Carb refurb

[Molecular--Bob]

I think i need to get my carbs refurbed, one of them looks to be full of bits, and that can't be good. They also seem to leak from the bottom plate seals despite re-fastening these, so time to get them done. The car had stood for a while before i got hold of it and the carbs are covered in fuel residue which may have blocked some of the jets. So all in all they look a bit sorry for themselves.

 

Who have people used? and what sort of turnaround time could i expect?

[Nigel Riches]

Bob, I've used these people here for supply of parts.

 

They were prompt, and as Norman Verona says he used to use their services when 'e were a lad int' mootur trade, so they probably know what they're doing by now.

 

However the prices were a bit eye watering, might be a starting point.

 

Regards Nigel.

 

1982. 5 speed, clamshells. B.R.G / Ali. The True Colours.

[Neil MH]

You could also try Southern Carburettors in Wimbledon. 0208 540 2723.

 

I used them many times for parts and advice. I am sure they do the refurbs as well.

 

I have always found them very helpful.

 

 

Neil

[Mcalvert]

Big for Southern Carbs - they definitely will do the refurb for you, or just sell the refurb kits if you want to do it yourself..

 

Michael.

[Sheds Moderator]

Bob, carb refurbs are easy enough if you can get hold of comp air (even a computer cleaner aerosol) to blow out the jets. The rest is just kitchen table mechanicals.

[Super_Rich_Bernie]

I have two DCOE webers sitting on my workbench waiting to go onto my Alfa. I spoke to Southern Carbs who quoted (from memory) £150 per carb. However they had a bit of a backlog, and wanted 6 weeks to do them. Gower & Lee quote slightly less money. Since I live in Wimbledon avoiding carriage costs would have balanced it out.

 

In the end I decided to go the DIY route. The carbs are in bits, cleaned up, and waiting to go back together. I found it quite rewarding, and assuming they work when they are bolted to the car it will have been a satisfying thing to do. (Maybe I'm just odd like that!). I also now understand how they work.

 

I soaked all the removed bits in cellulose thinners to clean them, and bought a rebuild kit (about £20) with the gaskets etc. I have some cutaway drawings so I can see how they go back together. I can only work on them when my wife is out since its a kitchen table job to keep it all clean.

 

Jonathan

 

[Sheds Moderator]

I can only work on them when my wife is out since its a kitchen table job to keep it all clean.

I bet she loves you!

"Oh, hello love, swimming finish early did it? Er, just let me clear away this stuff, er would you like a cup of tea? No, there are no cups in the dishwasher, no, you don't need to check, no DON'T GO IN THERE! 😳 😬"

[McBreadhead]

😬

[Molecular--Bob]

Thanks all, i had forgoten about this thread.

 

I think i will give the DIY refurb a go. What is the best solvent to use to clean out the carbs? I have access to ultrasonic cleaning tanks, airlines and chemical fume cupboards so should be able to use pretty much anything.

 

Do the refurb kits from weber contain new needle valves?

[Normans_Ghost]

MB, we used to use the dry cleaning fluid (can't remember the name). Banned because it was just to good for cleaning, sniffing was great though.

 

Trico? is that it? Tricoethylene?

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

You and your seven to The French Blatting Company Limited

[peterg]

Yeah, that's the stuff Norm, banned 'cos it was found to be carcinogenic

 

Either Carb Cleaner or Brake Cleaner from Halfrauds or any motor factors will do a pretty good job now

[Molecular--Bob]

Trichloroethane? If it is that then that is one of the few solvents i can't get hold of, you need a licence to vent it to air before they will supply it. I might try xylene and methanol, it seems to dissolve everything including the nitrile gloves we use.

[Neil MH]

The refurb kits I got from Southern Carbs did contain needle valves. That was about 2 years ago though.

 

Neil

[JampJ]

Carefull when ordering the refurb kits, make sure you state that they are DCOE 40 151s ( If that's what they are), the idle mixture screws, (two per kit) are different on the earlier DCOEs. The early ones have a short taper, and the 151s have a long taper. Not interchageable.

