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`61 Giulietta Spider, `65 Giulia Ti 1750, `69 GT junior 1600, `73 Spider 2000, `74 GTV 2000, `98 156
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What`s your starting proceedure? What I do is give the carbs 2 or 3 pumps before turning over-this will initially start the engine but it may die (lack of fuel until pump fills float chamber). I never have used the choke even with a frost in winter which I can`t imagine you would encounter. Avoid over pumping carbs, that`s why no more than 3 pumps as you are likely to flood engine.
It is important to make sure ignition timing correct and that includes points adjustment to correct gap/dwell angle. It also makes a great deal of difference putting a sports coil on as it seems to fire the engine quicker than the standard coil-my theory being that it has the grunt to fire a less than ideal air/fuel mixture at cold start.
 

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`61 Giulietta Spider, `65 Giulia Ti 1750, `69 GT junior 1600, `73 Spider 2000, `74 GTV 2000, `98 156
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Love the name of that product. Imagine it`s Australasia market only though.
 

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Discussion Starter · #8 ·
I usually turn the ignition key and gently pump the gas pedal at the same time. I always get it going but it requires a bit of time. The battery is an Odyssey PC925 with a cranking capacity between 765 and 925 cranking amps.

I hadn't considered a sports coil however. There must be a way to get the car to start first time every time. Are 105 GTVs typically difficult to start?

Still I wonder what differences there could be between a hot and cold engine making starting difficult. What exactly is it about cold air or a cold engine temp.
 

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It sounds to me like your carburetors get dry, especially in case you have a strong spark ( i guess so as you say you have fitted a 123 electronic ignition). Maybe your carburetors' rubber mounts are cracked allowing air to enter, forcing fuel back to the fuel tank. Another option is that your fuel pump may have started dying...
 

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I have the same problem with the same car, the only difference is that I am running dellortos. The car was fine when I bought it 10 years ago but developed this problem a few years ago. Hot starting is instantaneous but the longer I leave the car the longer it takes to start. I am sure it is not cranking speed as in the warm weather it is noticeably quicker but makes no difference to starting. I have changed every ignition component. Carb mounts are good and carbs professionally rebuilt and set up. New pump made no difference. I am however 99% sure it is a fuelling issue. On all my previous Alfas to get them started needed nothing more than 4 pumps on the throttle and away they would fire - maybe a bit of choke in the winter months. Now pumping makes no difference and it is just cranking with choke on that does it - maybe 2 or 3 minutes. Eventually it fires but will die if you touch the throttle (sort of suggests that fuel hasn't got high enough in the float chamber to reach the accelerator pump?). My suspicion is that the fuel lines are syphoning back and the fuel in the carbs is evaporating (as I doubt the fuel can syphon back past the needle valves). My next step is to change the regulator/filter as that is the only thing left that is unchanged and perhaps there are some valve somewhere that are leaking. I am surprised that fuel evaporates so readily from the carbs though.

Maybe some of this is familiar - I know I am not the only one with this problem and I am not aware of any fixes for it - most owners just live with it. It is more annoying on a car that is used infrequently knowing how much cranking you have to do just to get it running.
 

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The actual problem is fuel evaporation within the float chamber. A 123 ignition system actually only replaces the points and gives a very small advantage in spark intensity due to a consistent rise time (dwell) for the coil and consistent time the engine gets its spark. A better coil gives a better spark during this cranking time as the starter motor robs quite a bit of current-remember the engine is also a lot harder to actually turn over when the engine is cold.
There is actually little you can do to the carbs to overcome this apart from checking them over and making sure everything is correct-things like the needle and seats in the float chambers, replacement of the float chamber gaskets and the idle mixture settings, accel pump jet settings etc are as they should be but greatest improvement is to ensure the starter motor is not robbing too much power ( a relay in the starter circuit is highly recommended both for switch protection and to ensure proper current). It would also pay to check the starter solenoid points and the brushes.
You should also give those three pumps BEFORE you turn the engine over not as you turn the key.
 

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When it's cold work the throttles and using a mirror look down the throat and see if your acellarator pumps are giving you a shot of gas, should be able to smell it too. If no gas, no start. If no gas take the wing nut off and see if the bowls are full of gas, if not then it's got to be a fuel supply problem. If you see gas whilst working the throttle then start looking at spark issues, fouled plugs etc. Much eaiser to start a semi fouled plug when hot than cold.
 

