2003 v70 d5 squeal between 1500 and 2500 revs

lenny · Post by **lenny** » 03 Jan 2015, 22:55

i've had this squeal between 1500 and 2500 revs for a few days now.
i have changed the fan belt, tensioner, and idler pulley and made no difference.
done the clutch check on alternator and all is good.
the noise only occurs under load when driving. rev up stationary and no noise at all.
anyone experienced this before
any info greatly appreciated
regards
lenny

Post by **oragex** » 04 Jan 2015, 08:03

Alternator bearing and the A/C pulley also need to be checked, known to freeze at higher miles. Don't delay, as there were many people who had the accessory belt snapping which in turn took off the timing belt and ruined the engine (happens quite often on the d5).

There is also the tensioner and idler on the timing belt.

For specific diesel questions, you can also have a look at this european forum, where the D5 are commun (the D5 is not sold in the US, unfortunately) http://volvoforums.org.uk/

lenny · Post by **lenny** » 04 Jan 2015, 08:25

thanks for your reply oragex, checked everything you mentioned prior to posting.
car runs superb beginning to think it might be a turbo squeal, do you think i should remove and clean turbo unit, and is it known to squeal
many thanks

Post by **jimmy57** » 04 Jan 2015, 11:00

Squeal can be caused my many things. exhaust leak before turbo since that part is pressurized in the same range as the inlet manifold. Leaks in intercooler or intercooler plumbing (intercooler = charge air cooler).
Turbo could be it but I would not expect turbo caused squeal to subside at 2500 rpm. Turbo caused squeal can be checked by the compressor to compressor housing test. To do this you have to have access to the turbo inlet. Engine off. Use fingers to rotate the compressor fan while at the same time pushing the compressor fan towards the side. Do it in all directions to the side. If the blades can contact sides of housing then the bushings in turbo are worn and the blades could be contacting the sides and making the squeal noise. All turbo noise I have ever heard was what I'd call a screech, not at all the same sound as when you've heard a belt slip on an engine with loose belt as it is revved.
The crankshaft balancer could be it as the load on it is different engine loaded vs free revving. Mark a line across the part bolted to crank to the outer part and then get it to squeal and check to see if the line is still sligned or if the marks have moved apart.

lenny · Post by **lenny** » 05 Jan 2015, 08:27

thanks for that jimmy57
been out today and its been alot warmer so noise was not as loud but still there
leaning towards a bearing again now
if i parked the car in a straight line and took the fanbelt off, would it do any harm to drive it a small distance up the road and see if the noise still appears at 2000 revs. that way i know if its one of the fanbelt pulleys if not i can start looking elsewhere.
regards
lenny

lenny · Post by **lenny** » 11 Jan 2015, 08:34

checked car again today and suspected a vacuum leak.
took the vacuum pipe for the turbo off the air box and hey presto no squeal.
renewed the pipes thinking a pin hole in one and still the same, removed and cleaned turbo control valve and no difference. car still runs superb its just this loud squealing noise.
doing my nut in now
any idea anyone ?