Tetsu0san Posted October 22, 2013 Share Posted October 22, 2013 Hi all I have been reading up on this quite a bit and I think I know the answer, but I thought I would ask on here anyway. And sorry for the long post... As a background, I replaced the timing belt on my 200Tdi about 6 months ago and ever since then I have a puff of black smoke when she starts and a little bit of white smoke on the over run, and she is a bit lumpy when cold. Once warm there is no white smoke and she runs fine. Before I got the engine I know the pump had been messed with but it never caused any problems in the Discovery the engine is out of... Anyway, I was away over the weekend, went to Center Parcs in Longleat (lovely place, loads to do and what a great swimming pool!!) and on the last day I had to go and get the car form the car park and drive to the villa (large shed) where I was staying. Now, to get to the villa you have to drive at 10mph max and the area is very hilly and this is where I noticed that I have a shed load of white smoke on the over run. When I was in 1st or 2nd gear, just coasting down the hills using the engine to brake there was quite an impressive white cloud of smoke out the back which disappeared when you hit the throttle or start to go up a hill. I never noticed it this bad at home as I live on a flat bit of road and I don't have to use any engine braking. The engine doesn't use any water or oil, there is no pressurising of the coolant system so I am certain this must be a timing issue. The problem is that I don't know why this would be, or even how to properly adjust it. When I did the timing belt I used a locking pin in the injector pump, a proper locking pin in the flywheel and everything lines up OK. I rotated the engine a few times before I put the timing case back on too. The only uncertainty that I have is the cam timing. I am as certain as I can be that this was OK too, but without taking the front off the engine I can't be 100% sure. If this was one tooth out either way, could this be the problem? Also, as a side note, when you are driving and you lift off to change gear there is a sort of burbling noise. Sounds a bit like a fart in a bath. From what I have read everything points towards the engine being a little retarded. Would you agree? I am going to check the valve clearances as this is an easy thing to do and I am going to try what I have read about undoing the 3 bolts on the injector pump and just try advancing it a little, but this brings me onto my main question. Surely, with the flywheel locked in place and the injector pump also locked in place, how much adjustment can you have on these 3 bolts? Would there be enough to actually make a difference? And has anyone had any experience of this on their engine? I have read that people use a drill bit for the pump locking pin and use a slightly smaller one when adjusting the timing. I used a genuine pump pin for the whole thing (something I picked up at Newbury a few fears ago) and so I thought I had it done right. Any help would be great Quote Link to comment Share on other sites More sharing options...
Puffernutter Posted October 22, 2013 Share Posted October 22, 2013 The injector pump can be moved about a 1/2 tooth each way. There are two other adjustments on the injector pump that can be changed as well. Try this link - see if it helps http://www.stonefisk.com/doc-arc/def_man/ThermoGuard_Tdi_Tuning_Rev.2.pdf Cheers Peter Quote Link to comment Share on other sites More sharing options...
Tetsu0san Posted October 22, 2013 Author Share Posted October 22, 2013 The injector pump can be moved about a 1/2 tooth each way. So it is possible that it could be as much as a whole tooth out. That might explain it! There are two other adjustments on the injector pump that can be changed as well. Try this link - see if it helps http://www.stonefisk.com/doc-arc/def_man/ThermoGuard_Tdi_Tuning_Rev.2.pdf Yeah, this could also be the problem I suppose as I have no idea what has been done to the pump. Might be good to get it back to some sort of normality. But if the cam is out, could this do the same? Quote Link to comment Share on other sites More sharing options...
steve b Posted October 22, 2013 Share Posted October 22, 2013 All tdi's give a puff of black smoke on start up , the VE pump opens the governor full on start up as fuel enrichment . a bit of steam when cold at low revs is also normal for a good diesel - my 2 1/4 diesel used to produce steam at tickover after a rebore and pistons. All sounds normal to me cheers Steveb edit incorrect info out Quote Link to comment Share on other sites More sharing options...
