Pump timing (checked via vag-com) and leaking

Needs to get out more Joined: May 03, 2011 Posts: 119

Hi Guys,
I´ve purchased a few days ago an A6 2.5 TDI AAT engine and driving is is being a very good experience. I come from an A4 1.9 TDi AFN engine, which is also very good to drive, but the A6 has better sound proof and 6 speed is amazing !

But... it starts first time or maybe second in the morning and when hot it´s a pain to start. When it goes (let´s say about 4th time), there´s a big cloud of smoke which is kind of embarassing.
I´ve tried to see via vag-com where the timing was, but the engine starts to shake and to produce an enourmous cloud of white smoke which goes on and on. Is this normal when testing?

At the same time I found my pump is leaking from under or maybe from the side that is closer to the engine. Is this something that needs to remove the pump out to be fixed? Should I get prepared for a big bill? The car runs very fine and the idle is stable. No oscillations.
Nothing else is leaking, really... Confused

Apart from this, all else appears to be OK.

Thanks!
Regards from Portugal

Posted: Tue May 03, 2011 10:22 pm

Pump timing being too retarded will cause the smoking when going into basic settings for vag com timing graph..

you could try advancing the pump a little then retry, they start better advanced and still run way over advanced, to retarded and they smoke, wont run, and don't start easily.. to advance you want to turn the pump towards the cylinder head more.

you need to use the AAT / AEL 1200 rpm option in tdi timing graph..

see this topic for more details and my reasons.

http://www.audifans.net/ftopict-30042-.html

leaking from the secondary pump top seal is fairly common at this age.. make sure you mark the exact position of the top chamber part (not the lid) in relation to the pump body because it is adjusted to get the IQ (injection quantity)

think the seal is still available from audi

Needs to get out more Joined: May 03, 2011 Posts: 119

Hi Jon,
Been reading a lot of information from you and other members in this forum for quite a while, but only now I have purchased my C4 and there are these few things happening. Otherwise, I am very surprised with the building quality and riding confort.

When you mention "top chamber", you mean that part that is messed when people to the "hammer mod" ? So the leak proably comes from there? I can´t see any leak in the front area of the pump, it appears to be from the side of the pump that is closer to the engine or even under the pump, because the fuel is dropped into the engine block area.
I can buy a repair IT. Is this a VP37 or VP44 ?
OK, I mark the position so the IQ won´t be messed. Even if it´s not perfect...there´s still vag-com. My IQ is now 4,5.
The engine pulls very well and the idle is good.

I could actually try to advance the pump timing. Is this a difficult procedure? I have tried to search for the 4 bolts that hold the pump, but didn´t find them. Does the belt have to come off? The belt looks over tensioned, btw...

The Timing test was really embarassing. The engine was choking and smoking like hell !!

Posted: Wed May 04, 2011 7:56 am

It can also be the throttle control part on the side of the pump, but that doesn't usually leak unless someone has messed with it at some point..

The IQ will still need to be fine tuned if you take the top chamber off but you need to get it back as close as possible to where it was then any fine adjustments can be done in vag com using the login for your car 12233 from memory but I maybe wrong, search for the AEL login topic as I mention the AAT login in that tread.

The symptoms you are giving smoking and chugging when going into basic settings for timing adjust are that it is too retarded, possibly to retarded to plot, but it's hard to be sure because there are lots of hills and puddles blocking my view of your car Laughing

If it's still runs you should be able to see the timing graph, think you need genuine vag com for TDI timing check? I've only ever used a genuine one so not sure..

The pump has four bolts holding it. one under the injection pipes, one Allen bolt behind the pump near the sprocket the other two by the sprocket on the other side slacken off so pump will just move if tapped gently and you should be able to move it a bit. injection pipes will stop it from moving very much so it wont go miles out, but mark your current position so you have a datum to return to..

Needs to get out more Joined: May 03, 2011 Posts: 119

So, to set timing I don´t have to take the belt out.

OK, I´ll try doing it. Is there any "scale" that marks where the time is, or i´ll have to do an "own mark" myself somwhere?