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The actual problem is fuel evaporation within the float chamber. A 123 ignition system actually only replaces the points and gives a very small advantage in spark intensity due to a consistent rise time (dwell) for the coil and consistent time the engine gets its spark. A better coil gives a better spark during this cranking time as the starter motor robs quite a bit of current-remember the engine is also a lot harder to actually turn over when the engine is cold.
There is actually little you can do to the carbs to overcome this apart from checking them over and making sure everything is correct-things like the needle and seats in the float chambers, replacement of the float chamber gaskets and the idle mixture settings, accel pump jet settings etc are as they should be but greatest improvement is to ensure the starter motor is not robbing too much power ( a relay in the starter circuit is highly recommended both for switch protection and to ensure proper current). It would also pay to check the starter solenoid points and the brushes.
You should also give those three pumps BEFORE you turn the engine over not as you turn the key.
I agree - plus modern (Oz) unleaded fuels are quite different from the old leaded fuels these engines were designed around. Modern cars make more adjustments with their electronics to ignition timing etc than is possible with 1970's tech. Also they evaporate some components (aromatics) faster.

A fuel knowledgable friend of mine suggested some years ago that unleaded was a large part of the same problem on my 1973 2000. As an experiment we dumped some (leaded) Avgas into it - fired up 1st or 2nd crank when cold, compared to "eventually" on ULP.
 

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Discussion Starter · #16 ·
Yes my thoughts have been centered on the carby. It does need an overhaul for sure.

ducantibruce I thought these cars were designed to run on unleaded though. Still I do acknowledge that there are probably other ways that modern fuels differ. I am wondering if using something like BP Ultimate 98 octane would make a difference?
 

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<snip>ducantibruce I thought these cars were designed to run on unleaded though. Still I do acknowledge that there are probably other ways that modern fuels differ. I am wondering if using something like BP Ultimate 98 octane would make a difference?
Designed to run on unleaded, in that they have hardened valve seats. Lead is an upper cylinder lubricant as well as knock inhibitor.

Modern ULPs have a vast number of additives to achieve the knock inhibitor properties of leaded fuels. Most of those additives are highly volatile. They also mean that the combustion process changes quite a lot between a cold & hot engine. Modern electronics use ambient as well as engine temp in addition to a whole bunch of other parameters to determine appropriate ignition timing. Our poor old Marelli/Bosch distributors can't do that.
Timing that's optimised for hot running will be less than optimal for cold starting.

Modern ULPs additives are also quite volatile in that they evaporate quite quickly. Modern EFI's are pretty well air tight and don't allow much evaporation. Dellortos & Webers are anything but airtight. Parked hot a lot of the volatile compounds evaporate from the carbs quite quickly - leaving a vaguely fuel like fluid. Part of the long starting process is getting fresh fuel into the engine to replace the old stale stuff.

The guy who gave me this info (about 10 years ago) was engaged in developing tests to check for mandated retail pump fuels in motorsport. His basic recommendation was that modern fuels were so variable over time (same brand/batch even as it aged) that it was next to impossible to test for cheating & proposed a max octane rating as the best derterminant.

At that time, & with the fuels tested the BP was most consistant (& therefore probably least volatile) whilst Shell was most variable & volatile.

The higher octane ULPs have more volatiles than the lower octanes & will probably (if I'm right) make the problem worse. FWIW I run the BP ultra 98 for various reasons & put up with the harder starting when cold (which is worse the longer the car has been parked(up to about a week))

None of this is to say your 105 should be really hard to start cold, just that it will almost always take a bit more than when it's warmed up
 

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Not sure if this is relevant as you don't mention the year of your GTV but I was told once by a specialist that for Euro market cars early 2000GTV's and Spider 2000's were fitted with a weaker starter motor. Apparently this was upgraded around '74.

Had my '72 spider fitted with the 'upgraded' one and it was definitely faster starting. The original was painfully weak if I recall.
 

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Yes my thoughts have been centered on the carby. It does need an overhaul for sure.

ducantibruce I thought these cars were designed to run on unleaded though. Still I do acknowledge that there are probably other ways that modern fuels differ. I am wondering if using something like BP Ultimate 98 octane would make a difference?
Have a look at the things that I have done that have NOT cured my starting problem. I went to the expense of having the carbs professionally re-built and the jetting checked, rolling road tuned etc. If you are doing as much cranking as I am then I am not convinced by it being caused by the difference in modern fuel. 2 or 3 minutes cranking is an awful lot of fuel just to fill the float chamber and suggests the fuel line is going dry too. Most people's Bertones start reasonably it is just a small minority that don't - surely if it was a fuel problem then the problem would be more widespread? There are some other threads about this problem too (on other forums as well - Alfaowner I think). I am not convince by the starter cranking either as I get a much higher cranking speed in the summer but no difference in the starting - I get a huge healthy spark as well so I am sure it is fuel.
 
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