Help with hard starting after Timing Belt change

[alanmccormack]

I wonder if I can get some help/ advice from members that know a bit more about these engines than I do?

I have a 2004 Mk4 Golf 1.9 TDi PD (with ATD engine) on 193,000 miles and I've just changed the timing belt (and water pump) with a Contitech kit, I used the Sealey Timing tools to lock both the crankshaft and camshaft, I followed a very good online guide and was extremely slow and careful.

The change went very well and the car seemed perfect last night after I finished. I took it for a drive and it all felt very good, it pulled and drove well - as it always did. I was quite pleased with myself as it's a big job.

However this morning I've been having problems starting it and that's never happened before. It’s always been a very good starter, always starting on the first turn of the key, but now if I turn it off for more than 5 minutes then it takes a good few seconds to start (5 – 10). It always starts (so far anyway) and once it does it is absolutely perfect, it just concerns me because this has only happened after the belt change.

I wonder if I’ve inadvertently buggered up something g else? It feels like the fuel is taking longer than it should to reach the engine. Is there something that needs to be done with the injection pump? Can this pump be adjusted?

Or could I just have a bad case of air in the fuel lines with all the disturbing and dismantling I did? But it doesn’t seem to be settling down, it takes a long time to start every time.

I don’t have VAG-COM or VCDS, is it a necessity to get this? Or is there any checking/ adjustments that I can make without this? Any ideas much appreciated.

TIA

[Rob69]

You wouldn't normally disturb any of the fuel system when doing the belt. You might want to confirm the glow plugs are coming on and you haven't knocked anything off. It would have been good if you'd been able to check the camshaft setting or 'torsion values' before the belt change then check them after to see if you had set the camshaft back to the previous position but you need vcds for this. The locking pin used in the camshaft sprocket seem to allow a slight variation and you possibly have the camshaft a fraction out from its previous setting. any adjustment of the camshaft + or - without vcds would just be trial and error. The injectors are also the the pumps on these engines, the tandem pump at the end of the cylinder head is not timed to the engine in the old fashioned sense.
I did do a belt on my old touran 1.9pd and swung the fuel filter out of the way without disconnecting it, when I restarted the engine it coughed a bit as I think I'd drawn some air in from the top of the filter but this cleared within seconds.

[micheal balbrig]

probably only minor adjustment required,but more important is the tensioner bolt issues which you may have read about.

[alanmccormack]

It would have been good if you'd been able to check the camshaft setting or 'torsion values' before the belt change then check them after to see if you had set the camshaft back to the previous position but you need vcds for this. The locking pin used in the camshaft sprocket seem to allow a slight variation and you possibly have the camshaft a fraction out from its previous setting. any adjustment of the camshaft + or - without vcds would just be trial and error. The injectors are also the the pumps on these engines, the tandem pump at the end of the cylinder head is not timed to the engine in the old fashioned sense.

Thanks Rob, you were on the right track and I found that helpful. It shows that really I should've got my hands on VCDS before attempting this job, but I didn't know that at the time, I just blundered into it being the hapless macho man thinking I can fix anything!


OK, a bit of an update, a uk-mkivs.net user called GerryWac, thought similar to you Rob and he pointed me in the direction of this article:


Camshaft timing (torsion value) adjustment on VW and Audi PD TDI engines | VW TDI forum, Audi, Porsche, and Chevy Cruze diesel forum


I don’t have VCDS, so I couldn’t check anything electronically, but I understood that the gist of the article was that you could ‘fine tune’ the timing by adjusting the camshaft sprocket.


I’ll explain what I did just in case somebody else finds this helpful in the future. It’s not a big job.


I knew that the only thing I had ‘changed’ was the timing by replacing the timing belt, so I was happy that my hard starting issue was a timing issue caused by me. I had also read that if your timing is too far advanced then it can be hard to start the car and sure enough when I looked at the position of the sprocket it was as far advanced as it could go, as the 3x 13mm bolts were jammed up against the far right of their elongated slots (or as far clockwise as they could go). This hadn’t been a conscious thing; it was just where they ended up after using the timing tools when changing the belt. So I could see that there was plenty of scope to retard the timing.
DSC00217-3600.jpg

I loosened the 3x 13mm bolts and turned the big 18mm bolt anti-clockwise, this had the effect of moving the camshaft back, retarding the timing slightly. You can see in the photo that the bolts are still pretty ‘clockwise’ in their slots. I hardly moved the sprocket at all but it had the desired effect and now the car starts on the first turn of the key -- Yay!

[Rob69]

OK nice one - looks like your trial and error paid off !!!