My Vag-com doesn´t allow me to fine tune the advance (on my 98 Ibiza TDi it did). It´s not genuine but, let´s say... I can make it work.
I have checked the timing before in an Audi 80 and Ibiza and it worked. That´s why I got scared this time. Rolling Eyes

I´m worried about the diesel leakage. I am not sure where it comes from. I hope it´s a seal somwhere I can reach on my own without taking everything apart and spend a lot of cash. It sure comes either from the back or under the pump.

Needs to get out more Joined: May 03, 2011 Posts: 119

Hi,
I saw the IQ marks already and timing marks too. Got it.

I found the 2 bolts holding the pump near the sprocket and also the one near the metallic fuel lines. I´m just missing the one withthe Allen bolt in the back of the pump !

I think I will have to buy the seal kit for VP37, as all 3 main seals seem to be leaking. The upper and lower one in the head, and o-ring in the side, near the metallic fuel lines.
I´ve seen the procedure in youtube (3 or 4 sequence videos) and looks easy with the proper attention. Just tell me... can I rotate the engine by turning it from the Injection pump sprocket, or i´ll have to do it by reaching the other side of the engine (front of the car) ? This procedure is to place the internal spring of the pump holding all the bits against each other internally and nothing gets loose, so I can replace the O-ring safely.
Regards

Posted: Thu May 05, 2011 12:43 pm

never turn engine over via camshaft, either turn crankshaft using pulley bolt or for small amounts turn via starter ring gear teeth through the timing hole in the belhousing under the injection pump.. removing the glow plus makes this much easier..

Needs to get out more Joined: May 03, 2011 Posts: 119

I just pretend to turn it slightly so the pump spring is on full compression. So, I think i´ll try to do it via the starter ring teeth ( i dont know what it is in Portuguese ).

The rest of the process looks fairly easy. Just have to be carefull and patient. (I have swapped injectors sucessfully a few times already)

I´ll have a look under the injection pump and try to find out what you mean.

Have you ever swapped seals in this pump? I´ve just ordered the VP37 seal kit + special tool for the triangular bolt.

Needs to get out more Joined: May 03, 2011 Posts: 119

Ok, it´s leaking specially from the IQ part of the pump seal (lower joint). The Top seal appears to be OK.
Also the side O-ring (shaft O-ring?) appears to be sweating slightly, so i´ll have to change that one too.

Blade, How can I take the belt cover out? It looks like I have to remove the sock vibration absorber. And also... to buy a tool to rotate to engine, so the internals of the pump, actually the spring can compress. They actually say "rotate untill the pump is on Cam". This is in Video 2.

http://www.youtube.com/watch?v=VR44StvcXms&feature=related

This is the 1st of 7 videos. Looks like something I can do. Rolling Eyes

Just have to be carefull with the O-ring of the shaft.

Posted: Fri May 06, 2011 8:26 am

Not much time today due to work.. that video guide is good but I cannot belive they are turning engine over against cylinder compresion using the camshaft pulley.. that will be loading the cambelt in the wrong way and could potentially jump the belt or rip teeth / weaken the timing belt.. very very bad idea imo Rolling Eyes

If you must do it this way at least remove all the glow plugs so there is no compresion.. still not recomemnded.

I've not replaced the seals yet although I do have a pump with quantity adjuster seal leak

see this topic for images of the timing marks, (if it's an automatic it will be different these are from 6 speed manual)

http://www.audifans.net/ftopict-29112-timing.html

look for my reply that starts "Just found some installed images" to show where you can use flywheel ring gear to turn engine over.

*Edited* wrong link before

Needs to get out more Joined: May 03, 2011 Posts: 119

Hi,
By the second time I watched the video, I actually realized they did it on the camshaft Smile

Nothing broke actually , but If you tell me it´s not safe, I won´t do it that way. The other one you mention (using the crankshaft pulley which is bigger) has got to be safer.

But If removing the plugs helps releasing compression, I probably have to do it via camshaft. I just can´t remove the belt cover, It looks like the vibration shock/damper doesn´t help getting it out.
Do I have to remove the shock/damper?
Or maybe rotating the engine, by removing the sparks and using the crankshaft bolt. Once it´s so hardly torqued , maybe it will move the whole engine If I try to torque it (clockwhise).

