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Virtually every other thread has some mention of soundproofing. Today I saw a 6BT sump with what looked like polyurethane around the sump this was a factory part and the cummins tec put the No in quickserve for me to find out if the sound proofing was seperate or if the sump and soundproofing were one, sure enough the sump and sound proofing are one & the same. Does anyone know how much difference it makes? has someone heard both and can give me a 1st hand account? would it only be an advantage for a stationary engine? These must therefore be available for 4bt's. I suppose I could put something around the sump to quiten it, but is it worth the bother?

Gaza
 

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Virtually every other thread has some mention of soundproofing. Today I saw a 6BT sump with what looked like polyurethane around the sump this was a factory part and the cummins tec put the No in quickserve for me to find out if the sound proofing was seperate or if the sump and soundproofing were one, sure enough the sump and sound proofing are one & the same. Does anyone know how much difference it makes? has someone heard both and can give me a 1st hand account? would it only be an advantage for a stationary engine? These must therefore be available for 4bt's. I suppose I could put something around the sump to quiten it, but is it worth the bother?

Gaza
On the Cummins website I was looking at what they had listed for the 4bt and I noticed there was a 5dB noise resuction package available. Nobody knew what it consisted of, maybe that is the answer!

EDIT: Copied and pasted from the Cummins website, bottom of the list...
Options.

Additional Information--------------------------RatingsPerformanceStandard FeaturesOptionsMaintenanceBase WarrantyExtended CoverageAdvisor

Cummins B Series engines are the ultimate in design flexibility. They give you hundreds of application options to meet your specific agricultural needs in every terrain under every condition. These options include:

Flywheels
Flywheel housings
Starters
Alternators
Oil pans
Air-handling options
Cooling system options
Accessory drive mounting options
Fan drive options
Plus noise reduction packages that eliminate up to 4.5 dBA of acoustic output
 

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The sump noise insulation is becoming quite common in other automotive diesels. Toyota has it in their 100 series landcruisers.
The Isuzu 4B series engines have a rubber mounted sump to gain some of the same effect (stop it being an echo chamber). It has a thick rubber sump/block gasket with another between the sump and the bolts which hold it on.
I took mine off for clearance reasons (gained about 10mm).

You can probably get much of the improvement by using underseal type paint on the sump. I've done this but haven't got my engine back in yet.
 

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Discussion Starter · #6 ·
The sump noise insulation is becoming quite common in other automotive diesels. Toyota has it in their 100 series landcruisers.
The Isuzu 4B series engines have a rubber mounted sump to gain some of the same effect (stop it being an echo chamber). It has a thick rubber sump/block gasket with another between the sump and the bolts which hold it on.
I took mine off for clearance reasons (gained about 10mm).

You can probably get much of the improvement by using underseal type paint on the sump. I've done this but haven't got my engine back in yet.
My 6bt sump is exactly as you describe Dougal. I never thought of it as sound deadening though. I was just happy the sump gasket was reuseable (as confirmed by cummins).

Gaza
 

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Wondering how good it would do to rhinoline the outside of the oilpan and valvecovers? 1/4 outa knock a good bit of rattle down.
That doesn't sound like a bad idea. The pan acts as a membrane that reverberates with noise. Adding mass to it should dampen the noise.
 

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i've used "Peal and Seal", which looks like a poor-mans sound deadening material, but is actually a roof-product? or some such building material. 6" wide, by 50' costs me about $35... Two rolls was enough to sound proof my FJ60. Basically super supe sticky tar-material, with aluminum on one side... so, when my 4BT is running, I plan to cover the oil pan, and valve covers with this stuff. You can stick mupliple layers on... it's cheap, heavy, and can withstand some heat (not really sure how hot... but I know roofs can get to 200F or close).
 

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I wonder if one of the following sprays applied to the sump and valve covers would cut down the noise without being too unsightly? I talked to the guy from second skin about sound deadening the body and he said his stuff works not by adding weight to the sheet metal but by absorbing the sound and turning it into heat. He said as long as you let it cure 30 days (I think) you could even put linex or some other spray on liner over it.


http://www.secondskinaudio.com/thermal-acoustic-insulation/firewall.php

http://www.secondskinaudio.com/sound-deadener/spectrum.php

http://www.dynamat.com/products_automotive_dynaspray.html
 

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Do you have pics of how it goes on? Are you pretty happy with it so far? I am anxious to hear how well it works.
 

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I am using spectrum and firewall spray. I also grabbed the gun from them. My air compressor was too small to keep up so I had to stop and wait to build pressure and then spray again. If you have a bigger compressor you won't have my problem and it will go on pretty quick. I added about a cup of water to a gallon pail to thin it because I wanted a smoother finish rather than a splatter effect. I really liked how it turned out and thought I could get away with using it as an interior liner (ditched my carpet) but it's not going to hold up to traffic so I suggest a more durable product over the top (I'm actually going to try painting it with Rust bullet since I really like that stuff and am using it on other part of the project).

I applied two coats of sprectrum on the firewall and the underside of the trans tunnel. After it dried I then applied Firewall to my firewall and underside of the trans tunnel. The firewall product did not come out of the gun well at all and splatters went everywhere making a mess so I stopped and applied the rest with a brush. I applied two coats of that too. I then applied spectrum with the gun on the inside of the rig. Total I ended up using 1.5 gallons of sprectrum and almost a quart of Firewall.

Product, Firewall is on top.



First coat of spectrum before thinning.



First coat of spectrum inside before thinning



Firewall product. I thought I had a better pic but I cannot find it and you can at least see it in this pic.

 

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Two more pics

Firewall



Inside on the first coat. The gun won't suck all of it out of the bottle and I didn't want to waste any so I just dumped the rest on and smeared it around. This is still just the first coat so a finished look was going to be acheived with the second coat. I don't have any final pics but it dries to a really dark flat grey or a fadded flat black. It scuffs pretty easy so that's why I'll be putting a top coat on of something more durable.

 

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cool... I hope it works out well, I never had any luck with spray in but that combined with a stick might be killer.. My goal is to have my 55 super quiet if I can. A quiet FJ55 is sort of like an oxymoron :)

Anyway here is my post from that other sound proof link. If you all have the time check out this link, it is killer and goes into the mechanics of sound deadening. I emailed him aobut the JC Whitney and the air duct stuff but he hadn't tried it yet. But his coined answer is there is no real solid cheap alternative. He found some option for about $400 that is the best bang for the buck called RAAM something I think (it is the last page).

My plan is a peel and stick and a carpet and maybe something else too. All this in addition to good weather stripping which is super important too IMO.

Cheers,
Andre

I did some spray in bed liner in my cab that I thought would help but didn't too much. The big difference with bed liner is getting professional 1/4" stuff sprayed in, not cheapo DIY stuff like I did.. But I plan on sound proofing with matting
(check out this link, the best info out there:
http://www.sounddeadenershowdown.com/ )

Then I plan to put some carpeting over that. Also good weather stripping goes a long way. My last truck was a tin can and loud as all hell.. Could barely hear the cell phone.. This one will be nice and tight and quiet...
 

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That's a good site. I read his showdown when I was deciding on sound deadening material and that's what lead me to secondskinaudio. Agreed on the weatherstripping, it does make a difference especially on the wind noise. That's why today's new cars have two or three levels of weather stripping on the doors. If I were to combine spectrum with peel'n stick stuff I think I would have fanstasic deadening but since I don't want to run a carpet I think I'll try this out first. It is different than bedliner.
 
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