Symptom:Very loud whining whirring noises from timing
chain area of 1995 Saab 9000 turbo automatic.At
first,noise seemed to be coming from auto
box,(yeah…really),so I pulled the
transmission.Stripped,cut open convertor,no problems.Ran
engine with box out of car,and noise is still there,but
less severe.It seems with the box on,the resonances from
the flex plate are worse.Box is now back in car.
Pulled cam cover,and,as far as I can tell,timing chain
is OK.Probably it’s balance shaft chain.Car is UK 2
litre.Definitely has balance shafts..
What’s the easiest way of pulling the timing cover? I
don’t want to remove the head if possible,already spent
way too long on this job.Can I drop the sump a bit,and
wangle it out,with the head still on?
Thanks 
–
Best Regards,
Chris Wilson
http://www.maximum-bhp.u-net.com
- Hide quoted text — Show quoted text -
Chris Wilson wrote:
> Symptom:Very loud whining whirring noises from timing
> chain area of 1995 Saab 9000 turbo automatic.At
> first,noise seemed to be coming from auto
> box,(yeah…really),so I pulled the
> transmission.Stripped,cut open convertor,no problems.Ran
> engine with box out of car,and noise is still there,but
> less severe.It seems with the box on,the resonances from
> the flex plate are worse.Box is now back in car.
> Pulled cam cover,and,as far as I can tell,timing chain
> is OK.Probably it’s balance shaft chain.Car is UK 2
> litre.Definitely has balance shafts..
> What’s the easiest way of pulling the timing cover? I
> don’t want to remove the head if possible,already spent
> way too long on this job.Can I drop the sump a bit,and
> wangle it out,with the head still on?
> Thanks
> —
> Best Regards,
> Chris Wilson
> http://www.maximum-bhp.u-net.com
Chris , never done this job myself so can’t help much , but I remember
my local saab agent telling me to be very carefull about tightening the
timing chain cover to head bolts.Apparently even when using the
recommended torque the cover can split , so take it easy !!!
As regards the noise, it’s not the oil pump is it (cavitation ? ).Just a
thought .Best of luck , Tim.
Comment by admin — December 31, 2009 @ 4:47 pm
The oil pan is sealed with only sealant. breaking it in the front may
bring leaks. I have done the job successfully by only removing the
timing cover and applying locTite 518 anaerobic sealer to both the
cover, lower part of head gasket that is exposed when the cover is
removed and the oil pan. Any excess of this sealer will not dry and
plug oil passages. If you have a worn balance chain, chances are the cam
chain is worn as well. There have been reports of gear wear in these
engines, though I have not seen that. When its apart, make sure the
gears are ok. If I had the timing cover off an engine, I would
definitely replace at least both chains.
We overfill the 2.3 engine to the X in MAX on the dipsticks. This
doesn’t cause any aeration, leakage or other problems. Our regular
customers and our own cars do not have timing chain or balance chain
problems as the overfill allows a bit more oil on the chain. Stick with
a factory filter and use 10w30 oil, preferably synthetic, especially in
turbos. Other viscosities don’t work as well and when you go to the ones
with a wider range, like 15-50 or 20-50, the oil is too thick and
contains more additives to bring about the increase in viscosity range.
The additives are what break down and lead to sludge formation and turbo
coking.
Comment by admin — December 31, 2009 @ 4:47 pm
[As well as this reply in alt.autos.saab a copy was also
e-mailed to Ywan Mason ,the cited author.]
In article <3605685C.B86A4…@bellsouth.net>,
yma…@bellsouth.net apparently said in alt.autos.saab
- Hide quoted text — Show quoted text -
> The oil pan is sealed with only sealant. breaking it in the front may
> bring leaks. I have done the job successfully by only removing the
> timing cover and applying locTite 518 anaerobic sealer to both the
> cover, lower part of head gasket that is exposed when the cover is
> removed and the oil pan. Any excess of this sealer will not dry and
> plug oil passages. If you have a worn balance chain, chances are the cam
> chain is worn as well. There have been reports of gear wear in these
> engines, though I have not seen that. When its apart, make sure the
> gears are ok. If I had the timing cover off an engine, I would
> definitely replace at least both chains.
> We overfill the 2.3 engine to the X in MAX on the dipsticks. This
> doesn’t cause any aeration, leakage or other problems. Our regular
> customers and our own cars do not have timing chain or balance chain
> problems as the overfill allows a bit more oil on the chain. Stick with
> a factory filter and use 10w30 oil, preferably synthetic, especially in
> turbos. Other viscosities don’t work as well and when you go to the ones
> with a wider range, like 15-50 or 20-50, the oil is too thick and
> contains more additives to bring about the increase in viscosity range.
> The additives are what break down and lead to sludge formation and turbo
> coking.
OK,thanks for the tips,cover now off,and as you rightly
say,no sump gasket,just the remains of the liquid gasket
used at the factory.Same for the timing cover to block
interface.I’ll get some Loctite as recommended.
Fairly severe wear on the front balance shaft
sprocket,and also on the crank balance shaft drive
sprocket.Will heed the warning and replace cam chain,and
at least the cam crank drive sprocket.
The tensioner guide slipper for the balance shaft chain
is also badly grooved.Not at all impressed at the state
of this area,in what is a genuine 40 K mile car,serviced
by Saab main agents until it came to us a couple of
weeks back.
It came apart pretty easily.Here’s hoping it re
assembles as straightforwardly….Strikes me both cam
and balance shaft chains should be duplex,and maybe one
pitch bigger in size.Especially as Saabs are thought of
as good for high mileages.Hmmm..
Thanks for the info Ywan and Tim.
–
Best Regards,
Chris Wilson
http://www.maximum-bhp.u-net.com
Comment by admin — December 31, 2009 @ 4:47 pm