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Re: Grinding noise above 2800 rpm



Glenn Merrell wrote:

> Hello Gerry,
>         Welcome to the list.  Without hearing the grinding noise in
> person, I've got to
> first ask some more questions:
> -  Does the grinding noise occur with the engine in park/neutral and
> reving the
> engine?
> -  Does the grinding noise occour only when accelerating in gear
>         -under hard acceleration?
>         -all the time any acceleration?
> -  Does the grinding noise occur more in relation to RPM or to car
> speed?
>
> Answers here will isolate it to engine or driveline.
>
> If engine, that is grinds in neutral or park, then there is something
> going on
> in the engine area, but the torque converter spins in neutral and Park
> too.  But
> it could be a pulley noise, or internal.
>
> If you suspect the torque converter making the noise, they do come
> apart or
> loosen up when abused, turbine blades do shift and bend/crack, and is
> a likely
> cause.  A nationally recognized auto transmission shop will be able to
> easily
> tell you if that is the problem, and may Diagnose it for free.  I had
> AAMCO do
> my '70 Mercedes 250 transmission with a lifetime warranty when the
> first gear
> band snapped, ran it for another 160,000 with no problems, except a
> gasket leak
> that they fixed for free.  BW automatics are no different than most
> other auto
> boxes in design and theory, use a specialist and get the lifetime
> guarantee if
> that turns out to be the problem.  Have it diagnosed before you pull
> the
> engine.  Then you can negotiate a lower cost if you carry in the
> tranny after
> pulling engine/tranny.
>         But I want to make sure it is not something a bit simpler like
> a bad drive
> shaft u-joint, transmission final drive bearing, differential pinion
> bearing, or
> a bad wheel bearing or axle u-joint.  Driveline noises can propagate
> throughout
> the drive line and resonate a remote part, making you think the
> problem is in a
> different location than the apparent sound.
>
> As to inspect for crank bearing wear, it depends whether you enjoy
> crawling
> around for hours under your car, in winter, on a cold floor or
> driveway.  The
> engine does come out very easily if you have a shop hoist of some type
> and a
> device to tilt the engine/tranny as it is coming out of the engine
> bay.  My
> engine was out in 2 hours with a shop hoist on casters, one person,
> and a
> tilting device mounted on the boom hook.  The problem with dropping
> the
> crossmember and steering rack is that some of the bolts are in some
> tight spaces
> where you are likely to bust a knuckle, and the inside onesare tough
> to locate
> if things are covered with crud..  If you are considering engine work
> anyway,
> the engine will be out if you pull it to check.  Just be prepared for
> more cost
> when you open up the engine, it is one of those "well, while I've got
> it out and
> apart, I may as well ...".
>
>         Bushings and shocks are going to be a matter of personal
> preference.  I like
> Koni's, but you need to unbolt them to make an adjustment, no problem
> on the
> rear, but the struts are a bit of a pain.  That is why people
> recommend Spax, as
> they are adjustable on the car, plus they are gas filled wjich keeps a
> downward
> force on the suspension.  Poly bushes are harder and less forgiving
> than the
> replacement rubber type and will stiffen your ride a bit, transmitting
> more road
> noise.  Your choice and preference for the trade off of tighter
> handling and
> more road feel from standard, which is not bad.
>
> Good luck.
>
> Regards,
> Glenn  Merrell
> Triumph Stag Register USA VP
> *******************************************************************
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   Hi Glenn,
Sorry for taking so long to respond but it is winter here and I've put
my Stag away!
Yesterday I had the chance to start it up and do a few tests. To my
disappointment, the grinding noise occurs in neutral, park and
acceleration and since the last time I drove it,  it now starts at just
over 2000rpm!! So, it seems to be getting worse!
The noise is more in relation to rpm. With the hood open I tried to
isolate the noise by manually revving the engine and it definitely is
coming from the lower part!
I have finally decided to pull the engine out the weekend of the 12th.
Now, if only I could find a manual o/d tranny and necessary parts to
replace the BW35....
but that's for another day!
Anyway, thanks for all the support and advice that came in. It's great
to be a part of such a caring Stag-bitten bunch!

Regards,
Gerry Djerrahian, 73 Stag





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