Many thanks gents for your replies and info- very much appreciated (as always).
Full disclosure up front: While my son and I have worked on and restored some old Tecumseh L-Heads, they are not "in our wheelhouse" like the Briggs of the same era (mid 1960s-late early 1980s). I think that we are "fairly" competent and experienced with them, however.
Here is why I posed the question...
I am getting contradictory results with the idle and high speed screw settings as they relate to the performance of the engine.
I adjusted both the idle and high main screws to get the best overall performance as per the Tecumseh manual.
Idle screw is opened about 2/3 turn out and high speed is opened about 1/2 turn out. (My Tecumseh 3-11 HP L-Head manual states that 1 turn out for both is the "starting point" on these diaphragm carbs to get it to run, then adjust in or out from there, which we did)
1. On cold start the choke seems kind of lean- taking 3-4 pulls to get it to fire (I'm in So Cal- not THAT cold here!).
2. After the engine has started and warmed up it runs GREAT- nice smooth low rpm idle and good performance throughout the upper rpm range.
3. If I shut the engine off and try to restart after a couple of minutes it will start and run on only one pull.
4. If I wait much longer than that (engine still very warm to the touch) I will need to choke it to get it to fire- THAT seems like lean condition to me? If I try turning out (opening) the high speed screw at all performance really degrades.
5. Only 1/2 turn out for the high speed screw seems odd to me? Every other Tecumseh I've owned was 1- 1.25 turns out
Here's the background on this engine;
This was a full tear down, cleaning, inspection (measure for any reject sizes) and rebuild:
Rebore with new .020" O/S piston/rings set
New rod
New valves- they were lapped and lash was set at .007" for each (My Tecumseh manual states to set from .004-.008)
New head
New crankcase oil seals (both sides)
Carb was taken apart , all orifices probed and cleaned in ultrasonic, followed by carb spray. Carb was fully rebuilt including new diaphragm (put on the correct way!)
New points/condenser
Engine re-timed (Thank you Brian!
)
New NGK spark plug
New air cleaner element
Fuel tank cleaned and in-line fuel filter installed
Does this added information give anyone some other/additional ideas?
Michael