International Lancia Forums

After removing a small wood splinter from one of the jets, and cleaning and re-gapping the plugs, my new (to me) Fulvia is running quite well. Revs smoothly up to 6,000 and pulls strongly. However the idle is still a bit lumpy, not too bad, but not as smooth as I'd like it to be.

I'm familiar with Weber 40IDFs from my Fiats, but haven't been able to find much information on the Solex PHH 35 carbs. I took a picture of what I believe to be the idle adjustment screws:

http://www.petercripps.com/Lancia/Solex_screws.jpg

I think the screw going through the metal strip with '808...' is the idle air volume adjustment? This would be equivalent to the Weber air bleed screw, yes? So does that mean that the recessed slotted screw, just below it, and slightly to the left, is the idle mixture adjustment?

Incidentally, I do have a synchrometer and it shows fairly even balance between all 4 cylinders, so I don't think things are too far out.

Thanks,

Peter

The screws through the metal plate are the idle mixture adjust screws. CW is leaner, CCW is richer.
The recessed ones are the by pass screws and best not touched.

Thanks, Huib! Also please see e-mail regarding CDs.

Peter

You are welcome.

A common problem with the Solexes is wear on the spindles and their bearing and on the butterfly valves and the barrel. If this is the case, you are not going to win any idle contests because of the air leaks.

If you have acces to a machine shop you can fix it by boring the barrels to slight oversize till they are perfectly round again. Then machine new 13 degree valves to the new size. Looks complicated to get the 13 degrees but it is really simple.

Then machine new oversize spindles or put bushes in the carb bodies. It is some time ago I did this. If I would have to do it again today I would experiment with plastic valves (POM or similar) instead of brass.