On Jun 19, 12:10 pm, lugnut > wrote:
> On Mon, 18 Jun 2007 22:14:49 -0700,
> wrote:
>
>
>
> >On Jun 18, 8:48 pm, Hal > wrote:
> >> > The hole seems to have no treads in it. Factory smooth. It appears to
> >> > be some sort of a seal or something. I'm not sure if I can remove
> >> > that. For sure it reminds me of what car makers used to do to make
> >> > things tamper proof. If it is a tamper proof cap, how do I remove it?
> >> > In the old days we used to drill a 1/8" hole in to it. The hole size
> >> > seems just right for the screw, but it seems sealed. I'm concerned if
> >> > I drill a hole in there and there is an screw, then what
>
> >> No need to drill anything. Most likely what you are looking at is a
> >> port that could have been drilled and used for another purpose on a
> >> different model engine than yours.
>
> >> > I did spray carb cleaner in the carb and things did not change.
> >> > However, when I was maintaining a slow stream of carb cleaner the
> >> > engine stopped its hunting and ran smooth. This somehow tells me I'm
> >> > not getting sufficient gas in there.
>
> >> Sure sounds like a plugged up idle circuit. There should be either a
> >> removable idle jet or an idle mixture screw somewhere on the
> >> carburetor. If not you'll have to take the carburetor off the engine,
> >> remove the float bowl(f any) and use carb cleaner/compressed air to
> >> try and clear all the passages.
>
> >> What model engine do you have? Model/Type/ser from the fanshroud would
> >> help.
>
> >> Chris
>
> >The tractor is 917.271832. Engine is B&S 461707 type number 0147-E1.
> >Carb is B&S 693479.
>
> >If I could find the idle mix screw, I can make the correct adj. The
> >issue is that there are no adj screws other then one
> >for RPM. No mixture adj. All the diagrams, including the Sears one
> >show a key no. 147, part number 693508 Jet-Pilot.
>
> >However on the carb itself there is no such part. I'm completely
> >amazed. Even a Haynes small engine manual shows where a 4 screw gas
> >pump carb (exactly like mine) would have the mix adj. All the info on
> >the web, the Sears manual and the repair manual show a little screw
> >for idle mix adj. The carb rebuild kit part number 693503 includes
> >this small screw as well!!!!
>
> >Thank you,
> >Fred
>
> My 1998 vintage B&S 16HP Vtwin has no idle mix adjustment -
> only idle speed adjust. It is very sensitive to debris and
> moisture. I have had some problems with moisture
> condensation in the fuel tank that eventually gets to the
> carb. It seems to help to occasionally drain both the tank
> and the carb bowl. Mine has a drain screw for this. Also,
> I turn off the fuel and drain the carb if the mower will be
> idle for a few weeks. You can likely reused the bowl gasket
> and clean the passages pretty well with a can of Gumout or
> B12. Remove the screw plugs from the passages to make sure
> you are getting the solvent thru them.
>
> Lugnut

Folks,

I thank all of you who shared you wisdom and knowledge with me.

Here is the latest update:

I wanted to order a rebuilt kit first before committing to a new carb
for $152 from Sears. I first looked at Sears for the carb kit. They
wanted around $28 plus $7 for s&h. I looked for the B&S p/n on the web
and someone on Ebay had a kit with that exact number for about $22
plus free s&h. I ordered that and got it 3 days later.

I replaced the 6 pieces of the pump first since they were easy to do
right on the mower. There is a spring, a cap, two gaskets and two
diaphragms. The rubber looking diaphragms on mine looked real aged and
starched. I put it all together and started the mower. No change. It
still surged at idle

Next in the kit there was top washer which sits between the carb and
the air filter housing. I replaced that, No change

Next there is 1" bolt which has a very small screw with a hole in it.
This is called the main jet. Replaced that. No change

Only parts left were two washers for the idle speed shaft, and a small
screw with precision machined holes. This part required me to take the
carb off and apart to get too. However having the part in my hand
allowed me to locate in on the inside of the carb looking down at it.
So, I took a wire tie and clean the one already on the carb. Started
the engine. Things seemed a bit better, but not really fixed. Still
misfires at idle and sometimes at full load

Next I took the carb cleaner and placed a small red tube thing that
came with it on it and spared right into the little hole. That caused
a tiny amount of while looking grass or fiber to blow out of the big
nozzle in the carb. After that the cleaner starting to come out of the
nozzle right on top of the throttle plate.

Started the engine and for about 5 min all ran well Very smooth
idle. At high speed things look ok as well. Just when there is no load
(the blades are not running) there is slight misfire once every min or
two. I think this has been there since day one. But idle is back to
smooth. I only ran it for about 5 min and left it alone.

I think its fixed.

Takecare,
Fred.