D'ellorto rebuild who is the best?

[jeff jackson]

Hi all,
The time has come to bite the bullet and look to have my Dellortos properly sorted.
For years I have set the float levels, put new gaskets on, new O rings, tightened the Thackary washers up using feeler gauges, bought a manometer to balance them and bought the Hammil book on servicing Dellortos. I have finally decided that it's probably air leaks from the spindles, or the accelerator pump, worn jets or some other gremlin that makes my car run lumpy, rich, fast, slow, stall, one day quick or one day sluggish.
I have looked at the eurocarb site, searched the archives and looked at the vendors suggested for Weber rebuilds, but I wondered if anyone can recommend a rebuilder of Dellortos aside from eurocarb in the UK?
has anyone had their carbs rebuilt by Eurocarb? Good? Bad? indifferent?
Also spoke to a chap at Beaulieu on Saturday, http://www.bustedknuckleracing.co.uk/ Has anyone experience of them?

Sorry for the questions, but it looks like I would be parting with quite a bit of cash, so want to spend it wisely.
Kind regards
Jeff 72+2

[trw99]

Jeff, have you looked at the Espirit,and Excel forums? Their carbs are Dell'Ortos so they should know good shops.

Tim

[jeff jackson]

Hi all,
Searching the forums I have contacted someone who can help.
However, they did ask for information on what jets were fitted to my D'ellorto's.
Here is what is in the workshop manual.
Type D?ellorto DHLA-40
Part number identification
Front Q026 S0710W
Rear Q026 S o711W
Colour Code Red
Settings:
Choke 33mm
Auxiliary Venturi 7848-1
Main Jet 120
Main air corrector 130
Idling Jet 50.02
Idling Jet holder 7850-2(120)
Pump Jet 45* (* use 35 if necessary to improve driving)
Starter Jet 70
Main Emulsion tube 7772-5
Starter Emulsion tube 7482-1.28
Needle valve 150.33
Float Assembly 7298-01
Air Trumpet length 40mm

The reply came back like this:
142 mains
180 air correctors
55 idles, everything else is OK.

120 mains to 130 airs is not good.
So why would they be suggesting something wildly different to the standard?
The Des Hammill book suggests a main jet as a 130 for 350c.c. per cylinder and 135 for 400cc per cylinder. somewhere in the middle is just about 1558cc.
has the spec changed because of leaded petrol? Or is this bum information?
If anyone has had their carbs refurbished and the jets changed I would be interested to find out what you had done and why.
Kind regards
Confused in Dorset. (72+2)

[trw99]

Not sure this helps much, from my Sprint site and a distillation of various official sources, indicating some discrepancies, as well as the European specs:

Dellorto Carburettor DHLA 40
Choke 33mm
Main jet 120 (135 European emission)
Main air corrector 130 (200 European emission)
Accelerator pump jet 35
Idling jet 50.02 (47L European emission)
Starter jet 70
Needle valve 150.33
Air trumpet length 42mm
Front ? part number Q026 S 0710W
Rear ? part number Q026 S 0711W

Tim

[jeff jackson]

Thanks Tim.
Confirms what I have in the book.
Bit concerned about sending the carb off now.
Kind regards
Jeff

[elansprint71]

Just had mine done by this man: http://www.weber-carbs.co.uk/
Can't believe they are the same units! I asked Paul to fit the jets specified in the Lotus Manual: that's a good starting point. I'll be heading for the rolling road at some time in the future.

[Chancer]

He might be right on the money, often a change of main and air corrector if done in the correct ratio, and his do seem to be correct can transform the idle to progression or progression to main jet transition without changing the mixture.

I would not question or judge his competence by his jetting recommendations unless it was something I knew very well like tuned Xflows on webers.

The jetting he decribes might cure your problems without the need of a rebuild, in which case he is being very open with his knowledge and should be commended, its not a lot of money to give that configuration a try and you can never have too many spare jets.

Given how much they cost me in the day I thought my collection would be my pension fund but thanks to the net they are far cheaper now than in the 80's.

[jeff jackson]

thanks for your thoughts.
What I have decided to do is go with the originals for the rebuild, and then get it on a rolling road.
That way we can play with the recommended jets and see what works.
It can't be any worse than the way they are at the moment!
Kind regards
Jeff

[mark030358]

Pete,
Was the finish a bead blast, or some other coating.
Can he/Did he balance the barrel to barrel flows?

Thanks
Mark

[elansprint71]

Mark
I think he cleaned using untra-sonics but I'm not sure. Don't know about the flows; why not ask him, he's a nice chap.

I'm struggling to balance the carbs, see separate thread.

[persiflage]

Having sat for a long time without running, it was time to give it a try. Aware of potential issues with the state of whatever fuel remained in the tank and pipework I fabricated a small auxiliary fresh, clean fuel supply but the car refused to start, it quickly became clear that it was a carburettor issue. These carbs are not the original from 1972 but new ones supplied by Eurocarb during rebuild, (many years ago) .... no more than a couple of thousand miles on them.
Float chamber covers removed, and what had left the rear of the car as clean fresh fuel was found to be a very dark treacle colour.

Flushing the pipework with fresh fuel took 3 large jam jars before it ran clear.
I took the offending items along to Paul at http://www.weber-carbs.co.uk

About ten days later I picked up the reconditioned units, that looked better than new.

When fitted, the car fired up with very little effort, and smiles all around.
After a short while it became evident that there was a very small weep from the area of the accelerator pump on the forward carb that manifested its self as a drip on on of the housing screws.

Without hesitation, Paul requested that I return the carbs for his inspection, offering to cover the cost of courier in both directions. On close inspection it was found that about one third of the length of the pump casting had been poorly machined at manufacture, leaving a rough uneven surface.

The rough area was polished smooth and the carbs now refitted and running are bone dry.
Paul was a pleasure to do business with, prompt with any communication and very reasonably priced and I would not hesitate to send work to him again.