question on making generator more quiet

[encantotom]

hi all,

i have the 12.5kw yanmar genny. it is about as loud as i would expect. the genny compartment is nicely insulated as is the outside area.

i did notice on a picture of a genny compartment of someone elses a while ago that they had airbags on the generator engine mount. mine does not.

the noise level is higher than i would like inside the coach. i will soon take my sound pressure meter and measure the sound in side the coach to let you know how loud and maybe we can all compare noise levels.

have any of you done anything successfully to reduce the noise level inside the coach from the generator?

thanks

tom

[encantotom]

hi all,

well, after hearing michaels generator when he was here visiting, i decided to go further down my qwest to figure out how to silence it some more. his actual diesel engine is about the same noise level as mine. i have put more muffler hangers on the exhaust pipe for the generator with no help.

so, i took the one hp motor off the blower fan and had it checked out at a motor shop. it is just fine. there is clearly more noise coming from the blower fan than michaels.

so i took the blower fan out. it is made by dayton which is owned by grainger and i happen to have an account with them.

i took it apart piece by piece. mine uses bronze sleeve bearings and they clearly were worn. i only have 1700 hours on the generator.

the blower unit minus the motor is a 2C975 and is not made any more. however, parts are available for it. so, new bronze sleeve bearings and a new shaft were gonna run me fifty bucks. however, i really wanted ball bearings to quiet it up. ball bearings that fit in the mounts were going to be more like eighty bucks.

so i opted to buy a whole new blower with ball bearings for 170. there is a steel bracket welded to the old one to mount it and a piece welded to support the motor i will have to put on the new one, but this way i am sure it will be quiet.

next i will trace down the entire exhaust system and see what is rattling there.

the new blower comes on monday so i should be in business next week if i can get it welded quickly. maybe it will be an excuse to go buy a mig welder.

tom

[Richard and Rhonda]

Tom,

Have you or any of the other guys found a source for the air mounts for the generator. Most of the Prevosts I've seen have them, and also the most recent Newells. I must not be looking in right place on the internet.

[fulltiming]

Richard, try these sites:

http://www.vibrasystems.com/?EC=Product&ProductID=10
http://www.enidine.com/pdffiles/Airspring.pdf

[encantotom]

now that richard has my interest up in the motor mounts again, i may have to look at them.

on one hand, i dont really want anything that is hooked up permanently to the air system, so it would have to be air bad mounts that you fill up and check once in awhile.

or, maybe i will just check and see if the mounts need replacing with regular rubber isolation mounts. i have a source for them if they are a standard size.

i wonder what the air mounts would do for vibration isolation.

my blower is being delivered on monday, so i will have it in next week. i have to go get some more insulation to redo the compartment before i put it back in.

does any of yours have insulation on the bottom of the compartment where the blower is?

later

tom

[fulltiming]

There is no insulation on the bottom of my generator blower compartment.

If there is adequate room, extra insulation on the ceiling of the compartment would probably make the most difference. Increased attention to isolating the blower mountings might also help since it is right under the passenger's seat.

I don't think I would want air mounts on the generator tied into the coaches air system either. I would rather manually air them up. Tying them together to make it easier to pressurize wouldn't be a bad idea if they need attention very often.

[encantotom]

i have plenty of room on the ceiling of the blower compartment.

i will put an extra thickness on the ceiling.

the way the blower is mounted is there is a 1/4" steel plate welded that is about 3 inches wide on the top, and two sides. it is mounted with 6 screws on top of the insulation. not sure what else to do to mount it to isolate the vibration than what they did. to hold the blower cage up, there is a carpeted block of wood that slides underneath it.

tom

[tuga]

How do you guys make room in the generator compartment to work? I can get to my air filter to change the element, but I don't think there is enough room to do much else.

How can I get the generator to slide out a little further? I would like to lubricate the cable that releases the latch that holds the generator slide when the coach is underway.