It seems hard to reach the crankshat pulley... The camshaft is far easier to reach.

I have to buy the tool to rotate the engine, as I don´t have one. Confused

My pump is really leaking a bit in the IQ seal and shaft. My A6 is 6-speed manual, and I´m enjoying it !! Smile

Newbie Joined: Jan 20, 2009 Posts: 5

You can slide out the top half of the camshaft pulley cover without taking off the belt tensioner. As you slide the cover up, it fouls slightly on a right angled edge midway on the front of the cover. The cover will flex enough to allow you to pull it forward, away and past it. Works on the engine in situ and worked fine on my spare engine too... When replacing it you need to watch the plastic locating key on the top edge locates properly. It's just under the tensioner.

HTH

Needs to get out more Joined: May 03, 2011 Posts: 119

Actually, I lift the 2 holding metal pieces and pulled it left-diagonally up and it came. It came untill it stopped, and I tried to take it off but seemed to be locking somewhere.

I have to check it again.

The thing is that I´m not sure If I can reach the crankshaft pulley without taking more things out. I just want to rotate the engine so slightly, butit seems that using the camhaft pulley is dangerous, even If I take the sparks out to release compression. Rolling Eyes

Can a torque wrench be used to rotate it? OR I have to use that pulley specific tool with 2 arms to do so?

Posted: Sat May 07, 2011 5:19 pm

So rotate the engine by lifting one front wheel off the ground, engaging 6th gear and turning the wheel.....

Nick

Posted: Sat May 07, 2011 6:08 pm

I've edited my previous post with link which was wrong, but the key image is this one..

So use the wheel turning to get it so far then a small pry bar in this gap on the bell housing under the pump to turn engine over slowly in small amounts..

Needs to get out more Joined: May 03, 2011 Posts: 119

I found that near the gearbox. Am I correct ? Can I use a Screwdriver ? Maybe a bar is stronger Wink

And... good suggestion too. I can always lift the car and turn the whell... in 5ºth or 6th (even easier) I think one wheel is enough, isn´t it ?
So... I think all i have to do now is wait for the seals to arrive.

I tried to set the timing today, but the pump is very torqued and I was affraid to mess it. I will go to a Diesel garage somewhere near. I think they can set it easily.

Posted: Sun May 08, 2011 11:01 am

Not as easy as you'd think unfortunately - the dual-mass flywheel effectively adds a giant spring between gearbox and engine, you can probably turn the engine over using the lift-a-wheel method, but don't think you can get the position exact that way, small movements will simply flex the spring in the flywheel.

Needs to get out more Joined: May 03, 2011 Posts: 119

Didn´t remember that. the DMF will make it less direct . I can always try... until I get the desired injection pump position. Can´t be that hard to put the pump " on cam " ....

Without this I can´t replace that O-ring. And when I do it, I´ll do it for the 3 main seals, which include this O-ring.

Needs to get out more Joined: May 03, 2011 Posts: 119

Just set the timing to correct (I think), specs.

From the 4 bolts holding the pump, the allen bolt was a pain to de-torque, as there is so little space, so I used a thin tool behind the pump.

I have to relief all the fuel lines in both engine and pump sides, so the pump would move and not force any of the lines.

The pump was advanced about 2 or 2,5mm ! The pump mark is at the very centre of the factory marks now. I even tried putting the pump near the maximum advance point. The engine worked, but the sound was not good and looked like failing in some fractions of second sometimes, so I put it back where it was.

The car now starts 1st time cold or warm. Less white smoke.

I did the TDI-Timing test on vag-com with 1200rpm setting (that´s the point it idles while doing the test) and there wasn´t the horrible smoke and engine shaking anymore. I guess that happened before because it was so retarded...

The thing is that the timing test shows the pump is still a little retarderd value 34), but while checking "measuring blocks", the requested timing and the actual timing being read are the same which means the timing is the same as the ECU requested timing.

Maybe the engine was not hot enough ? Around 65º cooling liquid or so...

Any suggestions? I know that if it´s not broken we shouldn´ mess with it, but just wanted it to be perfect !
Stop the leaking is the next step.