DCOE Issues (Yet again)

[Nathan]

Only a simple one well kinda simple to those who know i hope.


right the carb has been running sweet and car was workin like a dream THEN!!!!!!!

she started to die when idle and cough a splut on the rev up, i did the usual check the plugs looked kinda wet which i thought humm CARB again, just to make sur ei checked the dizzy then i remembers i got magnatronic.

As time has gone on to stop her dyin when idle i have just adjusted the tick over, and se seems file however now i reckon cus the carb is commin out of tune she is venting alot of fuel through the exhaust which is good in some respects as it makes a nice popping noise however i have had this before with SU's and it only ebds up in a blown back box.

I was wondering if anyone knew how to give the carb a quick adjust, SU's are much simpler well i reckon so but this thing i don't dare touch well not yet as it new, i reckon from the symptions too much fuel is being let into the chamber and not being burnt off. I only want this a quick fix as at the end of the month its being rejetted for a RACE head


Cheers Nathan

[iRocco]

It sounds like the idle jets need adjusting.

If I remember correctly it's the two screws at the top of the carb closest to the manifold. You need to adjust these together (one per jet). Again, if I remember correctly adjust them 1/4 of a turn at a time clockwise - you'll soon know if you're turning it the right way. You should only atempt this when the car is running at normal temperature on idle.

Are you running a choke on it?

[Nathan]

Nope no choke on it, well the carb has the choke but no cable attached she seems to run ok without even in this weather.

I remember the screws, could be a possibility that the vibration has knocked the adjustment out,

[iRocco]

The shouldn't vibrate out of tune TBH as they are adjusters on springs - have you got the rubber 'O' ring gaskets between the carb and manifold?

There is a chance that the needles / jets have become warn - but this is a slim possibility. Was the carb new or 2nd hand?

Take the access plate off the top of the carb and check that nothing has got in there that shouldn't have..........

[BenzBoy]

It could be that the idle jets are too big. The air correction screws should get it to run OK but if there's too much fuel going in there, it's always gonna have a fast idle - but at least it'll not keep dying on you.

I'm having fun and games with a pair of twin 40s at the minute... you're right, SU's are loads easier to work on!

[iRocco]

.......but don't sound as good......!

[Nathan]

Yep the carb is new bought it from EuroCarb who are in Retro Cars,

Yep got the rubber O rings in place, this is the second time its done it and i sent it in to have a look at my local tuners who were the poeple who set her up in the first place. just gets on your nerves sending it in and paying for 2 screws to be adjusted. i will try that tonight guys cheers


P.S. also Rejetting the webber does this require new components inside like the SU as i am about to get the new head i want to get all the part required before i send it in again

[iRocco]

Yes, re-jetting requires new jets.........! Although if you're just putting a different head on, it will probably only require new needles not jets.

EuroCarb - just down the road from my parents.

[Nathan]

cool cheers mate,

Yer they are actually quite good got for a bargin so cant complain MG wand 690 for the carb and the inlet.

Also for a race head they want 900 notes no way only 500 from HeadWorx and they don't charge 150 for exchange you get to keep your old one

[BenzBoy]

iRocco said:

it will probably only require new needles not jets.

I didn't think Webers had needles . The SU's do because they're variable venturi, and use the needle to increase / decrease jet size (as you probably know!)
Webers have a multiple jet set-up and fuel flow is metred by the emulsion tubes etc., etc.
A new set of jets will be in the region of £70 I think.... We got ours from a Carb place near the Cattle Market in Nottingham (can't remember what they're called! I'll try and remember ) - not far to travel .

Psychodriver gave me a link to a jetting calculator for DCOEs and DellOrtos, but I think it assumes you're running a pair of 40s - I'd assume you're running 1 on the B... unless you got an 8 port head on it! ;D

[BenzBoy]

Here's that jetting calculator -

hometown.aol.com/dvandrews/JETTING.EXE

Like I say, I think it's for twin 40's and 45's but I ain't 100% sure. Let me know if you want to know where that carb place is in Nottingham, and I'll dig out the address and stuff!

[Nathan]

Cheers mate, Yer that place would be great if you can find the addy for me

Na only running one had an offer of a custom inlet but just was not worth the money really not on my little engine

Many thanks

Nathan

[iRocco]

BenzBoy said:

I didn't think Webers had needles . The SU's do because they're variable venturi, and use the needle to increase / decrease jet size (as you probably know!)
Webers have a multiple jet set-up and fuel flow is metred by the emulsion tubes etc., etc.
A new set of jets will be in the region of £70 I think.... We got ours from a Carb place near the Cattle Market in Nottingham (can't remember what they're called! I'll try and remember ) - not far to travel .

Psychodriver gave me a link to a jetting calculator for DCOEs and DellOrtos, but I think it assumes you're running a pair of 40s - I'd assume you're running 1 on the B... unless you got an 8 port head on it! ;D

Yes, you are completely right. What I meant to say was that you'll probably only need some jets replacing not all of them.
The new jets for my 45DCOE came to about £60 - that was for 2 idle jets and a new pump jet (mine was warn apparently). It cost me a total of £130 for a complete RR session and the new jets.

[Nathan]

thats not bad hopefully it will only cost the £60 and the usual fitting, i am going to have a play with the carb tonight just to see if i can get her to run a bit better, the whole street is getting kind of anoyed, but my argue is it sounds so good, popping is a bit loud though

[iRocco]

As long as you do it after 9am and before 11pm they can't say anything......

[Nathan]

true very true

the guy is a retro hater though so what can you do, ahh well thanks for the aid guys should be sorted today now

[iRocco]

Pour lemonade over his car when it's frosty, or fill a cup full of brake fluid and turn it upside down (with the aid of a beer mat) on top of his roof.........

[nickb]

iRocco said:

Pour lemonade over his car when it's frosty, or fill a cup full of brake fluid and turn it upside down (with the aid of a beer mat) on top of his roof.........

NASTY!

Brown sauce will have a similar effect to brake fluid on the paint. And probably will be less likely to lead to you being done for GBH....

[Nathan]

lol now they sound good, ah well he will have to lump it

[iRocco]

Yeah, but brake fluid affects the metal as well, so you'll need a lot more than a respray to fix it

Four small pieces of wood with nails in them placed behind the front wheels and in front of the back wheels is a good one as well.........