[fulltiming]

Our generator blowers are not in the generator compartment itself but in the side compartment next to the generator. Trying to access the latch cable is not easy. We just have the 'little' 12.5kw gensets. You probably have the 20kw genset which is larger and leaves less room to get around.

I don't know of any way to get the generator slide to come out further without removing the bolts from the air pistons and providing some type of support for the generator as it is pulled out further but I will take a look later today.

[encantotom]

michael is right. ours is pretty easy to work on and there is plenty of room there to do stuff.

my blower is much easier to work on than michaels. since i dont have basement air's, i have more room underneath. my 110v air compressor is the only thing in the vented/slotted bay in front of the drivers side front tire. likewise, my generator blower is the only thing in the same bay on the passenger side. on those with basement airs, the passenger side has both the blower and the air compressor. so, mine is much easier to do things in those bays. i posted a picture of my air compressor compartment when i redid it last spring.

as for the latch and cable, i replaced my cable after it totally stopped working. it is not for the faint of heart.

it is a choke cable that only costs a little, but mine was stuck closed. you have to air up the front of the coach all the way, then climb clear underneath (support the front with jackstands, or a couple of twenty ton bottle jacks) and on the back of the generator compartment there is a panel that covers it all. it has bolts on it that you have to take off and the entire rear panel (about 2ft square or so) comes off. this panel has a notch in it to allow the exhaust to go through the panel.

then you have access to the latch. i took mine off, took it apart and cleaned and lubed it, then replaced the cable. it took me quite a few adjustments to get it to close and latch properly. there is not much space under there and i used a creeper to make it easy to get under there so far.

of course, it took me way longer than i am sure it should have, but everything i do seems to be the first time and it takes me a long time.

the cable itself would be very hard to lube. it is a normal choke cable, but since the end is bent and hooked around the latch, you cant pull the cable out to lube it. there is not a great place to squirt or force lube into it. if you take the cable off, it might be easier, but then a pain to put back on and adjust.

then again, you might figure out a way to lube it from the knob side of the cable, but i sure couldnt get enough lube to go down to make a different.

if it isnt terrible, i wouldnt do anything other than try to get a penetrating oil down the knob side. or plan on installing a new cable. i did get the cable from newell only because it was easy, but it is a standard choke cable.

the one i took off had a T handle, the one i put on was just a knob.

later

tom

[HoosierDaddy]

My '93 has a T handle cable. If you rotate the T it will lock the cable in place. I think it's the same cable they use to set engine speed. I've seen them on tow trucks and fire engines. I squirt a light oil in at the handle end to lubricate. To lube the latch I used WD-40 with an extension tube and reached in as far as I could and sprayed it. I realize that is not an elegant solution but I DONT want to have to crawl under there to fix a broken latch!

[HoosierDaddy]

When I reworked the gen compartment on my '78 I got a sound deadener material that is foam with a layer of lead sandwiched in the middle. I think I used 3/4". It's very effective. I got it from Martin Diesel: http://martindiesel.com/ They are located about 50 miles from where I live. Good people.
Both of my Newells use the air bags for gen mounts. I reworked the ones on my '78 by adding air lines that run to the front and terminating with schrader valves. I think my '93 has an air pressure regulator in the gen compartment that is plumbed into the coach air.

[tuga]

My '93 has a T handle cable. If you rotate the T it will lock the cable in place. I think it's the same cable they use to set engine speed. I've seen them on tow trucks and fire engines. I squirt a light oil in at the handle end to lubricate. To lube the latch I used WD-40 with an extension tube and reached in as far as I could and sprayed it. I realize that is not an elegant solution but I DONT want to have to crawl under there to fix a broken latch!


I lubricated my 93 the exact same way. Spraying WD-40 on the cable actually allowed the fluid to seep into the cable. It took several sprayings, but it worked.

I don't have that much room with this 20KW genset. Now that it is 10 years old, guess I'll have to figure something else out.

