Page 1 of 2
Weber 45 DCOE - Uneven fueling
Posted: Tue Aug 28, 2012 9:54 pm
by tomkidd
So, after trying to road test the mini it is proving an utter ball ache to drive. It runs rough and at some points lets out almighty back fires.
We whipped the plugs out and 3/4 are running very rich and 1/2 are running ok.
Does anyone know of any reason my weber would be doing that? Its just been jetted etc by a man who knows what he is doing so I think there may be a problem with the carb somehow.
Is there anything I can do to clean it all out?
I'm getting fed up of this bloody car
Re: Weber 45 DCOE - Uneven fueling
Posted: Tue Aug 28, 2012 11:10 pm
by rolesyboy
Tom, sorry but I know sweet FA about Webers. What I do know is that when you get that car running right and if it looks as well built as it appears then you will love it. I had a hat-full of teething problems with mine and to makes you feel better I will quote some examples. I returned from the Rolling Road having sorted the lumpy running as you describe to have the primary gear seize so I couldn't get out of third gear and had to be towed home (first time in 20 years!), followed by a failed 'new' solenoid, closely followed by a failed 'new' coil, followed by a seemingly incurable oil leak from the 'new' timing cover oil seal which after 5 x engines out and countless attempts to square the seal turned out to be a badly manaufactured cover.
After those issues the car has performed faultelssly on many occassions and always brings a smile to my face. Stick with it matey. Mark
Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 1:08 am
by Richspec
yes you can undo various bits to check yourself. You've already identified that one side of the carb is ok, so for now just check out the t'other.
From memory - undue the round cover on top? and the jets/emulsion tubes etc just unscrew out, its obvious but make sure they're all together tightly, and give them a clean / blow through, it could be you've got a bit of shite in there. Also note down the numbers stamped on the bits. **this is important**
Check for any loose nuts and bolts holding the ram pipes in place etc, check the security of the screws on the underside that hold each 'barrel' in place in the carb.
Compare the two idle adjusters near the front - are they the same?
Once your happy that theres nowt obvious amiss whip out the jets/emulsion tubes on the good side and check that the numbers match the others.
You'd think that after paying someone to set it up they would be the same. You'd be surprised
You'll soon get an understanding of the workings and its really easy to swap bits out for a bit of self tuning which is very possible using a lambda, a screwdriver and a motorway services on the way to mitp!!

Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 1:20 am
by Richspec
Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 6:01 am
by Astro
Hi,
as important as the Weber is the inlet. How does it look like? The first one I ever tried allowed only 7000rpm. What is about the filter? Is it just over the hot outlet and swallowing the hot air or did you cover your exhaust manifold? These points are as important as a well prepared Weber. Annother point is a compatible ignition and don’t forget the fuel pressure. This all differs from a SU.

Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 6:52 am
by 251 ENG
Webers can be a total pain to clean out correctly . There are lots of small drilled holes in the body that can become blocked over time . Sometimes the only way to clean them out is to take out the lead seals and drill them out .
A good rolling road man should be able to sort you out
Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 7:39 am
by tomkidd
rolesyboy wrote:Tom, sorry but I know sweet FA about Webers. What I do know is that when you get that car running right and if it looks as well built as it appears then you will love it. I had a hat-full of teething problems with mine and to makes you feel better I will quote some examples. I returned from the Rolling Road having sorted the lumpy running as you describe to have the primary gear seize so I couldn't get out of third gear and had to be towed home (first time in 20 years!), followed by a failed 'new' solenoid, closely followed by a failed 'new' coil, followed by a seemingly incurable oil leak from the 'new' timing cover oil seal which after 5 x engines out and countless attempts to square the seal turned out to be a badly manaufactured cover.
After those issues the car has performed faultelssly on many occassions and always brings a smile to my face. Stick with it matey. Mark
Funny you should say that... I have a leak coming from the timing cover...

Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 9:01 am
by tomkidd
It was a brand new weber so I am hoping it should be fairly easy to clean out. I'm going to investigate further and take it apart like richspec says.
Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 9:30 am
by Astro
Hi,
brand new - from Spain? There may happen some quality problems. Then there is only one solution, disassemble, control, assemble.
Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 9:34 am
by tomkidd
Astro wrote:Hi,
brand new - from Spain? There may happen some quality problems. Then there is only one solution, disassemble, control, assemble.
I am unsure as to where it is from, as the box was very old when I got it so it may be an Italian one
Re: Weber 45 DCOE - Uneven fueling
Posted: Wed Aug 29, 2012 2:40 pm
by Richspec
we had a brand new one that came apart - hence the comment about checking the securing screws on the underside..We also suffered a mini specialist fitting dellorto rampipes, and a rolling road that fitted differant sized mains on either side of the carb...
Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 9:17 am
by tomkidd
So... after falling out with the car, this morning I whipped off the brass cover and found this to be loose

Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 9:45 am
by guru_1071
thats a cheap fix then tom!
Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 9:50 am
by tomkidd
guru_1071 wrote:thats a cheap fix then tom!
Ha ha, yeah. I hope so.
How has it come loose though?
Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 10:34 am
by guru_1071
tomkidd wrote:
How has it come loose though?
not been tightened up in the first place would be my guess
Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 4:45 pm
by Red1967
Hi Tom
I am running a Weber 45 152. Which I found out has a design flaw. I had a major hesitation just off idle. The issue was the progression hole was not aligned over the butterfly valve. Once I drilled two new holes my carb worked great.
Join this site for a wealth of information.
http://autos.groups.yahoo.com/group/sidedraft_central/
Keith Franck has so much knowledge regarding webers. Even designed his own tubes and jets which I am going to try out next season. Spent to much time trying to get the mini running right, I do not want to screw it up this late in the season.
Cheers
Todd
Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 6:58 pm
by minicentie
Make sure you secure a lot of the fixings,on older carbs almost all the bolts and nuts have holes to wirefix.
It is better to take it apart and reassemble yourself ,and make sure it looks to be allright when you ,put it together.If something doesn't want to go in or misline ,it is something to look at.
The old carbs are very good,even after 40 years.
The new ones are rubbish,ough casting,bad allignment and poor build.
Re: Weber 45 DCOE - Uneven fueling
Posted: Thu Aug 30, 2012 7:31 pm
by Richspec
tomkidd wrote:So... after falling out with the car, this morning I whipped off the brass cover and found this to be loose

you appear to be missing the air filter as well

Re: Weber 45 DCOE - Uneven fueling
Posted: Fri Aug 31, 2012 9:31 am
by tomkidd
Richspec wrote:tomkidd wrote:So... after falling out with the car, this morning I whipped off the brass cover and found this to be loose

you appear to be missing the air filter as well

Ha ha, I've been told not to bother...? Would you?
Re: Weber 45 DCOE - Uneven fueling
Posted: Fri Aug 31, 2012 9:41 am
by Tim Harber
Is yours on a short manifold?
When we put the Weber on my historic car , it's never too happy on it's short manifold rammed up aginst the bulkhead- runs unevenly and all. It had been on my white car before on a long inlet with an air box , so besides not making the the usual induction whooorrrr noise, some conclusion must be drawn from that. It produces way more power than the SU's on the rollers and I tend to put it whenever we're at a quick track but in actual use it's never quite that obvious
Also, it's quite easy to spot Spanish webers: The are cast with "Made in Sp..