Engine: 70: Auxiliary / Serpentine Belt Slipping Off

[damageandy]

If the bottom pulley is not inline with the other then this is the problem.
Dont start the car until it is fixed or you could take the cambelt out.

Either the pulley has come unbonded or the bolt is ready to fall out.

Cambelt is easy on these, bottom pulley needs doing anyway so thats half the job.

[BritInSweden]

I appreciate the comments! I was beginning to think I was only one in the world that had this problem as all I can find when googling is what a bas"*rd the main nut is to get off. So no driving and topped up the ps fluid.

I've not been able to get out to take the wheel off due to weather but took another pic here. This is looking straight down into the engine from above. Nearest pulley with grooves in the shadow bottom of pic is power steering, then the black wheel is aux tensioner pulley and furthest away at bottom of engine is crankshaft pulley which you can see is at least a couple of mm out to the left.

I am borrowing an air ratchet wrench this week from a neighbour to see if I can get the bolts off and might as well order the timing belt idlers etc too and try to get as far with it as I can. Will update when the weather clears a bit. No fun doing this in a snow storm but at least there's no worries getting parts up here in Sweden.

[BritInSweden]

Hi all. I got stuck with this job due to bad weather but today managed to get out for a bit. Took the front wheel off to look around and tried to loosen the big crankshaft pulley wheel nut just using my socket set just to see if it would budge. It did, the problem is it moved everything on it, the timing belt and all the cogs in unison.

I realised I had removed the aux belt before doing this so have I done something stupid here or can I just put the aux belt back on and try to loosen the nut again or is this free moving crank pulley a symptom of the problem I have? Most people on YouTube and here etc seem to be able to remove this nut without using the special fastening tool to hold the harmonic balancer in place and only use the tool when tightening back up to the correct 300nm.

I have attached a couple of photos. The white timing mark was there already. There is also a tiny notch / mark on the wheel 3/4mm to the left of the white mark, is this the actual mark I should be using or safe to assume the white mark is correct?

Also does anyone know if there any reason why I shouldn't attempt to change the crank pulley wheel and timing belt kit in cold temperatures except for my own comfort and sanity? I am hoping to borrow the tools needed including a 500nm plus impact driver but looking at weeks of minus temperatures ahead of me, no access to a garage and an increasingly impatient family waiting for their car to be fixed

[oragex]

I doubt you will be able to break loose the big nut with hand tools, even with a long pry bar. That nut is crazy tight and the rust adds even more to it. Now, I'm not sure if it's safe to drive the car like this, in the first place. If you think it's safe and the pulley won't start slipping (because it's already in a weird position and we don't know why), the best would be to drive to a garage, ask them to undo with impact, tighten it down as much as you can with your tools (should be quite tight, maybe 150 lbs or more), and drive back home very gently on the pedal - but see what the others have to say because the diesel engine is quite torquey so not sure how safe it is not to have the nut with the full torque on it. With a full battery, you should be able to drive a decent 10-15 miles, maybe remove the headlights fuse to save some power - of course no P/S
You can install a timing belt in cold weather, the tensioner indicator will need adjusted for the colder temperature. Volvo has this diagram, judging by it, for a 0C temperature, you may want the needle to be perhaps just reaching the left metal tab (not yet overlapping it). You may check it again next summer but I don't think it's too dramatic if it's not 99,99% at the exact position. https://www.underhoodservice.com/wp-...0000015777.gif

[reggit]

What does the bottom pulley look like from underneath with the plastic shroud removed?

If you’ve got a competent garage nearby, I’d be tempted to get it recovered to them to repair if you don’t have the means to undo that bottom nut, 300ft/lbs I think (don’t know the metric)

[BritInSweden]

I forgot to mention this is an auto box D5 and just checked the Haynes manual which says I should take off the aux belt first and rotate the crank pulley to line up the timing markings anyway so phew.

I can borrow an impact driver up to 700nm plus torque wrench to 350nm and don't want to risk moving the car so willing to fight this one to the bitter end (or ring a mobile mechanic).

Crank pulley wheel looks rusty but nothing sticks out as strange and doesn't move laterally to my untrained eye. I can post a pic in a day or two.

To prevent the crank pulley turning whilst taking off the main nut Hayes suggests (for the auto models) to take out the starter motor and use a flat bladed screwdriver "wedged between the driveplate ring gear teeth and the transmission housing". No pics or more info than that so pretty novice unfriendly. The reassemble is the reverse. I am hoping the driveplate will make itself known when I take off the starter motor as a quick google search didn't come up with much.

Haynes don't mention any special tool to keep the crank pulley from spinning while tightening & loosening the nut and a large flat head screwdriver is something I do have so going to go the Haynes route for now. Any tips on how to do it this way on an auto would be great. I will keep chipping away at it when the weather allows and post anything that might help others. I'm getting used to using shanks's pony and a sledge to do the food shopping

[oragex]

The starter can get stuck from corrosion and crack if hit to dislodge. Go gently with a cold chisel around. There is a video somewhere on yt showing the belt replacement with blocking the flywheel. Not sure if a screwdriver will be enough, the video was using something like a thick stud

[wynnj]

If you've got a 700nm torque gun you may not need to block the crank. The inertia of the engine's internals may be sufficient to stop it turning too far before the nut undoes.
If not the correct tool isn't very expensive- see
https://www.ebay.co.uk/itm/Volvo-Pet...UAAOSwVFlUGI3m
https://www.ebay.co.uk/itm/New-TOOLS...8AAOxysstSZUD8 or try volvo themselves, I think I read that the volvo part isn't too expensive either.
You will need to block the crank to re-tighten the nut and the correct tool is much better and safer than removing the starter and risking damaging the flywheel or bell housing.
Once you've undone the nut don't forget to realign all the marks before removing the crankshaft pulley and cam belt.

[Willow place]

All you have to do is look at Cheshire's video , very simple !

[damageandy]

700nm impact gun should bang it off without needing to lock the engine.

Its only hard to get off because people don't want to spend out on the right tool for the job. If you have a proper impact gun or appropriate size breaker bar and locking tool its literally a 5 second job.

They make a special tool for locking it.

Take a close up picture of the bottom pulley so we can see why its not in line anymore.