Alfa Romeo Owners Club of Australia Forum

Technical => 105/115 Series (105 Coupe/Spider/Berlina) => Topic started by: lhodgo on February 25, 2018, 05:32:42 PM

Title: Twin Carb’s
Post by: lhodgo on February 25, 2018, 05:32:42 PM
Hi,

I'm putting together bits for my restoration and have two sets of twin carbies. I have the Weber's in the images and a pair of Solex. Wondering if I should pay a specialist to re-build the Weber's or sell both sets and get new Weber's? What would the relative value of these be and do you think someone would be willing to buy them? Wondering if I can sell two sets to get one better set?

Sorry I'm bit of a rookie with this stuff.
Title: Re: Twin Carb’s
Post by: Citroënbender on February 25, 2018, 05:36:59 PM
Wouldn't sell them just yet.

They've got patina and vintage up their sleeve, most defects are serviceable. You'd be surprised what a combination of ultrasonic cleaning and vapour blasting can do for old parts.
Title: Re: Twin Carb’s
Post by: lhodgo on February 25, 2018, 06:41:31 PM
I do have a ultrasonic cleaner but it's too small for these.
Title: Re: Twin Carb’s
Post by: Citroënbender on February 25, 2018, 06:53:00 PM
The worst things are usually rotary wire brushes, in fact probably the only brushes you might consider - if they're still sold - are the "Machinery Cleanery" brand ones made here. 

Vapour blasting is about, it's not so easy to find as dry blast though. 

General comment on restorations - it's a real art to balance consistency of appearance from one part to the next, from one end to the other.  You don't often see it; most restored cars have "feature parts" that are brighter or smoother than new, whether by design or happenstance. 
Title: Re: Twin Carb’s
Post by: Paul Gulliver on February 25, 2018, 09:41:35 PM
If your in Melbourne and want them restored try these guys.

http://www.thornburycarburettors.com.au/information.php?info_id=4
Title: Re: Twin Carb’s
Post by: LukeC on February 26, 2018, 08:16:43 AM
People ask wild amounts for Webers on Fleabay... But I would put a realistic value on those at $250 - $300. Then the professional overhaul is another $600 -$700 or so. If the car is standard-ish, I recommend using the originals. Performance: new Spanish Webers are about $1100.

Below are a couple a sets of carbs I used a bit of spit and polish on... Dellortos before and after.
Title: Re: Twin Carb’s
Post by: LukeC on February 26, 2018, 08:21:34 AM
Only kidding. The carbs in the first picture were history. I use fine glass bead in a cabinet. Of course, the carbs must be completely stripped and meticulously cleaned afterwards.

Title: Re: Twin Carb’s
Post by: aggie57 on February 26, 2018, 09:43:48 AM
Personally if I was in your shoes I'd first get the Weber's checked by someone like the firm Paul has referred you to.  I would consign the solex carbs to the nearest round filing cabinet.

Why?  Webers have changed over the years, yours are the correct DCOE32 model and appear period correct for a 105.  Even the ones fitted to Alfetta's were different to suit handle emissions requirements.  The new ones are much different again.
Title: Re: Twin Carb’s
Post by: lhodgo on February 26, 2018, 07:16:01 PM
Thanks all. Question, I get the bead or vapour blasting but how do you bring back the brass bits?
Title: Re: Twin Carb’s
Post by: lhodgo on February 26, 2018, 07:19:20 PM
These rebuild kits worth considering?
Title: Re: Twin Carb’s
Post by: bonno on February 26, 2018, 07:41:18 PM
Apart from an effective clean externally and internally of each carburettor, you will need as a minimum a rebuild kit for each. Additionally, there are several Youtube videos on servicing weber carburettors on the net and a search of this forum you will find one. Find attached link to the Weber carburettor site, for all your servicing needs.
https://www.weberperformance.com.au/index.php?cPath=5
Title: Re: Twin Carb’s
Post by: lhodgo on February 26, 2018, 08:37:41 PM
That's great. I think this is something I can have a go at myself. Thanks for all your help guys.
Title: Re: Twin Carb’s
Post by: Citroënbender on February 26, 2018, 08:43:29 PM
I believe it will help appreciably if you bone up on the Webers first, to understand the fuel/air circuits inside them. It will also help to understand the significance of any deterioration, damage or modifications spotted.

