My Solex 28-32 carb floods and stalls on idle. The petrol comes out the small brass pipe into the second barrel. Could it be the float or neddle and seat.

could well be the float or needle valve. first thing to do is to take it out and see if the float actually floats or not.

Check also accelerator pump diagraph (what was the word, thing that may get hole is under lid with 4 screws and pumps fuel forward?)
If that gets hole fuel might get to carb trought that small pipe, but it should go also to other barrel as they share fuel channel.

Needle valve is something what got stuck on mine and fuel was coming out from every hole of carb to every direction, not very nice thing to happen.

I hear also that this float is quite general fault so good to check it too, it should weight 4 grams or something, better check Haynes for proper weight, should be very light.

Thanks to both
I have now ordered a service kit for the carburettor (cost about £25 including post) and that includes a new needle and seat. The dealer said that this float is hard to get so I hope its not the float. Jack

Jani means diaphragm, of the accel pump jet. If it is the float, scrappies have loads of those carbs, they are on a load of renaults.

you should put the float on a letter scale.

correct weight is 6 grams. allowed tolerance = 1 gram.


my float was around 12-13 grams. car ran really cr#ppy..

Did you buy a new one? where? Cost?

Volvo still do them as part of a repair kit for the 1.7.... list price is £91+VAT though... I've got the part number indoors if you are keen, I got a lucky find on ebay with one.

thats horribly expensive!! i got one from renault at 34 euros


thats about 26/27 pounds?

I posted once a link to offtopic, carurettorexperts or what that was, they had almost any part to any carb.

Float is 35€ here in Finland, not from Volvo but from carb shop.

Ok, I got my repair kit from Carburetor Exchange for £22. On the weekend I pulled the carby apart and replaced the bits and pieces. The float weighted 12g so I will now get one of these from Renault. Now the question:
The purple wire that goes to the idle jet solenoid also goes to another electrical component directly under it.
On examination this component resembles an air cut off valve. It has a magnetic disc about 12mm in diameter - mine broken into 3 pieces. But the port that it covers was blanked off. Any idea what this is meant to do?
Jack

The thingy under the idle jet soleniod is a pre-heater, when you put it back together make sure you put it round the right way, else it keeps blowing hte fuse as it'll short to the carb chassis....

Mine still isn't in the right place, hence I also know the car runs ok without it whilst you get hold of the bits It's on the to-do list!

its a thermistor, meant to heat up the part of the carburettor directly in contact with it. this is done to prevent freezing up of water vapour in the low end throttle range. some models also have a piece of coolant tubing attached to that point.

afaik the thermistor is not available anymore...

Guys, you are brilliant. There is no heating element in the thing and so it just shorts out on the carb body. Therefore the fuse blows therefore the idle solenoid doesn't work and the engine doesn't slow run. I will test the solenoid tonight.

Yeah, thats what mine was doing, I just need to put it together as it should be I hope, but mine has been set up without it anyway. Took me a while to wonder why I was having a job setting it up, until I notice the rear wiper and ciggy lighter socket didn't work and therefore the idle solenoid must have been shut