12V engine noise reduction efforts...

[Power Wagon]

Has anyone tried reducing engine noise on a 12V engine?



I know, I'm strange, but I'm trying to be a good neighbor, and wondering what, if anything, people have done to reduce engine noise (not exhaust noise, engine clatter) emissions outside the truck.



I've found some sound absorbing stuff that could be painted / adhered to the block after a good steam cleaning, but it's not going to handle the area around the exhaust, and I'm not exactly sure where the noise is emitted anyway.



I've seen some engine blankets out there. Do they have any effect? What about the lower block / oilpan area? Seems to be kinda noisy under the truck... does noise come from there? That would be easy to help.

 

[LSMITH]

PW, lay on your back under a running engine (you might want to try it on a 4x4 ), the noise is incredible. I think a lot of the noise is coming for the pan area and lower block. The drivers side of the block on mine is also noisy with the pump noise added to the clatter and our injection pumps are quite similar. I realize that the valvetrain is different but there is not a lot of noise that comes from the valvecover area on mine. I think if a guy could get a good sound killer blanket on the pan and bottom half of the block he would have a pretty quiet engine from the outside of the truck. I have tried some of the paint/roll on sound absorbing materials in different applications and found that they were not worth the effort of installation let alone the cost. The engineered material fabrics (blankets) do work well however and are reasonably priced unless rated for use around the exhuast area. If it is going to be close to the exhuast area it will be quite expensive. Lots of industrial suppy companies have the materials and are typically way cheaper than specialty sources. Good luck.

 

[Boldt's Wagon]

PW: How noisy are the pumps by themselves when you ran the pumps on the test stand?

 

[Power Wagon]

In this thread:



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=16794



Is some interesting data about some aftermarket exhaust systems radiating noise from the pipes themselves, not necessarily from the outlet, that could be heard.



My truck sort of has a "drone" while on the road... where would I try to "deaden" it?

 

[Power Wagon]

Originally posted by Boldt's Wagon

PW: How noisy are the pumps by themselves when you ran the pumps on the test stand?

At idle speed, not loud. The noise on the test stand is MOSTLY from the injectors and the accumulators the injectors sit in, as well as the lines that run to them. The injectors sit in cast iron on the engine and I honestly do not hear them. But on the test stand, there's little to nothing to deaden the clatter they make while the pump's working. I don't really hear the pump making noise, either... though I suspect it does make some.

 

[Power Wagon]

Originally posted by LSMITH

PW, lay on your back under a running engine (you might want to try it on a 4x4 ), the noise is incredible. I think a lot of the noise is coming for the pan area and lower block. The drivers side of the block on mine is also noisy with the pump noise added to the clatter and our injection pumps are quite similar. I realize that the valvetrain is different but there is not a lot of noise that comes from the valvecover area on mine. I think if a guy could get a good sound killer blanket on the pan and bottom half of the block he would have a pretty quiet engine from the outside of the truck. I have tried some of the paint/roll on sound absorbing materials in different applications and found that they were not worth the effort of installation let alone the cost. The engineered material fabrics (blankets) do work well however and are reasonably priced unless rated for use around the exhuast area. If it is going to be close to the exhuast area it will be quite expensive. Lots of industrial suppy companies have the materials and are typically way cheaper than specialty sources. Good luck.

Howard... check out this place, and tell me what you think...



www.b-quiet.com



Thier stuff looks reasonable, but I have not asked them which / if any / how they can be used on a hot engine.

 

[illflem]

Although it's difficult to believe, removing the fan is good for at least a 20 dB noise reduction at idle. Only problem is getting used to the increased noise when it goes back on come summer.

 

[Power Wagon]

My fan kinda drums for a few moments when you start it, but then the clutch disengages and it gets pretty quiet... there's basically no "roar" from it at idle, and I don't even hear it at low speeds now that it's cold out.

 

[LSMITH]

PW, the stuff you put the link up for is not what I have had good results with. A little digging came up with products more like what I have used,



http://www.acousticalsolutions.com/Desc-composite.htm is like I was thinking about.



http://www.soundstop.com/exhaustwr.htm this company has pre-made engine covers and exhuast wraps, more than likely a small fortune but very nice.



http://www.lamatek.com/Acoustical/foamspec.htm this is some really nice stuff too.



A while back I bought some foil faced foam from WW Grainger that worked well and was really reasonably priced. I do not have access to the catalog or account anymore. The links I have put up will give you a better idea of what I am talking about, I have used these types of products and know they do work well. You must be a nice fella, I on the other hand would do the cab top to bottom and let the neighbors deal with it while riding in silence At some point I would like to do my cab, I find the noise of the Cummins to be a necessary evil and not desireable at all. Hope this helps.



On the exhuast drone, it seems that most have found that the noise comes from the long straight piece of pipe. By making the pipe either more rigid or more flexible the harmonics have been reduced. I think a piece of flex pipe in the middle of the straight section would do wonders.

