Timing issue?

SQBK so I will assume you have carburation on it since you are able to run a

009? Running a single or two carbs? Too small for this engine maybe? Vacuum leaks around the intake manifold? What color are the spark plug electrodes when you examine them? Fresh air coming in that is cool and not from around the hot engine?

It could be the compression ratio is too high maybe? Excess carbon in the combustion chamber? Regular gas or high octane? What kind of gas is normal there? ;-) Engine getting a little too hot? Are all of the cooling tin pieces in place especially the ones under the cylinders?

Yep, Twin carbies, factory 32PDSIT2. Same carbies as my previous four Type

3,s ( bar the TLE with injection) with no issues so presume thats ok. No vacuum leaks. Spark plugs are powdery black but most of my driving is short runs so chokes on a lot. Because petrol is now unleaded I,m not sure you can use the colour of plugs any more so may not mean much. Not oily though, burns very little oil. ( she marks her spot a bit but one day I,ll put new tube seals in!!!!) No recycling of engine hot air. Engine spotless so no heat build up from the layer of black gunge.Runs on standard fuel, 91-92 rating.All sheet metal bits in place ( I know cos, I,ve taken them all off and resprayed them a nice silver/blue- sad old git arent I!) Muffler off a Kombi. Ta John

AFAIK With that 009 distributor, did you set the mark on the distributor body at #1 plug wire? Is the ignition system developing a strong enough spark? A weak spark may also cause problems.

I forgot to ask if it pings only on acceleration or it pings while cruising. If only on acceleration then yes it might be the advance but it could also be the accelerator system not supplying enough fuel during that stage. If while cruising then I would think jets are too lean, but I know very little about tuning the carbs for performance. Oil bath air cleaners add a little richness to the mixture but since you are running a stock system then I ASSuME you are using an oil bath system. ;-) I will assume that the fresh air travelling to the air cleaner is not blocked, but I would think that might cause a richer mixture or loss of power.

The carbs might shift if loose creating a vacuum leak. So it might be fine at idle but not when the accelerator cable is pulled, shifting the carb and creating a leak.

Carbon build up inside of the combustion chamber might cause pre-ignition by increasing the compression ratio (decreasing space) and by absorbing the fuel. Some will very slowly add some water into the intake system to help clean out the built up carbon. Others might use chemicals.

I might be totally wrong on this so I am sure someone will correct me! JMHO

Only pings on acceleration or load. Going up hill etc. Oil bath cleaner which I,ve soaked mesh in degreaser for an hour or so than washed out. Spotless, also took the bloody paint off!. Carbies tight, all gaskets in. Never heard of the adding water to decarbonise. Anyone know what sort of rates?. She idles smoothly, not too big a flat spot, sits on ~70 mph no problems. About 26 mpg ( automatic)). Cheers John

Maybe the accelerator system is not functioning rich enough. How is the fuel pressure to the carbs? I would probably study up and adjust the jets to richen up the mixture during acceleration and load (mid-range).

adding water to decarbonise

Thanks Dave

Is there the best way to make this on an stock ACVW carburettor system? Where to connect the water intake? Can one use the vacuum connection in the intake manifold below the carb to connect the water or should the water be inserted above the carb?

What is the desired water volume against time for ACVW engine? Like 1 iter in an hour, less or more?

I HAVE NEVER TRIED THIS CONSCIOUSLY! lol I have only heard about others doing this during a tune up procedure.

I guess IF I was going to try it I would use a spray bottle and mist the air above the carb while maintaining a fast idle. I am very cautious about not wanted to hydrolock the engine and cause damage!!! I have read a little about water injection to improve gas mileage, improve emissions and keep things cleaner though. I may experiment with a homemade kit, a variety of different size syringe needles and my old Audi. It stays clean though! ;-)

DO THIS AT YOUR OWN RISK!!!!!

009's have very spotty quality control. The amount of mechanical advance they deliver, therefore cannot be predicted reliabely. Therefore the "standard" timing procedure for an 009 is not a static adjustment. You should be adjusting them at full advance using a stroboscopic timing light. You set them to between 28 and 32 degrees btdc at over 2000 rpm so the full advance is in. If you then want to go back and note the static timing of that particular unit for future points changes so be it.

I,m beginning to think that is probably the answer Gary because nothing else seems reasonable. For a 40 year old engine/automatic that doesnt appear to have been opened up it goes extremely well with very little "expensive noises". By my gradual retarding it I,ve probably got to the ~28 BTDC at max revs which just happens on this one to coincide to about 5 ATDC static. Probably starting a little retarded makes starting a tad easier I would have thought anyway. Being a firm believer in "if it aint broke dont fix it" and it seems happy I think I,ll just leave it. Thanks for advice Gents John

As easy as it is to swap out...and since you know your 009's likes and dislikes so well, personally, I'd give it a go. The benefits of having a working vacuum advance on mileage and smooth off idle transition make an afternoon of tinkering well worthwhile. Nothing ventured, nothing gained. You can always pop the ol' centrfigal only unit back in in 5 minutes time if you dislike the results. I don't think, however, that will be the case.

G,day Bob. Thats basically what I did ( if I understand your point) , took No1 plug out and stuck a dowel down onto piston top and rotated engine so dowel was at TDC on No 1. That coincided exactly with TDC mark in pulley. I think Gary might be right with the 009, just wide manufacturing specs. I suspect the one I put in today was a dual vacuum type that has had a single vacuum unit installed. As far as I know ( sorry old pharts like me dont use AFAIK!) the dual vac retarded the ignition 7.5 deg at start , when idling vacuum,s returned to TDC , then mechanical advanced the rest of way above idle. Putting a single vac advance on that means I have mech and vac advance on a dist designed only for mech advance. Hence pinging. Thats the only thing I can come up with. Might hunt around for another genuine SVDA and see what happens. Cheers John