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bachelier
05-19-2013, 02:00 PM
Hi everyone,

I bought a new Zenith 36 IVE copy on ebay. After installation and calibration I notice huge hesitation when I run at full throttle, pedal fully push to the floor. After maybe 30 secondes of full throttle the hesitation begins and if I continue, the engine cut off but if I decelerate it returns to normal. It's like petrol starvation. I put a new a petrol pump and filter and I screwed out the mixture screw; no difference. I'm goona check the tappet valve adjustment and the gap in the distributor. Someone has ideas?

Revtor
05-19-2013, 02:31 PM
check your fuel filter?





Hi everyone,

I bought a new Zenith 36 IVE copy on ebay. After installation and calibration I notice huge hesitation when I run at full throttle, pedal fully push to the floor. After maybe 30 secondes of full throttle the hesitation begins and if I continue, the engine cut off but if I decelerate it returns to normal. It's like petrol starvation. I put a new a petrol pump and filter and I screwed out the mixture screw; no difference. I'm goona check the tappet valve adjustment and the gap in the distributor. Someone has ideas?

I Leak Oil
05-19-2013, 02:56 PM
I had very poor luck with the zenith clone I tried a few years back. 3 months and the floats had basically swollen so much they split and wedged against the body of the bowl. Not saying that this is your particular problem but just conveying my poor experience with the aftermarket patterned carb.

bachelier
05-19-2013, 05:10 PM
I'm thinking to go back with Rochester.

bachelier
05-19-2013, 05:11 PM
New fuel filter and nothing has improved.

jonnyc
05-20-2013, 06:19 AM
I suffered for about a year with the pile of Zeniths I inherited when I got my Series 3. I switched to a Rochester about 13 years ago and never even thought about going back or getting a Weber. They aren't perfect, but Rochesters are simple to fix and have plenty of power at low an high end.

bachelier
05-20-2013, 11:18 AM
I've cleaned the spark plugs and I srewed out the mixture screw on the carb a little bit to have it more rich and I found the right spot. No more hesitations! I hoe it will like that for a while. Question : if I go full throttle with the foot on the floor do the acceleration pump in the carb is always working at that speed?

SafeAirOne
05-20-2013, 11:43 AM
The accelerator pump is a one-shot deal to keep the engine running till the carb/vacuum/fuel flow can catch up when your foot depresses the accelerator pedal and opens up the throttle valve.

Here's a pretty good explanation:

http://www.jaimekop.com/CarbManual/Page06-07/