Zenith Carb on '69 Ford 2000-Float setting?

[Bob_Young]

Need to know the correct float setting for this carburetor....the measurement plus from where-to-where the measurement is taken. Would also like to know the suggested initial setting of the idle mixture screw.

Went to work on getting my sidelined 2000 running. Found that my Dad had replaced the Holley with a Zenith back in the late 90s sometime...and had no luck with it. The reason for that, I found, was that the Zenith float was a leaker and filled up with gasoline. Gasoline ran right through the thing and drained onto the ground when I first tried to run it.....Same thing he said the Holley was doing, as I recall.

Put in a new float and got it running, but it now seems to be very lean. Have to run with the choke half out to keep the RPM steady. Both my IT manuals address the Holley, no mention made of the Zenith. No other paperwork has been found.

BTW this is the 3 cylinder 2000. Soundguy, this is the same carb you linked me to in ytmag.com the other day....13913 is the number on the tag.
Bob

 

[Soundguy]

Try 1/4"

I've mainly messed with the MS carbs.. but do have a zenith on my 850.. and it may well be the same as your 3 cyls..

I use a 1/4 drill bit as a gauge... works great.. Also.. flaot setting is not as fatally specific as you might think... as long as you get it close enough that it lets gas in the bowl when empty, and does shut the needle off before gas overflows into the main chamber past the venturi.. then it should be fine..

Check for holes or that it doesn't hang up onthe sides.. etc..

Soundguy

 

[Bob_Young]

Thanks, Chris. I've got it home now, so can tear into it at any time. I'll try the quarter inch drill later this week.
Bob

 

[bjr]

Hey guys, maybe I can sneak in a carb question on the same thread. This on a 430 Case gas tractor W/148B engine I think. I don't remember exact model of carb. I think its a MS. The carb. was just rebuilt and intially ran great. Now only way it runs is with the choke on. Could the float needle be stuck closed? Or is this a symtom of plugged fuel line? What end of the tractor do they start on? It's the neighbor tractor and his mechanical aptitude is marginal. Carbs are not my specialty either. I usually have extra parts left over they look more like park fountains leaking and spraying gas. Maybe I'm exaggerating a little but just don't like small parts detaillly type projects, so I'm not getting to close to this tractor. bjr

 

[Soundguy]

Needs choke to run is a classif symptom of a vacume leak OR fuel obstruction.

So yes.. crub in the float needle, fuel line.. fuel strainer.. etc.

Or a air leak in the carb.. say around throttle shaft.. or a carb 'halves' gasket.

to decide which:

Get her outside, start her up and get her running.. choke on.. etc..get a plumbers propane torch.. don't light it up turn it on full blast.. and wave it al around the carb.. if the engine speed/sound changes.. you found your vacume leak.

Soundguy

 

[rgc53]

Mr Young,

I had a Ford 3000 with a zenith card.
I had a similar problem, a mechanic told me how
fix it! take the arm that holds the float and
bend it up a little bit ,what is happening is as
the fuel enters carb. the float rises too soon
and pushes the needle up into the seat closing the door
the engine is starving for fuel ,which is why you have
pull the choke , give it less air for the amount of fuel the
engine is getting! if you bend it too much the engine will
run rich and foul plugs , try a quarter inch to start.

 

[rgc53]

I assume your 2000 has the same engine as the 3000
a 158 c.i. , the Ford manuel says the idle should be 650 R.P.M.
make sure your timing is right it affects idling speed
timing is 18*b.t.c.

 

[Soundguy]

IE.. adjust his float to correct level..

Sounguy

Mr Young,

I had a Ford 3000 with a zenith card.
I had a similar problem, a mechanic told me how
fix it! take the arm that holds the float and
bend it up a little bit ,what is happening is as
the fuel enters carb. the float rises too soon
and pushes the needle up into the seat closing the door
the engine is starving for fuel ,which is why you have
pull the choke , give it less air for the amount of fuel the
engine is getting! if you bend it too much the engine will
run rich and foul plugs , try a quarter inch to start.

 

[Bob_Young]

Finally got the tractor off the trailer today and into the shop. Haven't had a chance to monkey with it yet this week....setting the float level will be the first priority. Maybe tomorrow.

Chris:
That propane torch idea for finding vac. leaks is a winner. Gotta keep that trick in mind. That could very well be the problem. There could be gum or crud in there as well, though I've poked and prodded where I could. It's been sitting since '99 or 2000. The main jet was totally clogged when I first got into it.

rgc:
Yep, it's the 158 c.i. 3-banger. Same engine they used in the 3000, according to the IT manual. With the choke all the way in (off), the engine runs but keeps surging between about 900RPM and 1400RPM. Apparently it starts to die and the governor opens the throttle to keep it running resulting in the surge to 1400RPM; then the governor backs off. So RPM constantly bounces up and down. This carb doesn't appear to have an accelerator pump, but I may have overlooked it. Running lean without an a-pump, I'd expect it to bog when the gov. opens the throttle.

Whatever's wrong, the thing starts right up....but then it was always good that way.

One really weird thing: The hourmeter in the tach now reads 1528 hours. Last time I ran it in the late '90s I definitely remember seeing over 2200 hours....got no clue on this one.

Thanks for the suggestions, guys.
Bob

 

[Soundguy]

Surging can sometimes mean lean mainjet..

That propane trick usually works, .. I've seen people do it with starter fluid.. but I usually don't reccomend that one due tot he increased fire hazard.

WD40 also works ok as the juice temporarilly seals the leaky gaskets.. etc.. however propane torch is the easiest with least mess.. etc.. and quite safe in open air as it takes a specific concentration of propane buildup in the atmosphere before it becomes explosive.. etc..

Soundguy

soundguy