Genset question for Prevost owners

[Tenor]

I've been looking at the installations of gensets on the e-place and they look like the radiator is mounted in a bay without louvers in the door, but use a screen in the floor.  Do these pull air in through the screen, through the radiator and into a bay or is there a fan mounted behind the radiator blowing out and then forcing heat down through the floor?   I also have not been able to tell if the radiator is installed in the same bay as the genset.  How are these installed?  Thanks!

[edroelle]

I do not like the way they designed it on my Prevost but -

The radiator is in a remote location from the generator.  A fan, mounted high in the generator compartment, blows hot air down a duct, through the floor.  This air entered, through a screened hole in another area of the generator compartment.  This arrangement allows generator noise to escape without being muffled, and hot exhaust air can potentially mix with incoming air.  It is not very space efficient either.  You are welcome to take a look at it.

This spring or summer, take a look at Garth Miller's installation, at one of the rallies.  We designed his to be efficient and quiet, using inexpensive materials.  We can do the same with yours.

Ed Roelle
Flint, MI

[rip]

I put in an Onan so I did n ot have to deal with the remote fans and such. I cut two holes in the floor for intake and exhaust and that's it.I don't think I would buy an Onan again,but the install was simple with using a small space and it is quiet.I have a 10kw quiet diesel and I have had a lot of problems with the control panel.I think they finally got it fixed having 200 hrs. since the last fix
  Don

[Tenor]

Hey Ed,
I haven't forgotten or lost the pictures of Garth's bus!  That install works sweet.  I am just curious how this other system works.  I'm always looking to understand stuff!

[Skykingrob]

Hey Ed and Tenor
I am just getting ready to start on the gen install in my 91 Prevost. Care to share a link to the pics so I can see what you'all did? I would very much like to see what others have done as well.

Rob
91 LeMirage XL
Missouri

[Ray D]

1989 Prevost - I installed an 8KW in the engine compartment where the HVAC compressor was, it was a tight fit, not easy at all & I used the engine radiator for the cooling.  It works and I saved 1/2 a bay.  I will  take some pics if anyone is interested.

Ray D

[edroelle]

Rob,

I do not have pictures of my previous bus but here is a description.

I am no expert, but my 12.5 diesel generator was noted for being very quiet.  Here are some things to do to reduce the noise.
Reduce the high and low frequencies.
 
Enclose the generator in a separate box.  I used particle board but should have used wolmanized plywood.  I also put the box on soft foam rubber.
 
Mount the engine/generator on rubber mounts.  I used pneumatic rubber tires which also serves to roll it out of the compartment.
 
Line the box with solid, heavy material or lead. I used 1/8" solid rubber-like material
 
Install soft noise reducing rubber on inside of box.  I used fiberglass ceiling tiles.
 
Since you need a lot of air flow through the radiator, and a little through engine/generator, put the radiator in a separate location.  I did do this with about 85% of the air flow through radiator and 15% through engine.   My intake comes through the old A/C grille and goes to the left front bay where the radiator, squirrel-cage fan, and engine/generator is mounted.  The squirrel-cage fan blows hot air down below the coach
 
Sound goes in straight lines.  Baffle air flow or duct the flow and use soft material on the walls.  I did do this.
 
Install a quiet exhaust.  For me, this was trial and error and was not efficient and there is still room for improvement.  I tried about 6 combinations of designs and mufflers.  I ended with heavy wall pipe to a resonator, then to the first Chevette diesel muffler.  I then ran 20 feet of exhaust pipe and stainless flex pipe to the rear of the bus to the 2nd Chevette diesel muffler, and then out the rear.  The sound out the exhaust is verrrrrrrrry quiet.  I still have a small 'thunking' resonance in the first muffler.

[JackConrad]

Ed has given some very good advice. Another that we found helps is to separate the noise sources. we moved our radiator and fan to the rear of the OEM spare tie compartment and the exhaust exit just in front of the drivers side dive axle. This way, wherever you are standing you are only hearing the noise from one of the noise sources.  Jack

[steamguy56]

Ray D
1/2 bay space saved sounds real interesting, would love to see picks of that install.
  Danny

[Hodag]

Hi, Tenor.  In answer to your original question, yes you have it right.  In my "factory" converted Prevost the 15kw gen is mounted on a slide in the second bay, accessed through the passenger side.  Intake air is drawn into the bay from a cutout in the floor, along the curb side.  Through a big plastic cowl, the air is drawn from this slot through the radiator, which is mounted on the front of the gen and has its original cooling fan mounted on the front of the engine.  The hot air is then free to circulate around the engine and is ultimately exhausted through a slot in the floor on the other side of the bay, by way of a large squirrel cage fan.  With lead and foam shielding, this is a relatively quiet setup.  One advantage of the squirrel cage is to alleviate my paranoia that exhaust might leak from the coupling that allows the generator to slide out for service.  The downsides of this setup is that there is noise on both sides of the bus and that it takes up a huge amount of space -- nearly the entire width of the bus.  On the street side in this bay I have room only for a series of shallow shelves and drawers.  Hope this helps.

Bryan