The DCOE 40 151 is stamped on the top plate.

If you look at Ebay no 130028563642, you'll see that kit is for the earlier carbs, the later kit for the 151s is the same part number, but ends in 1 instead of 0, and are considerably dearer. I think he's selling at that price, because most cars now have the later carbs, and he's having trouble getting rid of the old kits. The screws are about £4 each.

Some suppliers are selling kits that don't contain the idle screws, but still charging silly prices.

Cheers J&J

 

JFDI

(Just F*****g Do It)

[Molecular--Bob]

Thanks for the advice on the kits, mine are 151 spec.

 

Are there any parts in the carb. that shouldn't be dunked in a strong solvent? or at least left in it for 24 hrs. I am thinking about soaking them for a long time, giving them a scrub, resoaking in fresh solvent and then giving them about 20 mins in a sonicating bath.

[JampJ]

There are a couple of rubber O rings, but you get them in the kit anyway. Don't know what condition the inspection cover and screws are in regarding plating, but some solvents may remove it, leaving the items prone to rusting afterwards. Some acidic cleaners will turn the alloy black, and remove plating. I use petrol, white spirits, or cellulose thinners and an old hard toothbrush, seems to do the trick.

Cheers J&J

 

JFDI

(Just F*****g Do It)

 

Edited by - johnjulie on 12 Oct 2006 08:48:39

[Nigel Riches]

Go careful with any acidic cleaners as the diecast zinc wont take kindly that sort of treatment, certainly not immersed for 24hrs, don't feel that there would be any benefit in doing that, once any contamination is dissolved it's dissolved, pull the bodies out and wash with water to remove any residual cleaner.

 

 

Ultrasonic cleaning tank would give the best results, and save time poking about into the dark nooks and crannies.

 

As recommended above carb cleaner is what you need, gets rid of the dirt and varnish build up, carbs will look like new after this treatment.

 

1982. 5 speed, clamshells. B.R.G / Ali. The True Colours.

 

Edited by - nigelriches on 13 Oct 2006 06:33:25

[Martyn Heesom]

The carb cleaner that comes in aerosol cans is mainly xylene.

[Sheds Moderator]

And cellulose thinners is mainly toluene, IIRC. This or xylene will be very effective. If you need something more polar, well, you're a (bio)chemist Bob, you can work all that out for yourself!

[Molecular--Bob]

I'm going with the xylene option in a tank on a rocking plate to give gentle agitation, followed by fresh solvent and a few minutes of sonication. Then repeat sonication in water to remove the solvent residue.

 

Are there any good books to guide me through the strip down and re-assembly?

[Manxseven]

Loads here

here

on ebay

 

 

Caterham Fireblade here

[Normans_Ghost]

40 years ago no one told us how dangerous Trico was. We used to book out 1/4 gill for cleaning carbs and it was great. Always worked over it and got light headed and started halucinating.

 

Do you thing it's had a long term effect?

 

 

 

 

 

 

jjdjaamwsknijas, jdkailkIKS, HOLSHJA, lllldjdghsyyavbga!

 

blobbbblobbshlobbbflooberkoobadobba

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

You and your seven to The French Blatting Company Limited

[Martyn Heesom]

Josh Bowler has a manual you can download as a pdf which would get you started.

 

http://www.bowler.fslife.co.uk/tuning_manuals_and_other_reading.htm

 

This is also available for download from

 

http://www.se7enup.hopto.org/se7enup/default.asp?id=0&ACT=19

 

 

 

 

[Super_Rich_Bernie]

Thought I would add my thoughts having finished the 40DCOE webers I overhauled - now fitted to the car.

 

I rebuilt a spare pair of carbs, of original spec for my 1968 Alfa, to replace the ones fitted which were non-original emissions carbs. The car went OK on those carbs, but they had been on it 20 years, and 90,000 miles. The ones I rebuilt would be late 60s, so were covered in grime, but otherise servicable. There was nothing actually wrong with the ones that came off.

