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Author Topic: sound proofing a vanagon diesel 1.9 na  (Read 5816 times)

August 28, 2011, 06:52:55 pm

paolomarks

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sound proofing a vanagon diesel 1.9 na
« on: August 28, 2011, 06:52:55 pm »
So I''ve got a vanagon with a 1.9 AAZ.  A while a go the turbo went out and I simply removed it, plugged up the turbo oil lines and re routed exhaust and air filter(k&n in drivers side D pillar)  What can be done about the noise!  No tach but with stock diesel tranny in 4th It's bearable untill about 40mph and then a very unpleasant droning/bone rattling vibration increases until about 55 when it's still loud but smooths out a bit. It's definately rpm dependant and will do it in any gear at the same rpm range. I know putting the turbo back in will soak up some of the noise, but i'm satisfied with the power of the NA and like its simplicity.  Things I've done to try and quite things down a bit include. extra carpets over engine compartment (below cushion) , removed wall panels and installed butyl rubber on sheetmetal  and fiberglass insulation...  I havn't tried but have thought about wrapping the exhaust in some kind of heat proof tape,  different motor mounts, different muffler, different manifolds. Possibly some kind of clear plastic partition right in back of rear bench.  I need to quite her down, its driving me mad and is the only complaint I have with her. Let me know of any ideas you all have .  Thanks, Paolo



Reply #1August 28, 2011, 07:25:04 pm

R.O.R-2.0

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #1 on: August 28, 2011, 07:25:04 pm »
So I''ve got a vanagon with a 1.9 AAZ.  A while a go the turbo went out and I simply removed it, plugged up the turbo oil lines and re routed exhaust and air filter(k&n in drivers side D pillar)  What can be done about the noise!  No tach but with stock diesel tranny in 4th It's bearable untill about 40mph and then a very unpleasant droning/bone rattling vibration increases until about 55 when it's still loud but smooths out a bit. It's definately rpm dependant and will do it in any gear at the same rpm range. I know putting the turbo back in will soak up some of the noise, but i'm satisfied with the power of the NA and like its simplicity.  Things I've done to try and quite things down a bit include. extra carpets over engine compartment (below cushion) , removed wall panels and installed butyl rubber on sheetmetal  and fiberglass insulation...  I havn't tried but have thought about wrapping the exhaust in some kind of heat proof tape,  different motor mounts, different muffler, different manifolds. Possibly some kind of clear plastic partition right in back of rear bench.  I need to quite her down, its driving me mad and is the only complaint I have with her. Let me know of any ideas you all have .  Thanks, Paolo

how worn are your motor mounts? im kinda almost thinking thats where most of your noise is coming from. how good is your exhaust system hung? are all the hangers rubber isolators? its not touching anywhere is it? no shiny spots on the pipe? do you have an air box and panel K&N filter, or a intake duct with a open element K&N pod filter with no box?

these diesels, as n/a, make ALOT of intake noise if they dont have a proper air box fitted. im kinda thinking you have just an open pod filter. and i bet thats where most of your noise is coming from..

why not just re-fit a turbo to it like theres supposed to be? do you have any idea how much the turbo quiets things down? its the best muffler you can have, it quiets things down substantially, and makes more power.. its a win-win situation..

it doesnt just quiet down the exhaust either, it also quiets the intake quite a bit also. well, you figured out that it makes things A BUNCH louder with it not installed..

i would say to fit some new motor mounts if they are old or worn, and either fit a good air box and muffler to it, or else put your turbo back on.. i would just put another turbo back on it, personally.. if nothing else, just for the increased torque, and mileage gains..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #2August 28, 2011, 07:43:10 pm

the caveman

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #2 on: August 28, 2011, 07:43:10 pm »
I did so much to quiet mine down, with limited success. The biggest difference was attaching the snorkel to the intake once i got the intake sorted. It was quietest when it was full of luggage on big trips. I was going to build a box to cover my VO tank that was where the third seat would have been, I'm sure that would of helped. The other thing you can try is some dense foam, maybe 4-6 inches thick over the back section
" I'm a vegetarian,not because i love animals, it's because i hate plants"
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Reply #3August 29, 2011, 04:41:57 pm

paolomarks

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #3 on: August 29, 2011, 04:41:57 pm »
Thanks for the replies.
I guess I have 2 questions, firstly, how does the turbo quite down the intake. (mine is an open element by the way) and secondly where can I find a good used kkk turbo. My turbine shaft broke right in the middle and the exhaust turbine was spit out and lodged itself in the exhaust pipe.  My core is good and all I really need is a new shaft and probably a new exhaust turbine.  Thanks, Paolo

Reply #4August 29, 2011, 05:44:29 pm

Mark(The Miser)UK

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Mark-The-Miser-UK

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Reply #5August 29, 2011, 05:58:45 pm

R.O.R-2.0

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #5 on: August 29, 2011, 05:58:45 pm »
Thanks for the replies.
I guess I have 2 questions, firstly, how does the turbo quite down the intake. (mine is an open element by the way) and secondly where can I find a good used kkk turbo. My turbine shaft broke right in the middle and the exhaust turbine was spit out and lodged itself in the exhaust pipe.  My core is good and all I really need is a new shaft and probably a new exhaust turbine.  Thanks, Paolo


well, it just quiets it down.. the same as how it quiets down the exhaust.. at idle, your intake will be quieter on a turbo diesel, than on a n/a. thats assuming both engines are running similar air intakes with open filter elements..

and you can look around in the classifieds for a used turbo..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #6August 31, 2011, 05:18:30 pm

madmedix

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #6 on: August 31, 2011, 05:18:30 pm »
Thanks for that link Mark; although the links inside it are broken and pop you over to a Romainian ISP :P
On my Jetta when I had her apart the first time I put dynamat panels over where the mounts would be for the rubber pieces attached to the muffler; and on the inside of the cab from the front of the console up underneath the firewall to absorb vibrations...not a huge difference, but enough...

Andy
'90 TD Jetta

Reply #7August 31, 2011, 07:06:05 pm

Mark(The Miser)UK

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #7 on: August 31, 2011, 07:06:05 pm »
Oh, I found if you click on the prev, or next buttons at least, they seemed to work 5 mins ago.
I'm sure there was another site for a diesel bus, but I can't find it in my saved links.
Turbo quietens inlet and outlet because it chops up the pulses from the exhaust, and even the thonking of the inlet. Drawback is some turbos whistle badly.
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #8August 31, 2011, 08:56:41 pm

R.O.R-2.0

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Re: sound proofing a vanagon diesel 1.9 na
« Reply #8 on: August 31, 2011, 08:56:41 pm »
Oh, I found if you click on the prev, or next buttons at least, they seemed to work 5 mins ago.
I'm sure there was another site for a diesel bus, but I can't find it in my saved links.
Turbo quietens inlet and outlet because it chops up the pulses from the exhaust, and even the thonking of the inlet. Drawback is some turbos whistle badly.


i would rather listen to the whistle of a turbo, rather that the ROAR from the N/A intake..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.