And, call me a cynic but I would secret mark (and photograph my marking) any carb handed over to a rebuilder or blaster.
Title: Re: Twin Carb’s
Post by: shane1750 on February 27, 2018, 07:39:55 AM
Hi
   Ditch the Solexs. Rebuild the Webers. There is a SpeedPro Series book HOW TO BUILD & POWER TUNE
WEBER & DELLORTO CARBURETTORS that is worth getting a hold of.
Title: Re: Twin Carb’s
Post by: carlo rossi on March 01, 2018, 02:37:06 PM
they arent bad stick with webers
they say they have a 100 year life expectency if looked after
yours might need bearings
but better than injection
they only last as long as the updates
Title: Re: Twin Carb’s
Post by: lhodgo on March 06, 2018, 09:00:26 PM
Any preference on fibre over paper gaskets and plastic over copper filters? I have both as a backup, wondering which to fit straight up? Thanks.
Title: Re: Twin Carb’s
Post by: carlo rossi on March 07, 2018, 11:20:53 AM
all good I prefer fibre and copper
old school
Title: Re: Twin Carb’s
Post by: lhodgo on March 07, 2018, 04:43:48 PM
Well I've got both, might go old school and keep the others as spares!
Title: Re: Twin Carb’s
Post by: lhodgo on March 12, 2018, 07:39:08 PM
So I've got some aluminium mounts to upgrade from the original rubber ones and some 50mm extensions to increase the inlet and get some better performance (I hope). Question is, where does the rubber o ring seal? Against the carb (top one in image) against the extension (bottom one in image) or should I flip the entire layout and have the mount and o ring against the manifold?

Thanks
Title: Re: Twin Carb’s
Post by: carlo rossi on March 13, 2018, 01:55:22 PM
between the carb and the ext tube is where the o ring goes
Title: Re: Twin Carb’s
Post by: lhodgo on March 14, 2018, 09:19:30 PM
Hang on the top outlet or the bottom outlet in my photo? See how I've got two options in the image?
Title: Re: Twin Carb’s
Post by: carlo rossi on March 16, 2018, 03:59:08 PM
generally its right between the carby and the manifold or the adapter
thats if i understand the question
Title: Re: Twin Carb’s
Post by: lhodgo on March 16, 2018, 08:37:33 PM
My carbi mounts have a rubber 'o' ring on ONE side only. I'm trying to work out if the rubber 'o' ring pushes up against the carbi or against the 50mm extensions I've also added. Or are you saying I should have the 50mm extensions against the carbi, then the 'o' ring side of the aluminium mount facing the manifold?

If you look at the photo,  the top outlet has the o ring facing the carbi with the lower outlet facing the 50mm extensions.

Trying to work out which is the correct option in that photo.

Thanks.
Title: Re: Twin Carb’s
Post by: lhodgo on March 16, 2018, 08:42:00 PM
I've circled the o rings in red
Title: Re: Twin Carb’s
Post by: LaStregaNera on March 21, 2018, 09:34:42 AM
Standard practice is to have the o-ring against the carb.
Title: Re: Twin Carb’s
Post by: Craig_m67 on March 21, 2018, 02:02:32 PM
There's a lot of discussion on the AlfaBB (US) about the correct way to install aluminium carb mounts (vs rubber), and any issues that people then solved etc..

I've not installed them on either of my 105 Nords so have no experience to offer.

I only chime in as I remember it being very topical at one stage and I was considering it - in the end i did nothing, just drive  :)
(perhaps when the original [Pirelli?] rubber mounts were unobtanium)
Title: Re: Twin Carb’s
Post by: bonno on March 21, 2018, 04:06:52 PM
Straight from the horses mouth regarding o-ring position relative to carby and manifold (eliminate vibration between engine and carburettor/s). Find attached link to the weber website on soft mount kit.
https://www.weberperformance.com.au/index.php?cPath=115_101
Title: Re: Twin Carb’s
Post by: carlo rossi on March 22, 2018, 02:01:25 PM
the top circle
immediatley after the carby either will do
but both the same is ideal
Title: Re: Twin Carb’s
Post by: lhodgo on March 24, 2018, 12:56:50 PM
Awesome guys, thanks heaps!!!