[AT] spark plug thread repair and ford 3000 fuel pump pressure

[Ken Knierim]

On Wed, Apr 21, 2010 at 9:03 PM, Don Bowen <don.bowen at earthlink.net> wrote:

> I am about to head back to the Ozarks in a couple of months.  There are
> a couple of projects waiting me.
>
> One is my '65 Ford 3000.  The last time I ran the tractor it needed
> almost full choke to get any power.  I checked for fuel flow and cleaned
> two of its three filters.  I suspect either the tank filter is plugged
> or the fuel pump is bad.  I would like to take an electric fuel pump
> with me for testing so does anyone have a recommendation on the pump
> pressure?
>
> Second project is a friends chainsaw with a stripped spark plug thread.
> He could not tell me the name of the saw or the plug size.  What are the
> typical small engine spark plug thread sizes and depths?  I do have some
> from my days of repairing Corvairs but being in remote areas of the
> Ozarks it would seem that a selection of common sizes would be good to
> have on hand.
>
>
The chain saw spark plug will probably have a  standard 14 mm thread pitch.
You can get a thread restoring device from NAPA and others for under $15
that might do the trick (if it's long enough since many small engines have a
rather long threaded section). If you need to cut a new set of threads the
14 mm uses a 1.25 mm pitch. I got one recently from McMaster-Carr (
www.mcmaster.com) and I'm sure there are lots of others that have them. The
14 mm size is pretty standard though there are some smaller ones out there.
If you've got one of those, you'll probably have to get the plug and measure
it.

Not sure on the fuel pump. My neighbor got a forklift that didn't run and
found out that the fuel pump was part of the problem. It had a 6 PSI pump on
it and was pushing the fuel past the float, making it run too rich. He got a
2 PSI pump to replace it but could have used a $10 adjustable regulator with
the higher pressure one if he'd found that first.
Either way you'll probably want to make sure the pressure is just enough to
get fuel into the carb but not much more; taking the line off and running it
into a bucket should give you an idea of fuel flow.
Isn't the 3000 a gravity feed fuel system? On my Case tractors I found that
I could have the fuel lines all cleaned out but if I didn't have much for
fuel in the tank I could have trouble keeping fuel flowing (I don't run them
often so I keep the tanks low). Turns out the fuel line had a slight uphill
turn in it and a touch of air would cause the fuel to stop flowing. I think
it was breaking the siphon action; the carb was lower than the bottom of the
fuel tank but the fuel line routed slightly up for a distance before the
carb. Adding another couple inches of fuel to the tank solved that problem.

Hope this helps.

Ken in AZ