1941 9N starts, but dies after about 5 minutes

After years of excellent starting behavior, my 9N suddenly wouldn't start at all.
I removed and reconditioned the distributor and the carb. At first it then would start and run with the choke pulled half-way, but only for a few minutes. Sparking tests seem OK.
I then removed the inline gas filter and leaky hose and installed a new (aarrgh) sediment bowl-w/valve and a steel gasline and new in-carb connector-filter. It was a pain minimizing the leak thru the sediment bowl gasket, but it now [u:a92960ab68]seems[/u:a92960ab68] manageable(?). My three attempts with different O-rings failed to be any better than (non-cork) material.
It now runs long enough (without any constant choking) and sounds good enough to do main needle & idle needle adjustments, initially responding nicely to changes in the throttle level. But before it is about to die (gas-starved?), there is no response at all to throttle-advancing.
I have measured the gas flow out of the carb bottom-drain to be close to 9 oz/min over 30 minutes, and the flow rate directly from the gasline to be close to 15 oz/min, also over 30 minutes, with very similar results over 3 minutes.
During the flows, there did not seem to be any air-bubbles forming in the gasline, although I could barely see a possible bubble in the top of the sediment bowl, but that didn't [u:a92960ab68]seem[/u:a92960ab68] to interfere with the flow. The filters have remained clear.
When I removed the carb again, I readjusted the float to be 1/4 inch offset from the metal [u:a92960ab68]surface[/u:a92960ab68] for the gasket rather from the [u:a92960ab68]gasket surface[/u:a92960ab68] of the material. The starting behavior has still been the same.
I am thoroughly puzzled and would appreciate any suggestions.

See tip # 13. Do both tests as soon as
the tractor stops running, not 5 minutes
later.

Post back with results.
75 Tips

Learn to perform true root cause problem solving methods for issues, and not simply start swapping out parts with new. You may end up with whole bunch of new parts and the issue still remains (that should tell you something) or, you inadvertently stumble across (rarely) the issue, which you didn't. What is a 'reconditioned distributor'? Did you do a complete, correct tune-up with points set correctly and unit tested before mounting? Did you mount the distributor correctly? If it was mounted incorrectly, off by 180?, it will bust the housing nearest the cam & weights, quit working, and thus rendering the housing as junk. Like Bruce(VA) said, when it stops running, perform the spark and fuel test first. That will get you in the ballpark on the root cause. If no spark, it's in the wiring/distributor. If it's due to a failed fuel flow test, there are a few reasons why. Having the proper parts is a huge part of the equation. Never use rubber, plastic, copper, or nylon as a fuel line. They make correctly pre-bent 1/4" fuel lines well worth the cost. But, I doubt if they were related to your issues. You also did not need an extra in-line fuel filter there are three in the OEM system as it is. BTW, the carb float is set WITH the gasket on, and that isn't your problem either. The OEM Operator's Manual states setting float gage is to be set as .260" GO, and .297" NO-GO at the nearest point. That means at the point nearest the float hinge. Replacing the fuel sediment bulb with new wasn?t your issue as you found out as well. Cleaning the two bulb screens would be one cause of plugged fuel flow. The third is in the carb fuel line inlet with a brass elbow and attached fine mesh screen. BTW ? you only need to replace the Fuel Sediment Bulb Valve, it?s the only wear part on the Bulb assembly. It is a $6 part but some will geek you for $10 or more so it matters where you buy from. The Valve Stem, p/n APN-9194, has a OGR rubber seal on it that gets chewed up over time of constant opening and closing. The second major cause of bulb fuel leaks is due to mucked up threads on the unit or line. Threads are UNS (Unified National Special) 7/16-24 made for fuel and brake lines. Always hand-start the fittings and do not attempt to use an incorrect tap or die to repair with. You should always do the spark test first, for safety, so as not to be arcing around spilt gas by doing the fuel flow test first. Always do tests with a cold engine.

FORD FRONT MOUNT DISTRIBUTOR ? WHAT HAPPENS WHEN MOUNTED 180? OFF:

DIRTY IN-LINE CARB FILTER ON FUEL INLET BRASS ELBOW:

SEDIMENT BULB VALVE STEM ?P/N APN-9194:


[i:654c4848f0][b:654c4848f0]<font size="4">Tim *PloughNman* Daley(MI)</font>[/b:654c4848f0][/i:654c4848f0]<table width="100" border="1" cellpadding="0" cellspacing="0" bordercolor="#000000"><tr><td height="25" colspan="2" bgcolor="#CC0000"></td></tr><tr><td></td><td></td></tr></table>

Are your flow test results a typo? Did you mean 3 minutes not 30? You should get a pint (16 oz.) in 3 minutes. Have you tried loosening or removing the gas cap during your flow test or even while running? The vent at the top of the gas tank might me plugged. It's hard to see without removing the tank. The float adjustment should be from the gasket surface, but that's not your problem right now. Like Bruce and Tim said, it's a lot cheaper to trouble shoot the problem rather that taking a shotgun approach. Then you said the spark SEEMS O.K. Are you getting a good strong spark to jump 1/4 inch? I don't see where you said anything about the spark plugs. How do they look?