be/NppUu3O7ND4
Exhaust Gas Recirculation valve – What’s inside?
https://youtu.be/VDuiCJBBgE4
Just a quick video explaining some important facts about the EGR valve and control solenoids and what to be aware of if buying a used turbo for the XUD turbo-diesel engine. (1.9 and 2.1 engines as fitted to Citroen Xantia, XM, Peugeot 206, 306, 405, 406 and 605). The tips and facts could also be applied to any make of diesel/turbo-diesel that uses conventional mechanical fuel injection. Exhaust gas recirculation is fitted to reduce oxides of nitrogen but more importantly to lower exhaust gas temperatures thus reducing thermal load on the turbo unit. Generally turbos on diesel engines are less heat tolerant than those fitted to petrol engines. One of the side effects of deliberately blanking off or a stuck (in closed position) EGR valve is overheating of the turbo shaft seals which eventually cook which over time allows engine oil to be drawn in and burned along with the fuel. Another symptom is intercoolers contaminated with oil. A light misting is ok but heavy contamination indicates either oil is being forced into the induction system via worn compressor seals or the crankcase is being pressurised due to blocked breathers, malfunctioning PCV unit, or worn bores or rings, worn valve seats – in short a well worn engine.
The XU diesel is generally long lived – IF regularly serviced – but it is NOT ‘bomb proof.’ It doesn’t tolerate lack of servicing or extended oil change intervals. These engines need 6,000 mile oil & filter changes using good quality oil.
Also carry out two basic checks which apply to any turbo whether petrol or diesel fitment;
1. Spin compressor and ensure turbine also spins smoothly. It’s not unknown for shafts to snap due to sudden oil starvation, thermal overload and seizure or foreign object ingestion. Take a torch (flashlight) with you so you can check it properly.
2. Compressor should turn smoothly with no roughness, binding, or tell-tale signs of blade contact with the housing. Also make sure the compressor blades are intact with no chunks missing.
Post time: Jun-21-2017