Alfa Romeo Owners Club of Australia Forum

Technical => 105/115 Series (105 Coupe/Spider/Berlina) => Topic started by: f1fascination on September 11, 2013, 10:08:04 AM

Title: Fuel issues?
Post by: f1fascination on September 11, 2013, 10:08:04 AM
Hi again,as previously stated I've recently fitted a new (standard) head and rebuilt the carburettors on my GTV 2000 after it was found the head was knackered.
On reassembly,it took a long time to start, and when it finally did, it only runs on the rear carburettor it seems.
It sounds as if it's only running on 2-3 cylinders, and disconnecting both number one and number two plug leads individually makes no difference to the running. It idles, but only barely.
Does it sound like a float level issue, or have I missed something else? The carb's were rebuilt using the standard jetting as the new head was all standard, though new.
The plugs are firing on one and two, as I can hear the spark arcing when I disconnect the leads, and I have swapped the plugs around to the rear cylinders and they seem fine, and make a noticeable difference to the running when disconnecting, so to me it looks like a fuel issue with the front carb. The plugs on 1 and 2 are dry when pulled out.
Any thoughts?
Title: Re: Fuel issues?
Post by: Mick A on September 15, 2013, 12:35:47 AM
From what you've described yes a fuel issue perhaps.

Pull the tops off the carbs and check the float chambers for fuel and level.
Title: Re: Fuel issues?
Post by: Colin Byrne on September 18, 2013, 08:31:06 AM
Do the other two cylinders start to come in when you rev it?

Have you synchronized the two throttle plates?
Title: Re: Fuel issues?
Post by: f1fascination on September 18, 2013, 02:01:17 PM
Thanks guys, it sounds like the other two pots start to come in with some rev's on, but definitely not at idle, and I haven't checked the fuel bowls or the throttle plates yet.
Title: Re: Fuel issues?
Post by: Mick A on September 18, 2013, 02:12:32 PM
Well do that then mate.
Title: Re: Fuel issues?
Post by: Colin Byrne on September 18, 2013, 02:15:54 PM
Quoteit sounds like the other two pots start to come in with some rev's on

if that's the case then definitely look at the synchronization between  the two carbies
this can be done by removing the little brass plug on the top of the carbie that covers the idle bleed holes, if you shine a torch through the holes you can see the edge of the throttle plate, by lining up the throttle plates to the same hole on each of the carbies you can very accurately synchronize the two throttle plates with the screw adjuster between the two carbies

id also confirm that the idle screws are all the same amount of turns from their seat

Title: Re: Fuel issues?
Post by: f1fascination on September 18, 2013, 02:24:19 PM
Sounds great guys, this an excellent forum and I appreciate the great help you all provide, so many thanks!!!
I'll be sure to let you know how I go :)
Title: Re: Fuel issues?
Post by: f1fascination on September 25, 2013, 11:10:24 PM
Up and running and tuned well with a synchometer from Classic Alfa, thanks all :)
Title: Re: Fuel issues?
Post by: f1fascination on September 28, 2013, 11:04:59 PM
[i]if that's the case then definitely look at the synchronization between  the two carbies
this can be done by removing the little brass plug on the top of the carbie that covers the idle bleed holes, if you shine a torch through the holes you can see the edge of the throttle plate, by lining up the throttle plates to the same hole on each of the carbies you can very accurately synchronize the two throttle plates with the screw adjuster between the two carbies
[/i]


Which plug is this one guys?