850 tdi Static Fuel Pump Timing/Belt Change

[Purdydog]

Hi all,

Does anyone know of a guide for changing fuel pump timing belt and setting up timing statically ?

I’ve looked around here and seen discussions about it but no clear instructions.
Car runs a bit flat, and idles noisily. I suspect fuel pump timing as it hasn’t been checked for a while and belt is due a change.
Had lots of sharp intakes of breath from local volvo independents and daren’t even contemplate local main dealer!

Is it possible for a competent diyer ?

Cheers in advance

P

[Martin Cox]

Changing the fuel injection pump belt is not too difficult and I'm sure there's a guide somewhere on this forum since I've used one myself. The cambelt is a rather more difficult job but again doable by a competent diyer and you do need some specialist tools or homemade equivalents.

For the injection pump belt, in essence the job entails setting the engine to No 1 cylinder TDC, locking the injection pump; there's a screw built into the pump for the purpose, then removing the belt by slackening the tensioner. Put the new belt on and retension and unlock the pump. Hopefully the timing will have stayed close enough for the engine to start.

However you will need to get the timing set dynamically and this requires the appropriate software. The timing can be adjusted over a small range by adjusting the tensioner and idler. Larger adjustments have to be made by moving the camshaft pulley relative to the camshaft. The timing doesn't need to be out by much to cause all sorts of problems.

I had the local main dealer set the dynamic timing after I sorted out the aftermath of a broken cambelt.

A couple of things to note. Pay particular attention to the condition of the tensioner and idler pulleys; if there's the slightest suspicion over their condition, replace them. I used genuine Volvo parts (branded VW Audi). If there's the slightest question over the the state of the cambelt and tensioner, they should be replaced too.

There are no helpful marks for setting up the timing. if you lose the timing, getting it set sufficiently close to get the engine to run again can involve a lot of trial and error.

There's a good guide to how to do it on YouTube ( https://www.youtube.com/watch?v=IbQThE-PiMA and associated videos ) This is for an S70 but it's the same engine. It's a bit long winded in part but I found it extremely helpful and will give you a very good idea what's involved.

I hope this is of some help. Good luck.

Martin

1998 V70 Tdi auto, 224000 miles

[Martin Cox]

These notes, for which I claim no credit whatsoever, may also be helpful. They have been previously posted on this forum. I cannot recall the original poster and author to credit them.

Since the D5252T engine is an Audi AEL engine with Volvo modifications, an internet search on Audi AEL pump timing may produce some useful results too.

When changing the belts, the usual recommendation is to go for the genuine Volvo parts or Gates. I chose the genuine parts.

Martin

[SwedishBus]

If you have access to the dial gauge adapter and a small dial gauge to go into the back of the fuel injection pump, in order to find the correct timing point to lock the pump shaft at, then it is possible to get very close to the optimum pump-timing by mechanical means only, i.e. Vol-FCR or any of the equivalents is not needed absolutely.

I have set-up a very broken TDI like this from first principles, where there was nothing left timed on the engine (totally wrecked by incompetence in a garage on changing the cambelt previously), and I managed to get the timing of the fuel injection pump within the optimal window of the dynamic timing window first time. It's true that with the dynamic timing feedback you can get the pump-timing spot-on with a further tweak, but manual set-up is possible with care.

A lot of injection pumps of this era (early 1990's Bosch) have a nominal cam "lift" figure to set the timing through the back of the pump (axial to the pump) and this is a very effective way of setting them, even where they have a further drive-pulley timing slot to set them. I cannot remember the figure off the top of my head, but I can get it if you're interested. The DTI (test indicator) adapter and gauge are common enough in many kits.

[Purdydog]

Thanks for taking the time to reply in such detail everyone, I really appreciate it.

I’ll checkout the YouTube link and also google setting up an Audi pump.

Swedishbus, I do have access to a DTI and the means to make an adaptor if necessary.
Any further details would be a great help.

Best Regards

P

[rudi dudi]

Originally Posted by SwedishBus

If you have access to the dial gauge adapter and a small dial gauge to go into the back of the fuel injection pump, in order to find the correct timing point to lock the pump shaft at, then it is possible to get very close to the optimum pump-timing by mechanical means only, i.e. Vol-FCR or any of the equivalents is not needed absolutely.

I have set-up a very broken TDI like this from first principles, where there was nothing left timed on the engine (totally wrecked by incompetence in a garage on changing the cambelt previously), and I managed to get the timing of the fuel injection pump within the optimal window of the dynamic timing window first time. It's true that with the dynamic timing feedback you can get the pump-timing spot-on with a further tweak, but manual set-up is possible with care.

A lot of injection pumps of this era (early 1990's Bosch) have a nominal cam "lift" figure to set the timing through the back of the pump (axial to the pump) and this is a very effective way of setting them, even where they have a further drive-pulley timing slot to set them. I cannot remember the figure off the top of my head, but I can get it if you're interested. The DTI (test indicator) adapter and gauge are common enough in many kits.

Exactly!!! Someone else who speaks common sense.All this dynamic timing crap
and special Volvo software rubbish that gets endlessly repeated on here and other places.
This pump is a Bosch ve pump and Bosch service centres have a good laugh at this Volvo dynamic crap.
Your pump specs for timing is between .53 and .57 lift
Set it to the sweet spot which is .55 for this pump
I can time these with a dti to run sweeter than most Volvo dealers or Volvo specialist could only dream of.
If your still not sure how to do it.. Do yourself a favour and take it to either a Proper Bosch or Delphi diesel service service centre which employs diesel fitters instead of technicians

[Purdydog]

Thanks rudi,

I looked at a few how to videos on you tube.

It doesn’t look too difficult but they all show it being down with the engine out! I guess it’s easier to see / film.
What’s access like for doing this with the engine in situ on the 850?
I’ve found this adapter on flea bay would this be suitable?

https://www.ebay.co.uk/itm/VAG-VW-AU...3-126da46be57e

There is a Bosch service centre (electro-diesel) in Exeter so I may give them a ring to see if they can do it.

[SwedishBus]

I think that adapter looks a bit long. The access with a short adapter into the back of the pump is not bad at all, and I don't remember having to struggle to do the DTI work in-situ on my TDI.

To qualify this, I did have all the injector pipes off at the time, and that was because I was building the engine back up with a secondhand cyclinder head, so it might be you will need to remover cyls. 4 and 5 pipes, but that need not be an issue at all.

Most of the Bosch pumps take a standard thread adapter, as the blanking plug is a common part between makes, so it makes little difference which one you use. The lift-figure is measured from "off-cam" to a nominal lift dimension, so the length of the adapter is unimportant.

If you really get stuck, PM me and I'll post an adapter down to you for loan, as they are not a big item.

[badgered1]

I've just done the same on two engines, that adapter is too long, mine is about 2 1/2" long.

Maybe there are different pumps, but I went with volvo instruction of .25 lift before locking pump on both my engines and they run fine.


Also I understand its better to run these engines for a bit to let the belts settle down before dynamically timing.

[NewbieVV1976]

Hi. If anyone could help me, please. Looking for a code
Volvo radio 353771-1
816
Serial VO1610 X9141466H

Thanks in advance