S2a refuses to idle

Richard, The exact thing is happening to mine except for the tickover. I replaced the Exhaust and manifold and can see or hear no obvious leaks. Has your water temp changed since it started Popping?Mine is running cooler and going to reset the carb today to see if it makes a difference..

Try running the engine at fast tickover and blocking the air inlet with a rag so it stalls to clear any blockages..

Have you recently cleaned the air filter too much oil in it may cause this...

Adrian Ford

It could be a bit of lint in a jet It could be some water in the bowl It could be you are running a bit retarded It could be the points are sh***ed Could be an air leak Or any combination....

Good Luck

So Adrian Ford was, like

Nope - runs cool as before.

Haven't heard this one for a long time - good idea, I'll give it a try. (Except that fast tickover is what it won't do. I can set the tickover high, start it in the cab and it runs fast, but by the time I get round to the business end it has died again.)

Yes, recent full service before an offroading weekend, but that was back in January. Has run fine until a couple of days ago.

Thanks for the ideas.

In message , Richard Brookman writes

I have had some trouble with idle speed on my s3. Set everything up lovely and it would run fine then suddenly (usually after being banged around on a forestry road) it would run unevenly. Blamed it on all sorts of stuff. It has a new exhaust, new dizzy and no apparent air leaks. What I did notice while playing with the mixture screw was a very small sound coming from the crank case breather valve near the carburettor. On inspection I discovered the rubber diaphragm therein has been replaced with a circle of inner tube! This didn't look as though it would seal too well and would provide an entry point for air in the inlet tract. Removing the plugs indicated that it had been running pretty lean. Might be worth checking this. (If s2a's have such thing)

Does anyone know where I could get a diaphragm online for this thing? The part number for the whole unit is rtc6855 but I don't seem to be bale to find the number for the diaphragm itself.

Sounds like points to me. Re-gap or replace.

HTH, Roy.

I've seen 360635 quoted as the diaphragm part number. I cannot confirm the accuracy of that information.

Sounds like a classic case of Zenith Warp to me, try filling in the jet as recommended

I fitted a new "Zenith" pattern carb (from Craddocks) about 2000 miles ago. Since then she has run perfectly, with plenty of power, a smooth idle hot or cold, and economy improved from 14mpg to about 20. So far, so good.

Yesterday, the idle speed dropped to almost zero (I had it set to where the charge light would just flicker) and today she refuses to idle at all. Increasing the idle speed a fraction kills the engine dead. Moving the idle mixture screw in and out makes no difference (until you take it right out, when the engine stops, obviously). Normal speeds, the engine runs fine as before. Nothing loose, fallen off or obviously broken, vacuum advance pipe is in place, and I've done nothing to it except drive around. I'm guessing either an air leak on the inlet side or a blocked idle jet, but I thought I'd see if anyone had any bright ideas.

One other symptom, which has developed at the same time: the exhaust has always popped a bit on a steep downhill on my way back from work, but now it's popping regularly and loudly even slowing down for junctions. This suggests an air leak on the exhaust side. New exhaust fitted about 2000 miles ago, but again no problems until yesterday.

Anyone put two and two together and make SQRT(25)? I'll strip and clean the carb at the weekend otherwise, but since it was 100% OK before yesterday I reckon it must be something silly.

Thanks

So Austin Shackles was, like

Thanks to everyone for the replies. First free weekend in months, so I planned to have a good look yesterday. Went for a short run first to do a few errands, and - ding - it's cured itself. Warmed it up, reset the idle mixture and speed, and it's as good as new. Blocked jet looks like the most likely contender. Coconut to those who suggested that. (I've filed all the other ideas for future reference. Cheers.)

Land Rovers! Doh. Love 'em.