Z120 throttle response

[2011dandd]

Hello everyone

Hope I can lean on your experience once again please.

I’m not entirely happy with the throttle response on the old girl. Unless done slowly if increasing the revs fast it sounds like it could stall occasionally or spits and stutters a bit before picking up.

These are the facts,
Idles absolutely beautifully
Marvel Carb is as clean as a whistle
Timing is at complete tdc as far as I know (that’s the setting I fitted the dizzy)
Occasionally coughs a bit

wondered what you folks suggest? More fuel on main jet or adjust the dizzy?

Thanks in advance, Dan

 

[Jim.ME]

TDC is a base timing point. Your operator's or service manual should give specs to check the distributor advance when the engine is running with a timing light. If you have not checked the advance with the engine running, you should check it with a light and adjust the timing to match the high idle spec with the engine running, before changing the carb.

 

[Tom H.]

Just checked manual, timing is 7 degrees before.

 

[Jim.ME]

TE 20 service manual shows 0 (TDC) at 400 rpm, 29 degrees BTDC at 2000 rpm.

TO-20 shows 7 BTDC at 400 rpm, 21 BTDC at 1000 rpm, and 31 BTDC at 2000 rpm.

You have posted about a TE 20 before, so I am guessing this is what you are working on. Always best to give the tractor model as well as the engine.