Smarty wrote:

The Daring Dufas wrote:

On 7/23/2010 12:14 AM, Smarty wrote:
Nate Nagel wrote:

On 07/22/2010 05:02 PM, Smarty wrote:
chaniarts wrote:

Smarty wrote:
I personally installed a Generac natural gas stand-by
generator 5 years ago, after a freak October ice storm
knocked out electricity in this area for nearly 2 weeks.

..snip..

I am open to any ideas and suggestions, and much
appreciate your time in reading this, and possibly
replying. Thank you very much.

home depot has 1.5" diameter silicone water tubing. if it's
not too high a temp, that may do you. it'll be far cheaper
to just buy a few feet of it and cut off lengths a few
times/year as pm.

I spent most of today searching out, buying, and trying the
'loop of hose' method, only to learn that the bending radius
for hose of this large dimension creates a loop which just
will not fit in the generator cabinet and also will not clear
the very limited adjacent carburettor linkages, governor
calibration screw, and assorted other parts. The stronger
radiator hose with internal helical wire is sturdy but very
difficult to bend to a tight loop. I did not buy a piece of
silicone tube, but I did play with some and it is also quite
stiff due to the thick walls, preventing a small radius bend.

I have ordered a couple hump connectors and lined T-bolt
clamps, and also have 3 more Generac bellows here which came
from my parts supplier. I am going to experiment further to
see what remaining options I have, including coating the
bellows, installing the hump hose, or possibly relocating
things slightly. I am quite certain that there is no way to
significantly move the air cleaner assembly without serious
re-design of the internal cabinet brackets, sheet-metal, and
plastic housing, none of which I have any real desire to screw
around with. Using the current placement of everything, I am
down to either a strengthened bellows, a hump hose, or
replacing the standard bellows every 9 months or so in the
preventative maintenance cycle.

The failure of the 2 bellows are fairly similar, small holes
not much bigger than a pin hole, developing on the moving
engine / carburettor side of the connection (versus the air
filter stationary side).

I would guess that the peak-to-peak vibration of the bellows
creates maybe a 3/8" to 1/2" excursion in the worn area of the
rubber at the engine rotation frequency (3600 RPM as I
recall). The damn bellows has a wall thickness of no more
than about 1/16th of an inch of rubber, and is far from being
a "heavy duty" construction compared to the hoses and hump
parts I see with 4mm thickness or more.

I will update as I learn more. Thanks again!




If the carb is moving 1/2" is there a problem with the engine
mounts? Maybe even flywheel out of balance, or a misfire? That
sounds like an awful lot, a 4-cyl. or greater engine at 3600 RPM
should not be moving that much IME. Probably hard on the
coupling between engine and generator too.

nate

The generator has a one cylinder, 14 HP engine. The overall
excursions, as I 'guesstimated' in my prior comment, are maybe 3/8
to 1/2 inch peak to peak, which is basically oscillating about
3/16 to 1/4 inch in each direction. The vibration has been about
the same from original installation to the present time, so I
don't think that the motor mounts have worn appreciably. It is
possible that the mounts may have a problem from the factory
which I and the Generac technician who serviced the unit under
warranty may not have noticed.

The bellows have about a half an inch of expansion and contraction
space and would appear to be adequate to deal with the vibration
in terms of lateral 'play'. There are no specs or other
adjustments, calibrations, or measurements published for any of
this.

Perhaps the one cylinder engine explains why there is more
vibration taking place than you originally expected for a 4
cylinder design?

I confused, which model Generac standby unit has a one cylinder
engine and who manufacturers the engine. The reason I ask is that
I've never seen a Generac automatic standby gen-set with a single
cylinder engine built in the last 10 years. Back in the 1990's, I
installed a number of 8kw Generac automatic standby systems that
had the Vanguard V-twin Brigs&Stratton engine then in 1999 Generac
developed their own V-twin for the home and RV gen-set market. The
last Generac system I installed was several years ago and it had
the big honkin Generac V-twin. Somebody has even built a chopper
powered by one.

http://www.youtube.com/watch?v=C6hWtuVepDU

Of course, I reread your post and it doesn't say yours is an
automatic system or the kw rating. I've serviced single cylinder
automatic units but they weren't Generac.

TDD

Thanks Nate. My Generac is described at this link:

http://reviews.northerntool.com/0394...ort=rating&dir
=a sc

It is an extremely popular and highly rated unit. Home Depot and other
places sold (literally) hundreds (possibly thousands) of these in the
aftermath of the October ice storm which devastated the Northeast area
I live in a few years ago.

This one cylinder model, at 14.5 HP, makes 7KW of electricity, plenty
adequate for a smaller home.

You will see the reference to one cylinder in the link.


In case you have trouble with the prior link I stated above, here is a
shorter link to the same page:

http://tinyurl.com/268lhp3