Engine compartment soundproofing on a ZIL 131

[ChrisClemson]

Well.... noise reduction really.
While the noise of the engine inside the cab isn't as bad as it could be, I would like to make it quieter.
I stumbled upon this review from a yachting magazine:
http://www.nkgroup.co.uk/file/2014/06/M ... rticle.pdf

While it's talking about yacht engines, I'm sure the same principals apply to trucks.
I'm thinking that "thicker" generally equals "better" and having a lead layer is "better" (from a noise point of view) than non-lead.
I've seen some other companies that do general soundproofing for campers etc, but seem to be <20mm thick, and quite a lot seem to be just foam of some description.

Has anyone tried to quieten their ZIL?
What kind of stuff did you use?
Would this extra padding cause problems for engine cooling?

My neighbours and I would appreciate any guidance you can give

Cheers,

Chris

[aardvark64]

If all else fails, get one of these, e.g. from Russian Spares (http://russianspares.com):




Best wishes, Colin

[zoltan]

Bitumen flashing is quite agreeably cheap and easy to fit, that will be where I start when the noise of the glorious Gaz V8 becomes too overbearing. The Czech guy Morcak used old conveyor belting glued in his with carpet over the top. Nice and dense but not too expensive

[duncan]

You need two things: Weight to remove the panel vibrations (heavy drone noise), and soft padding against the high whine.

Get the heavy plates and glue them to all your engine covers. This will reduce the vibrations which cause your engine covers to work as big speakers. There are many types of weight-plates available, the important thing is to take one that is able to take some heat without giving off poisonous gasses. Some of the really cheap plates will give a horrible smell and produce Naftalin which is quite unhealthy. The better ones (made of Alubutyl) are still very affordable, I spend under 150 euro one covering my (very large) engine doghouse.

You can try with only the heavy damping plates, maybe it's enough already. If not, add some foam padding, thicker is better usually.

One more important thing to consider is moisture between the engine cover and your isolation, which will rust your panels through in no time, especially if you glue sponges to the metal.

[zoltan]

The Tatra must be the noisiest truck out there? Air cooled+ engine right next to the driver

[ChrisClemson]

If all else fails, get one of these, e.g. from Russian Spares (http://russianspares.com):




Best wishes, Colin

Hahaha! I'd only wear that if they came with night-vision goggles

[aardvark64]

They do (as modelled by one of my kids):



Hope you get the sound insulation sorted - I like the sound of the Zil V8 but never drove my old one more than 20 miles at a go (except when I delivered it to its new owner).

Best wishes, Colin

[Jorgus1983]

They are brilliant as modelled at wagtails at 1 am

[ChrisClemson]

They do (as modelled by one of my kids):

Hope you get the sound insulation sorted - I like the sound of the Zil V8 but never drove my old one more than 20 miles at a go (except when I delivered it to its new owner).

Best wishes, Colin

Thanks!
Mine doesn't sound as good as a V8 - it has a Cummins B engine in it instead.
However, it means I won't completely bankrupt myself when I go and have fun in it....

[stevedennis]

ear plugs - cheap, throwaway, easy to fit, quick and do the job in the Praga!

Doesn't rot out the engine covers either!

[jamie_grieve]

How silly would rolls of lead flashing be?
It wont melt, it's heavy, thin and easy to form and not hard to get into tight spots and at the price which although not cheap is not a lot compared to fancy soundproofing? You get it in different thicknesses, widths and lengths to suit all tastes.
Just a thought.

[ChrisClemson]

How silly would rolls of lead flashing be?
It wont melt, it's heavy, thin and easy to form and not hard to get into tight spots and at the price which although not cheap is not a lot compared to fancy soundproofing? You get it in different thicknesses, widths and lengths to suit all tastes.
Just a thought.

Hmm, yeah. Some of the more funky acoustic stuff seems to have a layer of lead, sandwiched between foam and thermal layers.

[ChrisClemson]

ear plugs - cheap, throwaway, easy to fit, quick and do the job in the Praga!

Doesn't rot out the engine covers either!

The plan was to be able to talk/listen to music at the same time.
Plus it would take ages to hand them out to all the neighbours before I start the thing.....

[Abrs]

You'll never be able to quieten one those engines down enough to listen to music on the radio & talk to your passengers!! At best you could hope to use an ipod etc instead

[Rob Reznik]

Well.... noise reduction really.

Its not noise its called music - you just have to change your thinking ;) and maybe move house!

[julian]

Yep, those blue things are over priced ear plugs that we purchased on the ferry, as we forgot the ear defenders : (

On the forward control 101, the bulk of the noise was/is airborne, as in comes through directly on the air, via various holes / flaps etc.

Before youve got the cab air tight (ish) then i think that the lead stuff is not so much use (i fitted both, but i still have holes, unsealed flaps, etc)

My plan is to rebuild the engine cover on mine (the 101) from scratch anyhow, as its too much bother to lift off to just check small things, and is impossible to seal any better than it currently is.


But, yes, in summary - airborne first, before buying any lead : )