Generator Vibration

[Fred Mc]

My generator (Onan 6500) causes too much vibration and I want to isolate it better to cut down the vibration.

What have others done in this department.

Thanks

Fred Mc.

[TomCat]

Fred,

I got lucky, and my 5500 LP Marquis can hardly be felt at all. But I hear that small air bags under each corner are the best way to isolate your genny. Unfortunately, I don't know where there are found.
Hopefully someone will chime in with a supplier.

Jay
87 SaftLiner

[TomC]

Onan has really good motor mounts.  Should check to see if the gen rocks easily and no part of the gen or muffler system is touching the bus.  I've had three Onan gas gen and vibration wasn't ever a problem.  With a gasoline generator, you should have minimum vibration.  With a Diesel it will be more pronounced where the solution could be using the air bags under the unit-but then you need about 6" in each direction for movement.  Good Luck, TomC

[ChuckMC8]

Fred, check to make sure that one cylinder isn't misfiring due to a defective plug or wire, etc.

HTH chuck

[Tom Y]

Fred, I have a Onan diesel gen and I put air bags on it. Only 3 an almost 200.00. What a difference, the onan mounts were junk and a v setup at the gen end. So it setteled into the the rubber over time. I found the Wirco mounts but not sure if I still have the numbers. Wrico was pricey, so I found a supplier for them.  If I can help let me know. Tom Y

[FloridaCliff]

Fred,

I bought some from Grainger.

Work great!  You need to know thw total weight to figure what you need.

Heres a link to there catalog page:

http://www.grainger.com/Grainger/wwg/productIndex.shtml?originalValue=vibration+mount&operator=prodIndexRefinementSearch&L1=Isolators%2C

Cliff

[Dallas]

Just a thought out of my conoluted thinking processes....

Why not use 3 or 4 replacement tires and wheels for a hand dolly. Lay them down flat and bolt them to the base of the generator through the axle hole. Lay a rubber mat under them to keep wear down.

Air pressure could be regulated with 4, 1/8" lines to a valve connected to the aux air tank.

Tires and wheels are 4.10/3.50X4" and cost around $6 -$10 each.

Dallas

[Chris 85 RTS]

Check out the pictures of my setup.   Allows isolation in all directions and allows me to roll the unit out for service and was cheap cheap cheap.

http://www.flickr.com/photos/79505093@N00/sets/72157600857348856/

[Fred Mc]

Chris, I like your setup. also the price.

How do you prevent the dolly form moving on its own?

Thanks

Fred Mc.

[Ncbob]

Fred, m'friend...Onan made 6500 watt gensets for many years. I know I can lead you to the answer for your problem but will need the Model Number of the generator.  If it's a 6.5NH you'll be able to touch both sides ot the exhaust manifold pipe while it's running. If one side of the pipe is cool my guess is that you have either a plug not firing or a valve not closing properly due to carbon build-up.

If it's an Emerald 6500 (6.5NHE)...you won't be able to get to the exhaust because of the shroud.  If that's the case best replace both spark plugs...should be available from NAPA...gap them at .025.

After over 20 years in the Onan generator business I cannot stress enough that Generators need to be run under load periodically to keep both the engine and the generator end in good condition.

Dampness affects the generator end as well as the engine and exhaust system and will cause either to fail prematurely if not dried out regularly.  When you run your generator apply as much load as practical in order for heat to build in the rotating end ...ridding it of moisture.

You wouldn't let your main engine sit for 6 months without running it. Do the same with the generator and we'll read less and less about generator problems on all these boards.

Offered with the best intentions for all those poor forgotten generators. ;

NCbob

[Chris 85 RTS]

Fred Mc,

The pic on the bottom row first column in named Wheel Clamp.  I basically took the C channel and welded it in to two "L" shapes that form a rectangle.  The bottom "L" is bolted to the bus up against the forward firewall.  The other "L" is henged at the firewall, comes down and covers the wheels, and clamps in the front with two threaded rods.  When I want to roll the genset out, I remove the threaded rods, flip up the upper "L", attach extension rails, and roll it out by hand.

[Fred Mc]

In reply to NCbob, the generator is a 6.3 RV-LP Onan.

I just checked the exhaust temps and they are relatively even so it is firing on both cylinders.

Thanks

Fred Mc.

[grantgoold]

I took my 18kw duetz diesel generator and placed it in the driver's rear bay. I used a product (suggested by capitol rubber in Sacramento) that they had used specifically for damping vibration (it is a solid red rubber). It has worked wonderful for about 1 year and I see no evidence of deterioration. The generator weighs about 650lbs. I was truly impressed and glad I asked for some help from the "rubber guys"

Grant