Weber carburettor qualms!

**Bisho** · 21st January 2008, 10:24 PM

g'day all

i've got a few issues surrounding my weber carbie on my 2.25 petrol. ok 1stly.

To me it seems it drinks a lot of fuel (the fuel guage is dicky, but i'm still not getting very good mileage). I know they aren't the most efficient or aerodynamic of beasts, but i think this is a bit much. I know they are sluggish also, but i think mine might be a little overly so. When the engine is almost warm and i put the choke back in, i find it chokes a little or splutters in low revs, is this normal?

1. I'm not exactly sure if its the carbie or not, but when cold there seems to be a lot of black, unburnt fuel coming out of the exhaust until the engine reaches operating temperature. I've fiddled with the idle mixture setting a tad, making it leaner and so on, but still there is unburnt fuel. I know someone who had as 11a, who said he also had the problem of stinking up the neighbourhood and using a lot of fuel (think he had a solex), but he changed the jet in teh carbie to a 0.25mm or something or other, and bingo, now it runs like a gem, he reckons he can spin the wheels in 1st and 2nd! I dont know if i beleive him, but i do know his has only got 33k original miles on it.

I also have genie extractors on the car ( which i didnt recognise for ages!) which if anything, i think would help effeciency!

So if anyone has any ideas, or theories, i'd love to hear them. I've also heard conflicting evidence regarding weber carbies in that, some sources say they are more effecient when driving at lower throttle movements as they are a 2 barrel carburettor (i drive as conservatively as i can). And thus this makes the weber less responsive (less performance). While other sources say weber's do enhance performance but inhibit economy. I've heard solex's can get better mileage?

either way, i know there were some fuel probs with the car with the prev owner, which is why he fitted an electronic fuel pump and the weber carbie.

sorry it's an essay!

cheers!

john

**JDNSW** · 22nd January 2008, 05:29 AM

I have no experience of the Weber, but any of the OE carburetters perform well when in good condition and properly adjusted. Certainly it should not be producing black smoke. It is possible, if it has a non standard fuel pump, that the fuel pump is producing a higher pressure than the carburetter is designed for, but I would not expect that the problem is in the carburetter itself, although this may be compounded by incorrect timing or other problems. For example, there may be a manifold air leak which has been compensated for (at some speeds) by larger jets.

John

**Bisho** · 22nd January 2008, 10:31 PM

thanks john, your the man.

just out of curiosity, what mileage do you get in your 2.25 petrol, L/100km?

i will look into it.

**JDNSW** · 24th January 2008, 06:44 PM

Originally Posted by Bisho

thanks john, your the man.

just out of curiosity, what mileage do you get in your 2.25 petrol, L/100km?

i will look into it.

I'm afraid I really don't know - it is used almost entirely around the farm, and I don't keep detailed fuel records. It would be around 20l/100km, but you have to realise that little of this is in top gear, and quite a lot in four wheel drive, and none on sealed surfaces.

John

**lro11** · 24th January 2008, 07:10 PM

I have a friend who had one on his car he said he changed the main jet because the carbie was for a 6cyl

**Bisho** · 24th January 2008, 07:46 PM

thats very interesting lro11. i have always thought this was the weber designed for the 4 cylinder petrol, but i may be wrong. do you have any idea what size jet he changed to?

cheers mate!

**lro11** · 24th January 2008, 08:02 PM

No idea sorry my land rover manual says the petrol consuption should be 680ltr/5000km

**Bisho** · 24th January 2008, 10:39 PM

cool man. ( u should get him on the forum!! wink wink nudge nudge). So i assume thats for the standard carbie (zenith or solex...etc) is that for highway or city driving?

**LandyAndy** · 25th January 2008, 06:38 PM

To check for manifold leaks get a can of CRC and fit the tube that comes with it.
With the engine runing spray all the joints between the inlet manifold and head and between the manifold and carb.
If there is a leak a change in engine revs will be evident when the spray is applied.
Goodluck
Andrew

Thread: Weber carburettor qualms!

Thread Tools

Weber carburettor qualms!

Bookmarks

Bookmarks

Posting Permissions