Returning from holiday ( and whilst packing to go again, smelt petrol when opening up garage. Traced to right carb lever with spring in photo.... is that accelerator pump. How worried should I be and what can be done ? Sent from my SM-A217F using Tapatalk
Probably just needs a new diaphragm and gasket, could be done in situ but much less faff to take the carb off and do it on a bench/dining room table
Next question.....on the underside of the air cleaner "ear" that connects to the right hand carb , there are 2 pipes...a thin one goes to the base of the air filter for, presumably heat....another thicker one goes....where? Sent from my SM-A217F using Tapatalk
I've had trouble with my accelerator pumps which were also prone to dripping. The brass screw adjusts the volume of squirt, and in your case it looks screwed in much too far compared to mine. The only way to check though is to take the top off the carb and attach a length of tubing to the stub where it comes up from the lower half of the carb and measure the flow into a measuring cylinder. Do it ten times then divide the result. Depending on your carbs, the volume per stroke should be 0.7 or 1.4 ml. This is much more easily done on the bench. As to the other question the hose you have in place should attach to the box on the firewall - it's the one with the plastic corrugated air intake pipe on it. The other one goes to the central idling manifold under the air filter.
Having said that, note that connector under the air intake has two pipes on it. Later ones have one plastic and one brass pipe. If you have that, the brass pipe goes to the box on the firewall. As per Snotty, if you're going to swap the diaphragm, you probably should also check the calibration. Bentley explains it all.
New diaphragm fitted....I indeed have 2 pipes under the air intake....brass to firewall or actually into part of air filter box that is where the heat risers comes up .... but I'm still surplus a pipe .... it's about fuel pipe thickness 3-400 mm long ... but I can't find any orifice it can connect to. Engine breather pipe goes to top af air filter, as does pipe for fuel breathers....any ideas ?
This is mine under the air filter. The nylon tube going into a short length of rubber braided hose is how it goes into the idling system. According to Bentley and Haynes it wasn't like that on earlier models.
You should have a vacuum feed which from memory is the pipe you have coming from the balance pipe between the carbs. That goes to one side of the temp sensor in your photo. The other side of the temp sensor goes to the hot air diverter flap on the air cleaner “ear” as you called it.
Will have another look tomorrow at the moment, the thin pipe from the brass connector on the ear goes straight to the hot air diverted flap .
Look at AndyV's photo above - that's where the other one goes - central idling system between the carbs. If it's fallen off air will be sucked into the central idling system so it'll probably idle better when you put it back too. On the other hand, do you know that thermostatic valve even works? Often they don't.
If the themo valve is kaput you can still get them. The VW part number on it is a stock part. It was used on old Golfs etc.
Could that be why the idle tick over, when warm, has increased after it came out of winter hibernation?