 

[Joseph Donnelly]

TDR #13, p. 40

 

[Power Wagon]

Originally posted by LSMITH

A while back I bought some foil faced foam from WW Grainger that worked well and was really reasonably priced. I do not have access to the catalog or account anymore. The links I have put up will give you a better idea of what I am talking about, I have used these types of products and know they do work well. You must be a nice fella, I on the other hand would do the cab top to bottom and let the neighbors deal with it while riding in silence At some point I would like to do my cab, I find the noise of the Cummins to be a necessary evil and not desireable at all. Hope this helps.



On the exhaust drone, it seems that most have found that the noise comes from the long straight piece of pipe. By making the pipe either more rigid or more flexible the harmonics have been reduced. I think a piece of flex pipe in the middle of the straight section would do wonders.

The noise doesn't bother me at all. When I'm alone, and it's not too cold, I roll down the passenger side window to hear that wonderful 6 cylinder cackle. However, I take my oldest daughter to school at about 7:15 AM every day, and on weekends or holidays (like today) I drove my kids around thier paper routes. Going to have to do that for a while, too, because my son severely sprained his ankle on his route yesterday. I'm sure the recipients loved that diesel clatter outside thier house at 6:20 AM this morning... NOT!!! There's a couple spots where you gotta nail the throttle pretty good, as well, because it's very steep. Might end up investing in a muffler just over that...



Anyway, just trying to muffle a little of the loudest outside clatter. The exhaust isn't really all that loud at idle, so I'm not particularly concerned, but my truck sits and idles about 2-5 min every morning I have to drive her to school...



Anyway, on long trips, the droning could get tiring (though it's not bad, it might be much worse with the trailer on behind), so I'll see if clamping on some steel bar dulls it. Being a 2WD club cab, I now have basically about 6 or 7 feet of straight pipe under the cab and front of the bed. I'll get 4 clamps and 2 chunks of steel to clamp them on and see if works. I'll let everyone know if it does any good.



Do you suppose the orientation of the steel sections should matter? Like, mounting them on top would prevent up/down motion, no? Make no difference?

 

[Power Wagon]

Originally posted by Joseph Donnelly

TDR #13, p. 40

Cool.



I, uhhh... don't have that one. I think I have only the last 2, since I think the wife tossed all the previous ones out



Care to summarize?

 

[LSMITH]

Originally posted by Power Wagon







Do you suppose the orientation of the steel sections should matter? Like, mounting them on top would prevent up/down motion, no? Make no difference?

I have exactly ZERO idea, sorry. One thing that you might try is to get a resonator throwaway from a 24V and put it in the system. I have only a resonator in mine and get no drone at all. It will not reduce the noise much if any either.



I don't have the old TDR's either, can't help you.

 

[Lurch]

When you turn em off they're pretty quiet.



Lurch

 

[Power Wagon]

Originally posted by EKarr

When you turn em off they're pretty quiet.



Lurch

And yer auditioning for what standup comic show?

 

[Power Wagon]

Originally posted by LSMITH

PW, the stuff you put the link up for is not what I have had good results with. A little digging came up with products more like what I have used,



http://www.acousticalsolutions.com/Desc-composite.htm is like I was thinking about.



http://www.soundstop.com/exhaustwr.htm this company has pre-made engine covers and exhuast wraps, more than likely a small fortune but very nice.



http://www.lamatek.com/Acoustical/foamspec.htm this is some really nice stuff too.

Ok, so I spent quite a while and gawked all over those sites.



Some of them are really interesting.



Precisely which materials would you YOU use and how would you actually put them to use?

 

[LSMITH]

PW, of the stuff I found I like the WM2 whispermat from the first link. I would line the underside of the hood and cover the fenderwells to start. A complete as possible lining of the engine compartment should do wonders. I would also get a foil or mylar facing to help with moisture and heat, foil looks cool too. I would need to know what temp the oil pan and block can hit can hit before going after them. If less than 200* (and it should never get that high) then just about anything will be OK. I think a liner on the hood, fenderwells and pan/lower block would get the result you are looking for.



Water resistance is going to be an issue as the material will not perform if saturated, so a closed cell foam is needed. Other than that, the materials found are all comparable for noise reduction ability. I still think that good material can be had from Grainger or McMaster-Carr for less than what the links were showing. You should try to find a local friend in business that deals with these companies. As I said, I do not have the ability to buy from these companies anymore or I would do some digging.



I wish we were closer geographically, this is a project I would like to participate in firsthand. Let me know if I can help.

 

[Power Wagon]

I've tried to find someone, but nobody around here seems to do anything like that.



Perhaps if I find stuff that works and makes a demonstrable noise reduction, my former employer may get into doing it.

 

[LarryB]

Check this out!!

 

[LarryB]

And this!