T4 ACV 2.5 TDI injector pump errors

[fargo]

All that needed to happen for the belt to get in that condition is dodgy tension (which is spectacularly easy to do) and then it'd shred in a heartbeat. Replace the belt,tensioner, pulleys AND the bolts, get it timed up and it should run fine...fingers crossed. The belt itself only has a mechanical influence on the pump, not electrical so it won't affect any solenoids etc.

By the by, it's not really a DIY job unless you know what you are doing both physically and computationally...and have all the right gear.

Going to give it a crack myself. I have already sourced aftermarket(genuine) parts. $150 from Imparts. tensioner, idler & belt.
Read a bit about the procedure. I think I will try it without pulling off the rocker cover & jsut going off TDC1 on the flywheel.
I've ordered a USB-ODBCII & I have downloaded VCDS Lite ready to upgrade to use the timing plugin.
having trouble finding pictures on line of where the timing marks ae on the pump.
Could probably do with workshop manual on that section too if anybody knows of an online source for that.

[jets]

I think I will try it without pulling off the rocker cover & just going off TDC1 on the flywheel.

I agree, no need to remove the rocker cover. There should be a plug in the hole so that you can see the flywheel mark. This can sometimes be difficult. The pointer is cast into the gearbox housing & is hard to see looking from directly above. The timing mark is also hard to see & I worked on one where there was no mark at all. We had to make a mark by removing an injector & turning the crank until the no1 was at TDC & observing the movement of a screwdriver inserted in the hole.
I can't help with the timing mark on the inside of the pump pulley. I know there is one but I don't know what it is supposed to line up with.
When I remove that belt I lock the pump so that it can't move. You don't have that luxury but I will have a look & see if I can find any info on the T4 Forum.

[fargo]

Thankyou jets

[jets]

Go to post #3 on this link.

injection pump timing on 2.5tdi - VW T4 Forum - VW T5 Forum

Here's another link.

Pump timing advice please ? acv engine - VW T4 Forum - VW T5 Forum

And another.

T4 1999 2.5Tdi Error 17656 / Timing - VW T4 Forum - VW T5 Forum

[fargo]

Thanks Jets. I put the parts on over the weekend. Fired first kick & running fine now.
I read a few different articles & I have a few discrepancies. I found 2 articles that stated the fron tensioner bolt to be tensioned to 15nm & the rear to 20nm. Then I read another that suggests 70nm for both.
Also, not having done this before I was unsure as to how to fit the idler. I rotated the idler until the inside casting bracket pushed against he engine & could spin no further. The instructions for the front tensioner were straight forward in lining up the marks. However I am concerend that perhaps i have not nough tension on the tensioner bolt & idler nut & also if I have too much tension on the belt.

[Snail Style]

From memory the tensioner rotates until a marking lines up flush with the head. Not 100% on that, maybe one of the others can chime in.

Tensioners will be torqued to 20nM, the cam sprocket will be the 70nM one.

[fargo]

The front tensioner goes in with the hex key opening centre line of the 2 markers.Once finger tight you rotate the tensioner until the markers line up & tighten.
The rear idler doesnt appear to have any system other than when you roate it clockwise, it will butt up against the engine & will not rotate anymore.

[jets]

I found 2 articles that stated the front tensioner bolt to be tensioned to 15nm & the rear to 20nm. Then I read another that suggests 70nm for both.

According to Elsa Win "turn idler roller until the indicator aligns with the cylinder head flange contour. Tighten securing nut to 20Nm"
The tensioning roller securing bolt is tightened to 15Nm. I'm not sure on the pump belt tensioner but on the cambelt end, over tightening can crush the housing inside & wreck it. I would not be tightening to 70Nm.

The tension in the belt is determined by the position of the pointer on the tensioner.

[fargo]

Thanks Jets. That is what I did with the Idler. it didnt make sense to leave it "floating" & when it mated up to that contour, it just seemed "right".So you think the tension on the belt is correct if I algined those marks according to the instructions?
Im kind of surprised how easy the job was actually. All those articles you linked to were a great help.
Might even contemplated doing the timing belt after this experience.

[jets]

So you think the tension on the belt is correct if I algined those marks according to the instructions?

It should be fine. One other piece of advice, if you haven't read it already is if you tension too far & the pointer doesn't line up, you must not just turn it back. The clamping screw/nut[can't remember which it is] is undone & you start again. Not doing this can ruin the tensioner.
Replacing the cam belt is more time consuming & awkward because you are working in a confined area & from underneath.
The cam position is set after first removing the pulley on the end that you have just been working, undoing your previous work.
That is why that is recommended that both belts are replaced at the same time. But as Snail Style has said, some just replace the cam belt to save time & money. After all, if the pump belt fails it doesn't wreck your engine.