 

Stripping them down was reasonably easy, but on one of them the auxiliary choke was well and truly stuck - some corrosion around the lip where the choke fits into the body. Without the proper weber choke puller I soaked penetrating oil in, then used a wooden drift, inserted past the throttle butterfly to knock the choke out. Once the auxiliary chokes were out the chokes themselves slid out easily. Everything else just unbolted. I left the throttle shaft and butterflies in place, since all seemd ok with them, and removing it looked difficult. One of the Accelerator Pump weights would not come out, even with vigorous shaking - so I had to file down a pair of tweezers. (wonder whether my wife will notice the loss of tweezers or the loss of a suede brush firts?)

 

Cleaning them took time. I don't have access to any clever cleaning tanks or fluid. Small pieces were left in a jar of cellulose thinners to soak and the body itself was cleaned with cellulose thinners and a suede brush with soft bristles. Intricate bits with a toothbrush (Several in fact, because cellulose thinners melts them!). There was some corrosion on the auxiliary chokes, which came off with fine wire wool. After cleaning everything came out clean, but they don't look 'as new' - which the ones Southern Carbs rebuild do. Not sure what they use to give the ali bodies the new look.

 

Putting them back together was easy enough with a cutaway drawing for guidance. The instructions in the rebuild kits are as good as useless, being a poor translation from Italian. The floats in mine did not need re-setting, and I can't see how they can change over time, so if they are right to start with, they should stay that way.

 

I replaced a couple of screws and springs which were not in the overhaul kit - available off the shelf at southern carbs.

 

A few things I learned....

 

The rebuild kit came with some fragile looking plastic fuel filters. I washed the original brass ones out and reused them instead.

 

There are lots of detail differences between 40DCOEs. Apart from the emissions units, which have different circuitry, the ones supplied to Alfa use the airbox to lock the auxilaiary chokes in place, and not grub screws underneath. If buying secondhand beware, because these carbs would not have worked with trumpets & K&N filters without surgery. Quite a few of the ones on ebay come from Alfas, since they were original fitment on most of their cars, and there are plenty about. The emissions units look the same too, so make sure you know excatly what you are buying.

 

These carbs did not have the idle bypass screws which the ones on my old Caterham had, and the emissions ones had. Not sure thats a problem either way.

 

Unlike my previous Caterham, which needed its carbs rebalancing every so often, the ones on Alfas hardly need touching. I put this down to them being mounted on flexible rubbers, having a solid airbox bolted on, and a strong steel support from the block to airbox. I guess they don't vibrate around as much, and therefore stay in tune better. Given that the carbs are servicable after so long, and stay in tune, any reputation webers have for being temperamnetal is more down to the way they are installed, than any inherent weakness in their design or function.

 

So a successful exercise, and the car runs noticably better now with the correct spec of carbs. The DIY option is a lot cheaper than having them refurbished by a specialist.

 

Jonathan

[Crudders]

If I can be a solvent geek for a moment (I used to work with chemicals in my summer hols years back so have probably suffered the same brain damage as Norm ) . . .

 

'Trike' was the name given to 1,1,1 Trichloroethane if I recall - most commonly used as an industrial degreaser. The pongy stuff used by Dry Cleaners is Perchloroethylene, aka Ethylene Tetrachloride.

 

Anyway, it's safe to assume that any chlorinated hydrocarbon based solvent is nasty - it enters the bloodstream very easily via inhalation or skin contact and once it finds its way to your organs, it stays there.

 

Cellulose thinner is from the Ketone group if I recall, not as nasty but still capable of detrimental effects to yer innards.

 

If you think the safety warnings on these substances are a bit 'nanny state' I strongly recommend a google - very scary.

 

I restored my carbs with this stuff from Toolstation here (second product down). It claims to be environmentally friendly and doesn't cost a lot. Spend another £38.00 odd (easily done ) and they'll deliver it FOC.

 

Funny the things you remember. I'm no chemist though, and I'm sure there must be some amongst us who can give a more informed view.

 

Crudders