Tetsu0san Posted October 22, 2013 Author Share Posted October 22, 2013 Cheers to Puffernutter and steve b for the replies, any help is always welcomed. However, I have just had a look and it seems I found the issue. The injector pump pin In the timing pin kit that I got from Newbury is too slightly too small to be a snug fit in the pump. So when I timed it up after the belt change it all looked OK but in looking at it now and after undoing the 3 bolts that hold the pulley to the pump I found that I could move the pump quite a bit in the other direction. So basically the pump was retarded by quite a bit. So I have just advanced it to the opposite end of the play and it looks a shed load better. Fires up fine, revs straight away without being lumpy and it seems to pull really well. It's too dark to see the white smoke but I suspect that will be fine. However I think I may have gone a little too far with the advance but the heavens opened and I had to stop. I will look again when the rain stops. But a result either way! Quote Link to comment Share on other sites More sharing options...
vulcan bomber Posted October 22, 2013 Share Posted October 22, 2013 All tdi's give a puff of black smoke on start up , the VE pump opens the governor full on start up as fuel enrichment . a bit of steam when cold at low revs is also normal for a good diesel - my 2 1/4 diesel used to produce steam at tickover after a rebore and pistons. All sounds normal to me cheers Steveb edit incorrect info out Erm, no, the govenor doesnt open right up at all, if it did you'd fill the county with smoke not just a small puff of it. The pump has a spring in it that does lift the govenor off the stop, but not very much, its just enough to give the engine a helping hand to start. once the engine is running the spring is compressed by the govenor, the govenor then sits against the max fueling screw and the engine idles smoke free. The start spring comes into play again if the engine RPM drops so low it just runs, the spring will then expand, allowing more fuel, you will then get the same puff of smoke and the engine will (hopefully) settle into its idle again. Quote Link to comment Share on other sites More sharing options...
steve b Posted October 22, 2013 Share Posted October 22, 2013 Ah ok that's a more comprehensive reply than I had from the local IP specialist ..would you agree that it sounds pretty normal otherwise? cheers Steveb Quote Link to comment Share on other sites More sharing options...
smallfry Posted October 22, 2013 Share Posted October 22, 2013 The pin through the pulley does NOT actually give you correct pump timing, all it does is to put the pulley in the right place in relation to the crank and camshaft. It will give more or less the correct timing once it has actually been set, for the purpose of changing a belt, but if you suspect it has been "messed about with", I would be inclined to check it. Belts stretch slightly (or the teeth wear) over their lifetime, and this will retard the timing slightly, and this "softens" the engine a little, and sometimes when you change a belt, you notice that that the engine has a louder clack, as the new belt has advanced it again. To check the timing properly, you need to use all the pins in position , but screw a dial guage in the back of the pump to measuse the pump "lift". This is measuring the pump piston climbing a ramp, which is pressurising the injector pipes in turn. More lift is advancing timing, and less lift is retarding it, and you alter it by loosening of the three pulley bolts and the bolts holding the pump to the timing case. You will actually be turning the pump. The pulley in fact stays where it is. Its all hard to describe, but easy to see if I had a diagram. It is easy enough to do, and I have the stuff to do it i you wanted to smoke your way here, gassing flowers and wildlife in your wake.................. Quote Link to comment Share on other sites More sharing options...
simonb Posted October 23, 2013 Share Posted October 23, 2013 The pin through the pulley does NOT actually give you correct pump timing, all it does is to put the pulley in the right place in relation to the crank and camshaft. It will give more or less the correct timing once it has actually been set, for the purpose of changing a belt, but if you suspect it has been "messed about with", I would be inclined to check it. Belts stretch slightly (or the teeth wear) over their lifetime, and this will retard the timing slightly, and this "softens" the engine a little, and sometimes when you change a belt, you notice that that the engine has a louder clack, as the new belt has advanced it again. Just done my 300Tdi belt and yes can confirm it does sound a little more harsh. When fitting the new belt, the old one had stretched as the new one wouldn't fit between the cam and FIP sprocket without slackening the 3 small bolts on the FIP sprocket first. Also, I noticed this and the previous time I changed the belt, a new belt results in a far smaller puff on smoke on start up, than an old belt. Probably as a result of the timing being more "spot on" with a new belt and hence the engine firing quicker and better combustion. I've got the MOT next week, so I'll see if the emissions are improved/reduced. Quote Link to comment Share on other sites More sharing options...
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