How To test the Diesel High-Pressure system - Page 3

john493 · 24th May 2015, 18:53

Thanks Mike I'll try it.

john493 · 1st June 2015, 21:41

I'm hoping to do the leak off test tomorrow, weather permitting.
I'm also on the UK Volvo forum & found this link to clean the injectors by running the engine on neat cleaner - any views on whether this is feasible on my 75 CDTi ? If so, where would be the best place to connect the pipes ? https://www.youtube.com/watch?v=xYsXHC2-PSw

FrenchMike · 2nd June 2015, 06:43

Quote:

Originally Posted by john493

I'm hoping to do the leak off test tomorrow, weather permitting.
I'm also on the UK Volvo forum & found this link to clean the injectors by running the engine on neat cleaner - any views on whether this is feasible on my 75 CDTi ? If so, where would be the best place to connect the pipes ? https://www.youtube.com/watch?v=xYsXHC2-PSw

A guess your 2002 car has accumulated lot of miles and so a simple cleaning won't help ...

john493 · 2nd June 2015, 13:48

Completed the leak off test today(thanks Mike for the instructions), ran the engine for 2 minutes, the black line on the jars is 20ml.
So it looks like I've got a fairly leaky set of injectors, with no. 3 leaking about 30ml in 2 mins, the others on the limit at 20ml approx.

I'm guessing I need to take the injectors out for reconditioning - I know I've got to remove the inlet manifold first - are the injectors likely to come straight out, or is a puller needed ?

FrenchMike · 2nd June 2015, 14:19

Quote:

Originally Posted by john493

Completed the leak off test today(thanks Mike for the instructions), ran the engine for 2 minutes, the black line on the jars is 20ml.
So it looks like I've got a fairly leaky set of injectors, with no. 3 leaking about 30ml in 2 mins, the others on the limit at 20ml approx.

I'm guessing I need to take the injectors out for reconditioning - I know I've got to remove the inlet manifold first - are the injectors likely to come straight out, or is a puller needed ?

Well,at least number 3 is faulty ...

Lot of threads about it ,for instance :

an old one from "blackadder"

I removed my injectors with ease after 120,000 miles in place.

Dump plenty penetrating oil ou vinaigre into the injector wells and run the car for a week or so to give it time to work its way down the wells.

When removing the injectors, follow the procedure above or Haynes, that's OK, but remove the 2 small nuts holding each injector clamp LEAVING THE STUDS IN PLACE. Do not try to remove these studs it will cost you.

You can try the blow-out method described above, no probs.

If one sticks, remember the injectors should be free to rotate a little in their now loosened clamps without damaging the studs, so they can be freed by putting a piece of pine wood against the injector's threaded fuel inlet nozzle and tapping one way then the other with a hammer to rotate the injector a few degrees.
Rotation of the injector is then clearly seen and this tells you it is freed off.

Then use a large blade screwdriver to lever gently upwards on the underside of the fuel inlet nozzle, again protect the thread with a sliver of soft wood. Injector should now just pop out.

WARNING
If any injector will not rotate, even using a heavier sideways knock, its probable that you will have to damage the injector to remove it or leave it to a trusted Garage.
Plenty of threads you can find on trouble with injectors.

Good luck

Mike

john493 · 7th June 2015, 12:23

Well, I ran the engine on 1 litre of liquid moly diesel purge - I unplugged the in-tank pump and connected the diesel purge container to the input of the under-bonnet pump - it seemed to work ok - I stopped the engine to top up the container, then the car would not re-start - the UB pump did not run, though power was present - a quick tap with the end of a screwdriver and the pump started - so that's my problem - I've ordered a new pump.
(also tested the in-tank pump which delivers fuel OK for about 15 secs at the input pipe to the UB pump once ignition turned on)

FrenchMike · 7th June 2015, 12:38

Quote:

Originally Posted by john493

Well, I ran the engine on 1 litre of liquid moly diesel purge - I unplugged the in-tank pump and connected the diesel purge container to the input of the under-bonnet pump - it seemed to work ok - I stopped the engine to top up the container, then the car would not re-start - the UB pump did not run, though power was present - a quick tap with the end of a screwdriver and the pump started - so that's my problem - I've ordered a new pump.
(also tested the in-tank pump which delivers fuel OK for about 15 secs at the input pipe to the UB pump once ignition turned on)

That's clear ,you UBP is dead ...may be ,you could forget injectors for the moment
So my LP test must show much less than 3.9 volts !

bladerunner · 1st April 2016, 14:58

so, after having a cold starting problem I've read through this and I think my in tank pump might have failed,I cant hear it buzzing at all now. its only been in a couple of years as well. symptoms are poor cold starting, ub pump seems noisy and also seems to pump for a long time after ignition on and I've just done the voltage test on the fuel pressure switch and with the ignition on I get 1.6 volts, start the car and it jumps up to 3.8 volts then switch engine off and the voltage slowly drops back to 1.6 volts.would I be correct in my assumption about the pump?

