tappy noise that i could do with some help or knowledge

[fuller0554]

Hello everyone, iv had my volvo 850 tdi for a couple of years now and i love it, its what i wanted for ages... Red auto estate, full leather in great condition with full documented 71k on the clock but since iv had the car its had this tap tap tap (which now pushing me over the edge with annoyance, especially when parked by a wall or in the drive through cause it sounds auful has gotten slightly louder over time which i assumed straight away was tappets and a while ago i looked everywhere for the usual quick fixes online etc but its never made a difference. Now ive come accross some forum info that it could actually be the vacuum pump and what makes me think it could be this is it does faid and some time go away wen the brake is pumped. Iv looked at the prices and for 59.99 to my door is a small price to pay for a nice smooth running grunty car with no bloody ticking.
So what are your thoughts, do u think im onto something.
Ps. I posted about this problem ages ago so i apologise for starting a new post with the same issue.
Many thanks

[klunk]

Take the vacuum pump off, Take the diaphragm housing off and clean the oil out, I read from Pierburg that the pumps ideally should be mounted pointing upwards so any oil getting past the diaphragm can drain off, Audi mounted the pump facing down most probably due to clearence issues. The tapping is apparently the accumulation of oil getting past the diaphragm and stopping the piston working to the full extent of its travel, Do this before you spend £££ on a new one only to eventually end up with the same noise! Its the next job to do on mine!

[martin_r_smith]

Exactly what he said ▲▲▲

[fuller0554]

So if i take it off give it a good clean and put it back on but upside down to how it is now it will clear the oil better preventing the ticking coming back.
Many thanks

[fuller0554]

Martin-r-smith, how did u fit an mbc to your tdi if it has an internal waste gate i thought it couldnt be used. I lookd at fitting one to mine when i chid it and do some other stuff but found that all talk of it being done was only to turbos that have been upgraded with an external waste gate. Any info on this would be great bud if you dont mind. Cheers

[klunk]

Originally Posted by fuller0554

So if i take it off give it a good clean and put it back on but upside down to how it is now it will clear the oil better preventing the ticking coming back.
Many thanks

The vacuum pump can only go back on 1 way which is pointing down! Its just a case of removing and cleaning it when it starts getting noisy again.

[henk k]

no reason for needing an external wastegate, they still do the same job. An MBC is typically just put inline with the small boost pipe going into the wategate actuator. Would be a good idea to run a boost gauge though I'd imagine, to prevent overboosting

Edit

This is what you'll see if to look behind the engine. i have to sit onto of it
the white 'circle' shows where the boost pipe goes into the wastegate actuator
This goes up to the valves and stuff behind the airbox, should be labelled in red

[Luxobarge]

There are a couple of threads about repairing noisy pumps in the "Articles" section of this forum.

Here:

http://www.volvoforums.org.uk/showthread.php?t=94961

and here:

http://www.volvoforums.org.uk/showthread.php?t=75954

Cheers

[martin_r_smith]

Henk, fitting it on that pipe won't do squat, well it will lower boost pressure. That pipe comes from the boost control solenoid and is there to increase boost by putting pressure against the wastegate diaphragm stopping it from opening. Without this the wastegate opens at about 7psi. To fit a mbc to these you have to cut the steel pipe that goes from the compressor housing to the side of the wastegate and using 4-5mm silicone hose fit the mbc in between.

And yes a guage is essential! Although it should hit boost cut before major damage is done you just never know. Now I've said this many times but its very important, do not increase the boost pressure without first increasing the amount of diesel you are injecting. Unlike a petrol turbo just upping the boost will not automatically increase the amount of fuel, you have to manually do this by way chip, plugin box or bigger nozzles. If you do just increase the boost you will get no extra power at all but you will melt something!

A simple way to judge it (not the most accurate) is to go by the smoke produced at WOT, if its smokey up the boost a little, if its really clean back it of a little. A little grey haze is perfect. 18 psi seems completely adequate for the amount of fuel standard nozzles can flow.

[fuller0554]

Thanks for the replys. Do you have any pics or know where i might find some good ones of a mbc set up. I am planning on fitting a chip along with a decat (or de-filter shud i say) and egr blanking but first new oil and filter etc timing belt and fuel pump belt just incase as it will need doing at some point so id rather do it now then i know the extra power is not going to cause any issues with the belts.
What kind of gains shud i achive with the following.
Chip offering around 30-40 bhp
Mbc
Decat
Egr blanking
KnN filter
I know its impossible to give an exact figure but just a rough idea would be nice. I guess around 190+ with my fingers crossed :-).
Also adding strut brace back and front with brake servo suport added to eliminate any bulkhead flexing when braking, i did this to my mk3 supra a few years ago and the difference is unbelievable.