[Richard]

I traveled over to Bestgenman's shop this week to gain some professional assistance with replacing the hard rubber mounts on my genset with airbags. I did not like the low frequency vibration that came through the flow and the bed while the genset was running.

Gordon (Bestgenman) was a fantastic host and has quite a facility for fabricating about anything you could ever conceive. I did get a few elementary lessons on using a mill, hydraulic shears, and other proper ways of metal fabrication. It was a far cry from a hand drill, hacksaw, and hammer that I normally use.

Anyhoo, the install greatly reduced the vibration. While we were at it, Gordon showed me many ways to reduce the noise coming from the genset. I'll have to say that what I learned from a professional is that the noise reduction is not one thing. In addition to noise abatement materials, you have to find and seal every opening to the gen box. It was a pretty amazing demo to hear how much noise escapes from a 1/8 gap around the top of the gen door.

I won't list a step by step or list part numbers because honestly the process involves fabricating custom motor mounts to keep the ride height of the gen the same as it would be with the stock rubber mounts. It is not a project for the squeamish.

As we were reinstalling the gen into the coach, I ran into an issue that is funny now, but not so much at the time. When I slid the gen all the way in for a test fit. It locked with the safety catch like it is supposed to. First I forgot about the catch, so I spent thirty minutes tugging on something that wouldn't budge. Then when I remembered the catch, it would not release. A slightly firmer pull resulted in pulling the cable loose from the catch. Oops! Well maybe I said something slightly different. Lucky for me the front door was off the genset, so Gordon suggested that the catch could be released using the old credit card in a door lock trick. After fabbing a 8 foot long chisel, the catch released.

Now, how to put it right? All of the wiring was in place by now, it is a chore to take it loose. So I pulled the gen out as far as I could using a pallet jack and the picture shows my scrawny butt in the compartment.     I went in backwards over and around the gennie. It was a tight squeeze. What I discovered in the compartment was a misalignment between the cable attachment and the lock that had existed since day one. It was a matter of time before it jammed. So after a couple of misfires that was connected and all was well.

[lbrachfe]

How in the world did you get in and out of there ??? I guess "The Rubber Man Can" ...lol

[folivier]

Richard other than the airbags what else did you do to reduce the sound level?
I assume the airbags helped the vibrations but not the sound level?
A few months ago I bought some insulation from Gordon which was really nice stuff at a great price. He also sent me some information on sealing the bottom opening where the ram slides. I haven't done that yet, maybe this winter.

[Richard]

Forest,

I removed (it was falling off) the insulation from the front door panel and installed some of Gordon's aluminum/foam/vinyl/foam material to the entire door. I sealed the edges of the foam with the aluminum foil tape. I placed an additional foam rubber seal on top of the existing seal around the entire perimeter of the door. I am in the process of fabricating a piece to seal the 2 by 2 channel where the cylinder is. An amazing amount of air and sound exits that hole.

Also he demonstrated to me how much sound the blower makes on the passenger side by temporarily placing some of the acoustic barrier material in front of the fan, but not closing off the louvers or course.

Correct, the air bags attenuated the vibration but do nothing for noise. The vibrations made it hard for me to sleep with the gennie running. My gear head brain would register the slight change in vibration normal with the gennie loading and unloading as something just went wrong. That would wake me up many times during the night.

[ccjohnson]

Richard, On our '92 there is a plate that can be taken out removing 4 bolts that gives you access to the back end of generator compartment. You still have to go in from underneath the coach though.

[Retro]

Very interesting Richard, I was thinking of changing the isolators for my gen, do you have par #s for those air bags?
I would be happy if I could dampen more vibration from my gen, I think the air bags would do the trick. Mine is stationary, it doesnt slide out and it has a rad up front that I plan on tying in with the rear engine for extra cooling so im not too worried about sealing up the gen box. Also adding a coolant pump to help circulate the engine coolant, probly operate it by a senser and a override switch.

[Richard]

I think I will let Gordon weigh in on the part number. It may be different for your genset. I'll look next time I am at the coach, but my feeble memory chip thinks something like Firestone 2M1A. The reference literature you are looking for is http://www.mrostop.com/pdfs/Firestone_ai...atalog.pdf

Also you will need to add some flex mechanism to the exhaust pipe so that when the engine/gen head floats it doesn't hard couple to the exhaust or you will loose some isolation and also bind the floating mechanism.

On piping the generator coolant to the engine. Why? How will you activate the fan on the BIG radiator.

When I made reference to sealing the hush box, it still has air in and out flow. I was sealing the openings around the door. A lot of noise was leaking out that door.

[bestgenman]

The air spring P/N is W01-358-7001. The flex is of the bellows style rather than the spiral style, I keep them in stock.

I recommend NOT tying your cooling systems together without a heat exchanger in between. There have been way to many main engines lost because a hose breaks on the genset and all of the coolant slips away. Not such a big deal if your main has a low coolant level sensor but still a pain!

The late 80's Newell's ran a circulating pump to help the genset coolant circulate through the hot water heater and sometimes an air exchanger inside the cabin.

[Retro]

I will have to measure them up and see what will fit, yes I realize the exhaust will have to be considered as well.
I dont see any reason why the coolant lines couldnt be tied together, a chance of a leaking hose to me isnt a good enough reason, that can happen on either end. Its the same coolant in both engines so i dont think a heat exchanger is nessesary either. I will valve the system and have a switch for the pump. The fan for the big rad is hydraulic and runs off the power steering pump.
On hot days I will have the extra cooling when its colder I will have the extra heat.

[Chester Stone]

Richard, I am interested in how you put a better seal on the generator front door. Any chance of posting a photo?