I was experiencing a lot of engine noise between 2700 and 3000 rpm. I replaced the motor mounts,the center support bearing and the front wheel bearings (wheel bearings made no difference) 5k miles ago and the engine noise impoved. It was still loudest in the same rpm range. But, at 3000 and above the roaring went away the engine sound was quite acceptable. I never can hear the normal turbo whine above the roar of the engine. Now it is back worse than before and not nearly as quiet above 3000 rpm. The fan clutch does not change speed much when I rev the engine and spins about 7 revolutions after I shut off the engine when hot. The exhaust system is new and I cannot feel any leaks. I have checked for leaks on the intake side of the turbo. Air filter is also new. The EGR and the air recirculating valve are disconnected. I blanked off the EGR.
I'm stumped. It is no fun driving the car when it is this loud. My brothers F350Powerstroke is quieter and sounds better.
Any ideas?

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1987 300D 146K Original #14 Head
One eye on the road, the other on the temp. gauge

Gone But Not Forgotten
1983 380 SEL Long gone
1983 300SD Wish I hadn't traded it in on a 90' Corvette
1989 300SE My all time favorite
1995 E420 Went like a bullet

Your car is louder than a Powerstroke? Something is definitely wrong. Could you describe the noise more, or better yet, post a recording of it. I'm wondering if it could be something other than the engine.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

I agree with Skippy, not right.

Look at the exhaust, see if it is touching the body or something else.

Also as the peanut-butter guy says; what kind of sound? From were does it eminate (floor, footwell, dash, outside the car, etc.)? Is it lounder or softer when accelerating? Revving in neutral?

More information will help a great deal.

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Gone to the dark side

- Jeff

I thought so too. If I am cruising anywhere between 2700 and 3000 rpm let off the throttle and put the car in neutral, the car is silent. Run the rpm's up to 3000 while in neutral, same roar. So, not tranny or wheel bearing. Is it possible for the turbo to be the problem? I never can hear the turbo over the roar of the engine. It sounds like riding next to a large gas engine delivery truck. Even in my neighborhood, driving under 30 mph, if I accelerate over 2000 rpm I hear the same roar, just not as loud. I used to own an 83 300 SD, it never made this much noise. I know this car is not going to be as quiet as my 95 E420, but something is not right.
I'm not sure how to record the noise level in the cabin?

__________________
1987 300D 146K Original #14 Head
One eye on the road, the other on the temp. gauge

Gone But Not Forgotten
1983 380 SEL Long gone
1983 300SD Wish I hadn't traded it in on a 90' Corvette
1989 300SE My all time favorite
1995 E420 Went like a bullet

could it be a resonance from a bad center muffler?

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Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (113k)
1991 350SD (206k)
1991 300D (228k)
1993 300SD (291k)
1993 300D 2.5T (338k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (265k)

Past Diesels:
1983 300D (228K)
1985 300D (233K)

My 240D got pretty loud under power when the exhaust manifold cracked, but was no louder than normal at idle. I'm also wondering if your exhaust system is making contact with the body through something other than the exhaust hangers. This can make quite a racket.

__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

It's hard to tell if you're describing a fan roar or vibration roar.

I would consider removing the belt for a quick test, rev to 3000rpm and see if the noise is gone (very short test so you don't toast the head!!!).

The car being in/out of gear changes the position of the engine and exhaust slightly (exhaust is bolted to the transmission). Still, check all parts of the exhaust for contact with the body.

Does it shake at all?

Perhaps one of your new engine mounts is a dud and collapsed already.

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Gone to the dark side

- Jeff

When I got this car someone had incorrectly installed the exhaust hanger that attaches to the tranny and it cracked the belly pan. I turned it around so it fit in the slot and repaired the pan with fiberglas resin and cloth. I can remove the bracket without the exhaust touching any part of the body. I checked the entire exhaust for contact anywhere, none. I will remove the hanger and drive the car. I will try anything.

__________________
1987 300D 146K Original #14 Head
One eye on the road, the other on the temp. gauge

Gone But Not Forgotten
1983 380 SEL Long gone
1983 300SD Wish I hadn't traded it in on a 90' Corvette
1989 300SE My all time favorite
1995 E420 Went like a bullet

No need to. Is the hanger or anything touching the belly pan?
What about exhaust. Do you smell it while driving? See any traces of soot around the exhaust manifold, turbo, or exhaust system?

__________________

Gone to the dark side

- Jeff

I have not seen anything touching the belly pan, but I will check the hanger again. I disconnected the exhaust system at the exhaust manifold for better access to the right side motor mount. When I reconnected it, the car was still quieter than it is now, I looked at the exhaust manifold and around the turbo, I don't see any soot. What if I took the belly pan off and drove it?
Thanks for all the suggestions. I know it's difficult to diagnose noises from long distance.

__________________
1987 300D 146K Original #14 Head
One eye on the road, the other on the temp. gauge

Gone But Not Forgotten
1983 380 SEL Long gone
1983 300SD Wish I hadn't traded it in on a 90' Corvette
1989 300SE My all time favorite
1995 E420 Went like a bullet

After listening carefully to this noise and realizing that now it is loud at the same rpm it used to be quiet and is quieter at an rpm when it used to be noisy, I beleive as others have said, that a motor mount has failed or the mount bolts are loose. I will check the top and bottom bolts this weekend. The motor mounts have less than 5K miles on them and are Lemforder. Does anyone know what kind of warranty these mounts should have? And is there a better brand?

__________________
1987 300D 146K Original #14 Head
One eye on the road, the other on the temp. gauge

Gone But Not Forgotten
1983 380 SEL Long gone
1983 300SD Wish I hadn't traded it in on a 90' Corvette
1989 300SE My all time favorite
1995 E420 Went like a bullet