1.9tdi cold start update

[johnnyroper]

Despite me thinking it was torsion value causing difficult starting after being stood for a while the problem was still there occasionally.

After doing lots of research on the net I decided to look at the tandem pump as some of the people on the golf board seem to have had similar problems. Some changed pumps whilst others nipped the bolts up or resealed.
Turns out the LUK made tandems can have a very slight leak when cold from the end plate causing chamber to drain enough fuel/allow air in. Unlike the Bosch sourced tandems there is not a seal kit available unless you are an authorised repairer.
I decided rather than buy a new tandem I would pop the cover off and see about resealing it. Most sealants are not suitable for constant fuel contamination so I used some hylomar blue on it after a good clean up.
Bit of a pig to restart but since then cold starts have been pretty much instant.
Just thought I would update in case anyone else is having similar issues with up to 15 seconds cranking then spluttering in to life with a cloud of smoke.
Nice cheap fix especially as I was having tandem off to change pump to head seals anyway.

[insanitybeard]

Interesting info, are the seals you mention internal to the tandem pump and not the ones shown on the parts diagram?

Mine has had an occasional issue where it starts fine from cold but if I drive a short distance and stop the engine before it's properly warmed up it can be a total pig to restart. I wonder if this may be anything to do with what you mention here. It doesn't happen frequently though, and hasn't done it for some time now.... must be due! 

[johnnyroper]

The ones shown are between pump and head old luks have 2 rubber the newer design has the metal plate type.
The one on mine was internal sealing main case and the end plate with the 4 or 5 torx bolts on.
After reading more it seems to be very common with these pumps and there have been numerous reports of the hose on water housing underneath failing due to fuel contamination over time.

[insanitybeard]

Was your pump leaking enough fuel to make the top of the gearbox wet then?

[johnnyroper]

Over a period of time it was but mainly it was letting air in to the pump. The trace of fuel I thought was staining from when I had head off,changed filter etc..