Crank Shaft Nut Removal D5 Auto

[john493]

[QUOTE=AidXC90;2564853]

Originally Posted by DieselDoNicely

OK how to get the nut off without impact driver: (Dont use 1/2 drive tools)

Hi DieselDoNicely, when you say don't use 1/2 inch tools does that mean air impact wrenches too, or just hand tools, and what is the reason for this? It's possible to buy 680Nm to 880Nm air impact wrenches in 1/2inch for a reasonable price so surely they would be up to the job or else they wouldn't sell them? I have an air compressor so I don't want to go down the electric route.

Never had any problems undoing the D5 crankshaft nut using a good half inch impact wrench, although it is tight ! Ideally use a very short hose from your compressor and make sure the compressor does not have a restrictive pressure reducer on the output which will impede flow. (had one on my Clarke Tiger compressor & I removed it.) You need a new nut and also renew the 4 smaller bolts that fix the pulley to the cam belt sprocket, these are angle-tightened if I remember rightly.

[AidXC90]

Thanks for the tip about the compressor flow, John. I only have a 10m long air hose so I'll have to see how I go.
I did find a Draper 3/4" impact wrench for a reasonable price (about £80) which I'll probably end up buying since it's not just a one-use tool.
I can only find a 1/2" 300Nm torque wrench for a "reasonable" price (£100!) but even buying all these tools, plus the Volvo crank holding tool, I can do the A/C clutch job, timing belt/pulleys and serpentine belt/pulleys on my XC90 D5 for less than even an independent charges to do the timing belt job.

[john493]

Out of interest, what are you going to do to the aircon clutch ?

[AidXC90]

Originally Posted by john493

Out of interest, what are you going to do to the aircon clutch ?

Hi John, the short answer is that I'm replacing it because it snapped off. If you want the long sob story it's in the XC90 1st Generation Tech section - see link below.
I'm due to update the thread as I've done more investigative work but I asked about the crankshaft nut in this section of the forum because I'm doing the timing belt and serpentine belt at the same time as the A/C clutch work.

https://www.volvoforums.org.uk/showthread.php?t=299330

[john493]

Originally Posted by AidXC90

Hi John, the short answer is that I'm replacing it because it snapped off. If you want the long sob story it's in the XC90 1st Generation Tech section - see link below.
I'm due to update the thread as I've done more investigative work but I asked about the crankshaft nut in this section of the forum because I'm doing the timing belt and serpentine belt at the same time as the A/C clutch work.

https://www.volvoforums.org.uk/showthread.php?t=299330

OK, worth noting there appear to be various different aircon compressors out there, my 2007 V70 2.4D has Volvo part no P30761388, the refrigerant pipes connect to the rear face of the compressor. The clutch has a raised boss that sits proud of the pulley. Access to the a/c clutch is very limited, I guess it may be possible to improve access by unbolting the compressor from the engine whilst leaving the refrigerant pipes connected but this could be tricky.

[john493]

I've just bought a second-hand compressor off eBay - P30761388 - sold as faulty clutch - I'll be stripping it to investigate ! Will post some pics up.

[AidXC90]

Thanks John,
It might be better to post your findings in a A/C thread on the forum to make it easier for people to find in the future as this thread started off being about the crankshaft nut removal.
I'll upload my pictures on my XC90 A/C clutch thread, too.
I agree that access is tricky and I had already unbolted the compressor and tilted it upwards to improve access while leaving the hoses connected.

[petey]

Originally Posted by barrybritcher

why is the diesel centre nut twice the torque of the petrol nut? bizarre

The pulley is not just a device to rotate ancillary devices such as a water pump, it is also a very much needed torsional vibration damper and as such, it's a gert big mass bolted on with an appropriate tightness. The diesel needs a bigger pulley and biggerer torques because the torsional vibration is so very much bigger.

As an aside, I happen to have a Fisker in at work at the mo, and this uses a petrol engine to power a generator to drive the electric motors. As the steering is electric and the 12V charging system comes from the DC-DC converter, there's no need for any pulleys to be driven off of the crankshaft pulley. But it still needs the pulley, for torsional damping reasons and of course to hold the timing belt in place too. It just looks odd all covered in rust....

[Clan]

Originally Posted by barrybritcher

why is the diesel centre nut twice the torque of the petrol nut? bizarre

You need to understand diesels , when the engine is idling the crank pulley is not rotating at a constant speed , with every compression and power stroke it decelerates and accelerates with tremendous force several times per rev , so it rotates in a series of strong jerks , that is why everything is robust on a diesel . It does smooth out a bit when using higher rpm but the lower the speed of the engine the heavier these jerks are ...

[barrybritcher]

very interesting