Zenith 321F7 carb.

[edwin]

Hi all. After having the head gasket fitted, water pump and push rods being attended to, Ronnie the Renault is back with me. It took7 months to get it done.
The engine is smooth , quiet and sounds great. However as you accelerate there is an initial hesitation. The revs drop too low when you take your foot off, tick over is lumpy, not quite one plug not working.
I thought I’d look at the carb, and adjusted the accelerator to get better tick over. OK so far. Then thought I’d look at mixture. No reference to 321F7 in Haynes. After consulting this amazing forum back catalogue i found a pic of the mixture screw location. I checked mine and all was the same, but there was no mixture screw in place. I have had the car 9 years, and not missed it. What do I’d now ?
Where would I get a mixture screw for a 40 year old carburettor made in Spain. How come the car has run so well without it, or has it recently fallen out, or disappeared in the engine work?
Help!

 

[Andy McGhee]

De Marco parts do a repair kit for the 32IF7 (it's an 'I' rather than a '1', by the way).
I would get in touch giving them the exact carb model details - they'll know if it's right, and they might sell the mixture screw on its own.

Carburetor Repair Kit Zenith 32 IF7 for Renault 4, R5 and R12

Purchase the Zenith 32 IF7 carburetor repair kit. High-quality product available at De Marco Parts. Fast and secure shipping.

www.demarcoparts.com

Could the tip of the mixture screw still be inside the carburettor?

 

[André4Renaults]

It took7 months to get it done.
The engine is smooth , quiet and sounds great. However as you accelerate there is an initial hesitation.

Just a thought, but are you sure the ignition's functioning correctly? If there's a "hiccup" as you depress the accelerator the problem may lie with a worn out condenser/capacitor. On tick-over the capacitor can handle the current, but as the revs increase the rapid loading and unloading becomes too much for a worn capacitor/condenser. In the 7 months the car's stood perhaps the faces of the points have become coated with a small amount of rust, so perhaps re-facing the points might help.

 

[angel]

Are you sure you are looking at the right point for the mixture screw? On the 32IF7 it's at the front of the carburettor mounting flange / butterfly housing. And it's fully recessed in its hole, there is no screw head visible.

 

[edwin]

Thank you all for your advice. Angel your comment interests me. I will look at that tomorrow. I did not know the mixture screw was recessed into the body of the card. The site is on the front elevation, nearest the front of the car, but set back from the front face of the carb in a very inaccessible place that is difficult to see. There are hot bits of engine all about your face as you try and see the location. I will look at it when the car is cold. Will also check the points. I put a new capacitor on a few years ago. Thank you all. Will act on your advice and report back shortly.