Carburetor power jet size

Anyone know of a chart or information to determine correct power jet orifice size for a TSX400? It is a fixed jet carburetor. Thanks in advance for any direction.

with no carb make or # or what they are found on or even a picture i have no idea what you are referring to and neither will most other
people. i am also sure a parts man wont have ant idea either.

TSX400 is the carburetor number. Maybe I did not make that plain. Marvel Schebler is the brand. This one is on a MM BF with Hercules engine fixed jet no power adjust needle. May have been used on others I am not sure.

Assuming the original was lost or missing?

I looked around, couldn't find anything on the power jet size per application.

I found this listing that offered several sizes. They sound big though, probably for adjustable mains.

There are several suppliers and rebuilders online. You might make some calls, see if they have the info or an professional opinion based on engine size.

You may have to make a guess, start small and buy a set of jet drills, work it up .001" at a time until it will take responsive throttle without hesitation.

I did see the designation "A" indicates fixed jet.

Hope this helps, let us know the results!
MS Jets

Some people don't read well.

Thanks Steve I called the folk you had the link to yesterday. They have a part # for the power jet but no size. They are supposed to call me back today. The jet that is in the carb is about .055 I do not know if it is the original jet as the carb has been rebuilt at sometime. I do not know that it is wrong either. I get a lot of black smoke.

Can you give some more symptoms?

Black smoke at idle?

Under load?

Both?

Does it drip gas if the fuel is left on?

Does it matter if the air cleaner is disconnected? Choke fully opening?

Do you know the history on the carb? Did it ever work properly on the engine it is on now? Has anything been changed or modified, drilled, blocked?

High float level, partially sunk float, or leaking/trashy needle valve will cause black smoke. A way to test the working float level is to remove the bowl drain plug, screw in a barb fitting and loop an open ended piece of clear vinyl hose up beside the carb. That will show where the fuel level is running. Just a guess it should be about 3/4-7/8" below the bowl gasket.

How is the rest of the engine? Good spark at the plugs? Distributor shaft bushings tight, points properly set, timing advance working and set?

Good compression, valves adjusted?

Oil good, not contaminated with gas?

Thermostat in and working?

Man you are full of questions! Just kidding I appreciate the help. Smoke and rough running at speeds higher than idle. No gas dripping. No change when remove air cleaner tube. Choke is open. Not sure on history of carb 99 % sure someone rebuilt it prior to my dad purchasing. Tractor has been sitting a few years. Has not ran the best since I started to get it going. A few weeks ago I posted here if I had a carb problem or not. Had lots of input I think you pitched in too. Had a chance to get back to it Saturday checked spark, good spark at plug wires all 4 of them. Checked timing and firing order #1 at top dead center distributor and wiring correct. Distributor is moved as far as possible in what I think is advance direction it can go. Which makes me think maybe someone had distributor off when tractor was restored. Not sure on timing advance mechanism. Above my pay grade. No timing light not sure I would know how to use one if I had it. Point gap at .020. Checked fuel flow close to a pint in 2 minutes. Not sure if anything been modified but I do not believe it has, nothing stands out to me as rigged up. Tank was terrible when I started but have corrected that. Thought I might have something got through to carb so pulled it off and broke it down again. Did not see anything but have blowed it out good. Been wondering if jet could be too big from possible rebuild by PO, thought good time to check on it. When first started on this and got it started for first time had some blow by as smoke came from oil fill tube. Removed new spark plugs soaked cylinders with oil a few days all 4 cylinders in the 90 psi range at that time. Not sure about valve adjustments. This is a flat head engine. Another thing above my pay grade. Fairly sure thermostat is okay based on temperature gauge and water flow in radiator. Oil is most likely contaminated with gas considering the blow by earlier and did notice oil pressure does drop on gauge once warmed up. I checked compression again Saturday cylinders 1,2,3 up to 120 psi. #4 still around 90. Beginning to think my problem is related to that. So here are my questions back to you.
Do you think .055 is about right for a fixed power jet? I am not familiar with that type carb as all others have adjustable needle for power jet. I did not hear back from the carb folk today on availability of a new jet for the TSX400.
What effect would gas contaminated oil have?
Do you think compression difference may be the issue? It may be time for me to get educated in pulling the manifold and looking at valves or should I pull head first? I am not seeing smoke from oil fill tube now.
Would running it on just 2 cylinders with 2 plugs removed show me anything? Just thinking maybe 1 and 4 compared to 2 and 3 as firing order is 1,2,4,3.
Oops missed float question, level I think is set about 1/4" from gasket I will check that before I reassemble. Float is good not leaking. Good test you mentioned I can do that.
Looking forward to your response.