Stuff getting blown out of the carbs

[joestram]

Hi All,

I have noticed lately that when the car is started and running, it will spit something out of the carbies.

It looks like dust that disappears into the atmosphere, however, I suspect it is fuel.

The car also wants to stop when this happens.

Does anyone know what this could be and if it is dangerous (will the car catch on fire or damage the internals). Will a tune just sort it out?

Thanks

Joe

[colcol]

It sounds like the ignition timing could be out, check your ignition timing with a timing light, sometimes the distributor can loosen off, and your timing goes out, and yes, it is dangerous, unburnt fuel spurting out the top of the carby, waiting for a stray flame, i always have this problem with my cars when i rebuild the motor, you time the ignition on a static basis, and when you try and start it, the timing is a bit out and its hard to start, but when it fires, you get flames out the carby's, then you warm it up and time it, the only other thing i can think off is a leaky needle and seat in the carby, spilling too much fuel into the carby, but it would be running dreadfull, Colin.

[Stuart Thomson]

Also could be a lack of fuel pressure regulation.  Are you still running the standard fuel filter?

Cheers
Stuart

[joestram]

Hi  guys,
Sorry kind of forgot I posted this.
Hi Stuart - Not sure about the fuel filter. I know the car has had work done on the carbs and it now runs an electronic fuel pump but not sure about the filter.
Hi Colin, I had a feeling it may have been that as i was messing aound with the spark plug leads a couple weekemds before that. I might call around a mobile mechanic to time it for me unless someone here wants to it for a slab of their favourite beer haha.
Could it be the wrong type of fuel? I did fill the tank with optimax the last time i drove it. Should I throw some lead replacement in?
Thanks
Joe

[MD]

Electronic fuel pumps come in various forms. Hi pressure for injection and low pressure for carburration. In either case the supply to the carbies requires pressure regulation to ensure a constant low pressure supply. A high pressure will cause running problems.

I think the carbies only need a 2-3 PSI (the actual figure escapes me ATMO)

[joestram]

Hi guys,

Finally had a chance to check it once more and it is actually spitting flames out of the carbs.

How do I change timing?

Would crossing over the spark leads cause this?

And can I damge the valves by messing around here?

Thanks

Joe

[Cool Jesus]

Type of fuel isn't the issue, the 116's were made for unleaded, unless you chucked diesel in it
Definately sounds like yoiu may have crossed your leads. If this is all thats happened, your valves won't have suffered for it. What's happeneing is that an out of time spark is occuring when the inlet valve is open and receiving some sweet fuel, the flame then travels out of the piston via the inlet valve and up through throttle body, hence cool flame thrower

Timing should run from cylinders 1-3-4-2. I believe the no.1 lead is towards the front of the dizzy cap, maybe even of on a slight 45 angle closer to the block (at the front).

To be certain you could do the following - You'll need to move your crank manually with either a large socket on the front of the crank shaft (turning clockwise) or place it into 3rd/4th or reverse gear and push the car until you get no.1 piston up near top dead centre. Don't spin crank CCW, you could jump timing chain teeth which will cause worse timing issues.

Remove cam cover and no.1 spark plug, loosing others will make cranking much easier as your not fighting the compression stroke. TDC is with the piston at the top of its stroke, so should be visible from the spark plug hole and both no.1 cam lobes should be pointing to each other. Keep turning until you reach this scenario. The cams also have a timing mark punched into them which will line up on the first cam clamp at the front, there'll be a little notch on the backside of the clamp which is transposed onto the cam. When lined up, cam lobes pointing at each other you have TDC and spark firing for no. 1 cylinder. Move crank CW and watch which way the dizzy rotor spins (can't remember off hand), however the next firing position is cylinder 3, after that attach your 4th and 2nd lead appropriately and timing should be very close to at least run the engine. Minor adjustments are then performed by loosening dizzy clamp and turning left or right to advance or retard the spark firing point.

[Sheldon McIntosh]

Sounds like the same problem I had with the little shitbox Mario Speedwagon, see this post...  http://www.alfaclubvic.org.au/forum/index.php?topic=4898.msg33977#msg33977

Setting valve clearances to spec (and replacing a worn cam) fixed it right up.

[joestram]

Hi guys,

Thanks for the detailed comments Cool Jesus and for the link Sheldon.

I hope it is not the cams as I believe they were just put in a year or so ago (PACE cams).

Can someone please confirm if this is the correct layout for the spark leads.


http://imageshack.us/a/img254/1151/alfamotor.jpg

Hi Cool Jesus, can you please let me know what TDC (it's probably obvious but I haven't picked it up yet).

Thanks guys.

Joe

[colcol]

If the leads were wrong, it would hardly run, my 33 blows fuel thru the intake, when the air cleaner is off, and if the timing is way out, you get some flame as well, always happens after engine rebuild or distributor is removed and timing not set, you need to time distributor with timing light, and start from there, and when its fixed, get a marker and label the leads and distributor, Colin.

[Cool Jesus]

TDC is Top Dead Centre, ie when the piston reaches the very top of its stroke.

The best way to be sure is to check the relationship between the cam lobe, cam markings and TDC of no 1 piston. The leads look to be in the right firing order, however you say your issue has surfaced only recently. 

As Col mentioned, could you possibly have a sticky/leaky metering valve in the carburetors and you're flooding the engine? What do your spark plugs say? Do you know if the carbies have been cleaned, serviced etc. at any time?

[Darryl]

Unless I'm crosseyed those leads are wrong - swap 2,3.

[giulia_veloce]

Looks OK to me= 1342

Sounds like the idle jets are too small,or the idle mixure screws need winding out another turn.
Spitting is usually a leaness.
Could also be retarded ignition timing.
Usually start with the easy things like point gap,ignition timing,carby balance + idle mixtures.
Idle mixtures only to be done at operating temperature .
How many turns out are the mixture screws ?
Compression test ?
Just start with the basics.
Your explanation (spitting like dust), tells me the idle jets need the next size up,,like 55 to-57-58
Very common on Alfettas
Get it verified by an Alfa Specialist who knows carbys. (like me)

Guys,,we can only go by what we are told.
What was mentioned sounds like the above= leaness

Robert

[joestram]

Hi guys,

Thanks for the replies.

Robert, thanks for those details. I was told by the previous owner that the car has the largest pace street cams and the carbs were rejetted to 52mm and the work was done by a Lloyd @ Sirius in SA.

Not sure if that means the idle jets were done as well.

If anyone is good with this sort of stuff in south eastern suburbs of Melb and can do a house call to help (for a fee) can you please pm me.

Thanks guys.

Joe

[Sheldon McIntosh]

Have you got a standard airbox/filter you can put on it (at least just to test) ?  Trumpets look great but are not necessarily that great for street driveability unless set up correctly.  Let alone the filtering issues....