Thread: 300tdi doughy when cold

Originally Posted by jskerm

Re-check the timing. I had a defender that was gutless when cold and blew a lot of white smoke, mainly when first started and when engine was coming down from high idle, ie coasting. I did the timing belt and found the engine to be retarded quite a bit. White smoke is unburnt fuel, as long as it's not steam. I have since, whilst tinkering, advanced a 300 tdi too much and found it did the same, went like stink when it was warm but couldn't handle the advance when it was cold. I am not 100% but im pretty sure that these engines have an automatic advance on cold start up. Ie the engine advances itself slightly until warm. If your timing is set up to be advanced, the autoadvance can move it to far forward, making it smoke.
So anyway, that's where i'd start, check the timing.....

Timing is 100% spot on. I set it up as per the book, and rotated the engine several times and rechecked. Even used a phone camera to take a pic of the cam marks from the right spot - since you can't look straight at them with the AC rad and grille still in place.

Some more info. When you start it without glowing, it still starts quite well, and doesn't blow white smoke until about 10 seconds later. When you try and rev it while stationary it will rev till 1500 rpm, and then sit there for 3 seconds or so before reving higher. As I said it needs to be driven for at least 100m until it has warmed up enough. It then drives normally and doesn't blow any smoke at all under any conditions.

Haven't had a chance to sort it yet, however lots of good suggestions to try...