FrenchMike · 1st April 2016, 17:13

Quote:

Originally Posted by bladerunner

so, after having a cold starting problem I've read through this and I think my in tank pump might have failed,I cant hear it buzzing at all now. its only been in a couple of years as well. symptoms are poor cold starting, ub pump seems noisy and also seems to pump for a long time after ignition on and I've just done the voltage test on the fuel pressure switch and with the ignition on I get 1.6 volts, start the car and it jumps up to 3.8 volts then switch engine off and the voltage slowly drops back to 1.6 volts.would I be correct in my assumption about the pump?

You may have an intermittent issue with one pump or the other ?
As long as you get 3.8 volt ,the pressure is sufficient to feed the HP pump.

At 2.5 volt = 1.7 bars you enter in emergency mode

What about the HP sensor value ? (measure preferably while cold)

If too low,see HP regulator O ring or injector leak....

bladerunner · 1st April 2016, 19:20

I'm going to have a better look at it tomorrow. I know its not very scientific but I disconnected the fuel pipe into the filter and switched the ignition on to see what the fuel flow was like and the jet of fuel didn't even get past the radiator grill. I would have thought it would have shot 5 or 6 feet at least.

24th May 2015, 18:53	#21
john493 Avid contributor 75 Tourer CDT Join Date: Apr 2014 Location: Bloxham, N. Oxon Posts: 139 Thanks: 60 Thanked 10 Times in 10 Posts	Thanks Mike I'll try it. __________________ 2003/53 CDTi Conn Tourer

1st June 2015, 21:41	#22
john493 Avid contributor 75 Tourer CDT Join Date: Apr 2014 Location: Bloxham, N. Oxon Posts: 139 Thanks: 60 Thanked 10 Times in 10 Posts	I'm hoping to do the leak off test tomorrow, weather permitting. I'm also on the UK Volvo forum & found this link to clean the injectors by running the engine on neat cleaner - any views on whether this is feasible on my 75 CDTi ? If so, where would be the best place to connect the pipes ? https://www.youtube.com/watch?v=xYsXHC2-PSw __________________ 2003/53 CDTi Conn Tourer

7th June 2015, 12:23	#26
john493 Avid contributor 75 Tourer CDT Join Date: Apr 2014 Location: Bloxham, N. Oxon Posts: 139 Thanks: 60 Thanked 10 Times in 10 Posts	Well, I ran the engine on 1 litre of liquid moly diesel purge - I unplugged the in-tank pump and connected the diesel purge container to the input of the under-bonnet pump - it seemed to work ok - I stopped the engine to top up the container, then the car would not re-start - the UB pump did not run, though power was present - a quick tap with the end of a screwdriver and the pump started - so that's my problem - I've ordered a new pump. (also tested the in-tank pump which delivers fuel OK for about 15 secs at the input pipe to the UB pump once ignition turned on) __________________ 2003/53 CDTi Conn Tourer

1st April 2016, 14:58	#28
bladerunner Regular poster 75cdt connie se and Yamaha R1 Join Date: Nov 2010 Location: Sheffield Posts: 49 Thanks: 0 Thanked 3 Times in 3 Posts	so, after having a cold starting problem I've read through this and I think my in tank pump might have failed,I cant hear it buzzing at all now. its only been in a couple of years as well. symptoms are poor cold starting, ub pump seems noisy and also seems to pump for a long time after ignition on and I've just done the voltage test on the fuel pressure switch and with the ignition on I get 1.6 volts, start the car and it jumps up to 3.8 volts then switch engine off and the voltage slowly drops back to 1.6 volts.would I be correct in my assumption about the pump?

1st April 2016, 19:20	#30
bladerunner Regular poster 75cdt connie se and Yamaha R1 Join Date: Nov 2010 Location: Sheffield Posts: 49 Thanks: 0 Thanked 3 Times in 3 Posts	I'm going to have a better look at it tomorrow. I know its not very scientific but I disconnected the fuel pipe into the filter and switched the ignition on to see what the fuel flow was like and the jet of fuel didn't even get past the radiator grill. I would have thought it would have shot 5 or 6 feet at least.