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Discussion Starter #1
Hi Guys;

I am having a problem with cold starting. I have a mildly tuned 2l with 1mm oversized valves from centerline and street performance cams from IAP. I was running the stock jets and ventures for a 2l with DCOE32 weber carbs. Initially, I could barely get the car to start at all, and it had a horrible flat spot in progression. I upsized the idle jets one size and the problem almost went away. If I am critical, I would say it is still a tiny bit lean right off of idle. The problem I have is the engine is still very difficult to cold start. Even with the choke on and lots of cranking, it will barely sputter to life, and then I have to nurse it along for 5 min. until it warms up. After that, i put the choke back in and it runs and idles fine.

My mechanic thinks the problem may be related to a starter jet that is too small. I can't find any information on the sizing of starter jets for these engines. I think I probably need to go up a bit more on the idle jet. What do you think?

Any help is appreciated :)
 

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What ignition system are you using? Strong sparks help a lot with Webers.
 

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Hmm, sounds like too much choke to me. I hardly ever use mine even when its cold. Turn the ignition on and let the fuel pump build up pressure, two or three pumps of the gas, turn it over and it should start, IF, the rest of the ignition and starting system is in order. Remember, this isn't fuel injection so it won't idle well until you get a little of the cold off the engine. and find someone who has experience with Weber carbs. :)
 

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Discussion Starter #4
more info

Thanks guys. I am running golden lodge 2hl plugs, a bosch blue coil, a remapped distributor. all were new with the engine rebuild. Wire were new as well.

I have tried starting with or without the choke, and with seems slightly better, but still bad.

Any other ideas?

Thanks again for your help?:)
 

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Is the timing set correctly? Try to advance it just a touch when the engine is cold and see if that helps. Does the engine start over-rich (i.e. lots of black smoke?) Are the carb floats leaking (drips into the carb throats when you check with a light or a mirror, not while cranking)? Do you get a good shot of fuel when you open the throttles or does the shot of fuel diminish as you go to WOT? Try using a hotter spark plug are the plugs wet and black or dry and tan? When you change plugs try opening the gap up .003in. If you are using the same plugs as you did when you made all the engine changes and they fouled, it's better to replace them than having to deal with "maybe the plugs are OK". Going back to the basics is time consuming but usually results in a proper diagnosis. Start at the beginning and work forward. If you have good compression, good spark, and good fuel delivery, the only thing left is timing. Cam timing or ignition timing. Bill :)
 

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I am running golden lodge 2hl plugs, a bosch blue coil, a remapped distributor.
With points? If so, you may have marginal sparks. The Bosch blue coil works well with points but it does not make a high energy spark. My first GTV had a similar ignition and I was always struggling with flat spots in the 2000 to 3000 rpm range. I replaced it with a Marelliplex and it made a big difference. These days I use an MSD spark box and a Blaster coil with the plug gaps set at .045". I want the biggest spark that I can get with Webers.
 

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A couple other ideas FWIW:
- I found lodge 2hl's horrible at idle compared to NGK when I did a back to back test with the same setup otherwise on the motor. I would suggest you go to B(P)7ES or similar. Make your choice whether you want projected tip (the P) or not, and you may need to index them to keep the ground electrode away from your intake valve, at least from my experience. I personally am never going to touch lodges again.
- When my car was on webers (now spica) I had trouble regularly with the accelerator pump jets getting blocked or partially blocked off after having not run for a week or two, that would make starting very difficult until I pulled them out and cleaned them.

One way or another, starting from cold with webers, at least in my experience, was never a totally easy task... Part of it is some experimentation of how many throttle jabs to try before the first crank. Try increasing the number until the first crank catches properly, then vary a bit around that number depending on whether the ambient temp is cold or warm.

FWIW.
/Neil
 

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Part of it is some experimentation of how many throttle jabs to try before the first crank.
There is an old folklore formula for this. Take the current ambient temperature in degrees F and subtract it from 100. The result is the number of throttle pedal jabs needed before cranking. ;) :rolleyes:
Just kidding.

Hmm, sounds like too much choke to me.
I agree.
As an FYI, of all the Webered Alfas I've owned over the years, I've used the choke only once; and it promptly fouled the plugs! I simply do not use the choke at all.
As Neil said above, it takes a bit of experimentation to 'estimate' the number of pumps needed before a cold start crank. Variables include ambient temp, how long the car sat, fuel level (if any) in the carbs, etc. Of course without the choke, one needs to feather the throttle for a bit til the engine will idle on it's own. But this is just one of those little things that makes these fine machines so endearing, no?
 

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Discussion Starter #10
update:

I seem to have solved the problem, or at least significantly improved it! I was alway operating on the assumption that I had a carburation problem, but most of the advice I got from you was leaning toward an ignition problem. I ran through a couple of items and here is what i found:

Coil: switched from bosch blue coil to pertronix flamethrower- no difference
Checked timing and advance- both within spec
dissassembled intake and checked for float valve leak and blocked pump jets- no problem
Switch plugs from golden lodge 2hl to NGK bp7es- noted plug 3 was black and plug 4 brownish black
Measured resistance on HT leads- lead 3 and 4 measuring high!
Replaced all HT leads- Problem solved!!!

Car now starts with 1/2 choke and a couple of pedal pumps. Car also idles absolutely smoothly and runs better than it ever has!!!

Thanks to all of you for your input.
 

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My mechanic thinks the problem may be related to a starter jet that is too small. I can't find any information on the sizing of starter jets for these engines.
I just came across your post, and see that you have your problem solved.

As most replies indicated, most carburetor problems end up being ignition problems (and visa versa).

But, I have to ask: What the heck is a "starter jet"? Did your mechanic really say that?
 

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The starter jet, aka choke jet, is part of the cold enrichment system. It is a calibrated, and replaceable, component like any of the other jets in the carb. 40 DCOE Alfas up through type 80/81, as well as all the 45 DCOEs, were fitted with 65F5 starter jets.
 

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Here's the skinny! I've been driving my 79 Fetta all winter in Vermont. It's COLD not only Cold but " " COLD -15F. I've been using a $14 electric dip stick to solve all these problems. Like you I wake up in the morning and make your coffee and when I'm waiting to get that 1st cup I run outside with a piece of paper towel lift me hood and remove my Dip Stick and plug in me Electic Dip Stick from Amazon. After an hour I jump in me 79 Fetta with Spica no less and 20/50 OIL #### BAM it fires up, been running all winter. So you can can check all his stuff or spend 14 bucks on a Electric Dip Stick and plug in your Baby and all your worries will be gone!
 
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