Glad to hear about the back panel that can be removed to access the latch.

[Richard and Rhonda]

Tuga,

On mine, the air cylinder rod is pinned to the front of the slide. Two circlips hold the pin in place. I remove a circlip and drove the pin out. The gennie will come out a couple more feet before the rear rail starts to clear the rear most support roller. It's still a tight place, but that gives a little more room.

[encantotom]

i tried lubing mine that way, but just didnt work.

the airbags are interesting.

the T handle cable, i couldnt find anywhere and newell didnt have them anymore.

as for the insulation, i use the stuff from www.bondedlogic.com

it is available locally and from jcwhitney. i use two layers and it works great.

fairly inexpensive.

tom

[Neweller]

Tom, I seen some different "T" handled style cables on ebay anywhere from $15-25 for various models of autos. Not sure exactly what end you have or length needed.

Also, I came across this company at a trade show called Barnes Distributing and they have some pretty good products. One product called Super Gel Lube penetrating grease with PTFE is great for this application and it last a lot longer than WD-40 or chain oil.

I set up a wholesale account with them and buy welding and auto body supplies from them at a nice discount. For those of you who may have interest.

Here’s a little description on the product.


• Penetrating grease fortified with PTFE and extreme pressure additives for maximum protection in severe applications

• Thin in consistency when first applied allowing it to penetrate tight fitting areas where other greases fail to reach

• Features a fast evaporating formula which causes the lubricant to quickly set up into a gel-like grease consistency

• Formulated with tackifiers for excellent adhesive cling properties allowing the lubricant to stay in place where it is needed; Resistant to slinging, throw-off and water wash-off

• Contains corrosion inhibitors for protection from the harsh environments

• Temperature range of -20° to 300°F

• Applications include lubrication of both ferrous and nonferrous metals on slides, chains, open gears, hinges, pins, cams, rollers and cables


The company has a lot of other great lubricating products as well.
For the company website click HERE (http://www.barnesdistribution.com/)



Ken

[encantotom]

making progress. i spent hours taking out the old deteriorating insulation and getting the adhesive off the walls and sanding the metal down.

i got the new blower and had the brackets welded on. i opted to put extra strengthening on the bracket that holds the electric motor to the blower.

now i will paint the welding areas and

am waiting for it to get above 65 degrees so i can re seal the metal walls and put the cement up for the 1/8" rubber sound isolation membrane after which i will put two layers of foil faced thermal insulation prior to remounting the blower and the air slide valve. (i have a leaking connector on the valve i need to replace when i find one).

i think it will quiet things down a ton.

then i can look for any exhaust noise next.

later

tom

[encantotom]

Well i finished the blower compartment.

i attached a picture or of it. in addition i made a new insulated pad for the panel on the back of the genny compartment that you remove from underneath. the other picture is of that. it is about an inch thick and i made it out of 3 layers of an insulated material i used everywhere else.

the edges are taped with duct insulation tape.

the blower is a ton quieter now with the new blower.

the genny still has a slight rattle, but it is what it is. cant do any more.

later

tom

[fulltiming]

As always, great looking installation.

[RAGster]

Tom,

I was getting a slight random rattle in my Yanmar/Kohler generator. I have determined the source to the the Facet fuel pump mounted before the Racor fuel filter that feeds the generator. I don't know if this is your problem, or if you even have one since I'm not familar with Newells, but I threw it out just in case.

Regards,

Glenn

[Richard and Rhonda]

Hey Ragster,

Welcome to our group. Many of us lurk on the BB site, because our rigs share similar hardware, and we share similar interests.

It's good to have participation from other perspectives.

Welcome.

[RAGster]

Richard,

Thanks for the welcome. The Newell and Wanderlodge coaches are works of art. For the afflicted, you can get great joy just from seeing the engineering design. While at times they test our patience and pocketbooks, it is hard to place a value on art.

Thanks,

Glenn