Weber Carby Genius wanted!

[DaveSpec]

Hi,
I am after either a weber carby tuner on the sunny coast or brisbane area and an approx price of how much it would cost to get the carbies tuned, orr
someone awesome on toymods that could answer a few questions i had about the carbs.
Either would be excellent and thanks in advance

[ToyTA22]

Easiest way is to post the required info and what model of carbs you are using. Also as much detail of engine specs if you require jetting info.
I have dealt with Dcoe's and Dgv models

[DaveSpec]

Alright so its an 18rg 2252 head
with stock 18rc pistons so a 8.5:1 compression ratio i believe.
no pollution or smog hardware.
extractors and 2.5inch custom exhaust
twin 45mm webers with redline manifold

webers are:
DCOE
1 is a DCOE 39 and the other is a 152
both have 3 progression holes on either side
130 main jet
f15 emulsion tube
45f9 idle jet
175 air correctors
50 pump jets
Not sure what size chokes they are because i can't see a number stamped out them anywhere, thought you were supposed to be able to though.
Not sure what size aux chokes either because i belive i have tot ake them out to find out.
There is however a 1 stamped on 1 of the chokes and a 2 on the other for each carb.
These carbies have been rebuilt (not by me) and never run on an 18rg. where about to be set up i think be the ex owner blew 2 pistons

Have attempted balancing with an analog airmeter and obtained a nice smooth idle around 1100rpm, took her for a drive and it misfired an little bit then after about 5mins it got to the point that i couldn;t rev the engine and had to limp back. Took the plugs out and the front two were a tan and the black 2 for a dry black soot (guessing too rich).
Not sure if this would be caused by incorrect balancing of the mixture screw or even the jets?
Getting really stuck with this car because i just want to get her on the road for the moment. Would be happy going back to the original carbies if i had them because i'll just end up fuel injecting this engine i think.

Any help would be greatly appreciated!!

[Dazza]

If you couldnt rev the engine then your plug colour would be showing what your idle mixtures are. i checked my Haynes Weber carby manual and it only shows jetting for an 18RC with twin 45mm DCOE webers. It says to run 140 main jets and the rest of your jets and emulsion tubes will be ok for an 18RC with 40mm carbs. I would think that by running 45mm carbs and an 18RG head you would need bigger main jets that are around 145 or 150

[ToyTA22]

I agree with Dazza, about main jets too small and his sizes would be a good start.
Have you checked float levels, if two plugs are tan and other two black which sounds too rich check float levels and also jets possibly aren't seated correctly. This applies to idle and main jets. People have bad habit of pushing jet right into holders on dcoe's. When reinstalling jet holder push jet just short of being right into holder, about 1mm, then install and screw in holder until firm to tight, warning do not overtighten can easily strip alloy bodies.

[DaveSpec]

So im guessing the jets are wrong, but the front and rear carb have the same set up. Except the chokes could be different but i doubt it.
Have been able to get the car running well by allowing air to enter the manifold after the each throat of the rear carb.
So theres definitely too much fuel in the mixture, its weird that i only need to do this for the rear carb and not both.
Could this be caused by incorrect float or do i just need different jets because its a different model carby?

[ToyTA22]

I still think it's the float setting. Can you read the model numbers on top of both carbies just in front of round jet cover? If so could you post them up.

[Dazza]

The needle and seat on the rear carby could be leaking causing it to run rich if the float level is correct. Sometimes needles with a viton tip can stick to the seat if they havent been used for a while and will rip a small piece out when pressurised fuel forces them apart. If a small piece is torn out the needle will leak and make your carby run rich.
Also check that the throttle butterflys are opening the same amount on both carbies. You can use a thin piece of wire or a small drill bit to check how far they are open in the idle position. When the butterflys are syncronised you can then sycronise the idle mixture screws.

[DaveSpec]

I still think it's the float setting. Can you read the model numbers on top of both carbies just in front of round jet cover? If so could you post them up.

Yeah one is a DCOE 152 and the other is a 39 (this is the one running rich)

The needles don't look like theres anything wrong with them. I will check the float levels tomorrow. Is there any way to check if the needles seat properly? can i take the cover of and shoot compressed air down them and see if they're leaking? i can't remember if you can see the needle seats with the top off.

[Rodger]

One way to check float level or a leaking needle/seat if you have an electric fuel pump, is to run the pump until you either have fuel running out the carb or the pump loads up against the needle. Remove the tops and see if the fuel is at the same level.

I also second the way the fuel jets are installed onto their emulsion tubes. Lightly push in a very small way. The fuel jet is tapered to seat at the bottom of the housing and is pushed there when tigtening in the emulsion tube. If it does not seat it allows fuel around the metering hole to make a rich mixture.

Regards

Rodger

[ToyTA22]

Rodger just reminded me, are you using standard or electric fuel pump. If using electric, without reg, check fuel pressure. Webers are designed to run maximum 4 psi pressure.

[DaveSpec]

Yeah i am running an electric pump and i realised this yesterday so i check the PSI it was around 7 so i got a regulator and its dropped to about 3-3.5PSI. The float on the rear carb was out quite a bit so i re adjusted that, and re sat all the needles. seems to be running much better now, well i can disconnect the air entering the intake manifold and shes idles. Going to try tuning the carbies. Whats the best way to synchronise them? have tried a hospital like meter (the one with the ball) but it isnt quite sensitive enough to get an accurate reading

[DaveSpec]

So i think i might be in need of othersized jets. Does anyone know where to get jet pacs in aus for a good price? or have any laying around their shed they're willing to part with?

[roadkill]

Hi,

first thing - get two carbs that are the same. I'd think that pissing about with two different carbs will never work in your favour.

Second - Contact Norm Singleton - he is a fiat nut and hence knows webers bloody well. Website - http://www.fiatabarthclassicracing.com.au/ he's near samford. He did the 45mm webers on my 18rg so he's familiar with the engine too. Did an unreal job too He'd be nearing 70 now and knows his stuff!

bEn

[DaveSpec]

Thank you very much. I've been looking for someone to tune the webers because it wouldn't make sense to buy a while bunch of jets and check each one to see if its best. I'd much rather someone who knows what they're doing take a look