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bron Alfa Arna
Joined: 19 Jul 2003 Posts: 24 Location: Tasmania, Australia
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Posted: Sun Sep 21, 2003 11:24 am Post subject: fuel efficieny - what's that!!!??? |
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I'm not sure if it's the car, or my shrinking budget but I swear it's going through fuel faster than it used to. I measured it the last time I filled up and I'm getting 6 k's per litre (she's an 85 33, 1.5L twin carb). I've been driving it very gently, coasting down big hills either in neutral or with the engine off and not revving a great deal (if anything i've got a tendency to under-rev, I grew up driving an automatic). It's been tuned recently and it's not running rough or anything. Is this normal? I though 6kms/litre was pretty heavy for what is about 50/50 suburbs and highway driving. It's not like I'm sitting in traffic burning fuel either, in tassie rush hour is like five cars!
I know alfa's go through a fair bit of juice, but what is average for this kind of car? |
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Ian M Green Cloverleaf
Joined: 13 Mar 2003 Posts: 911 Location: Bath Somerset
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Posted: Sun Sep 21, 2003 2:35 pm Post subject: |
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The official Alfa figures from the handbook for 1.5 say
6 litres per 100km at 90kph
8.5 at 120kph
10.7 for urban
I find a good way to check fuel consumption is to put the same amount in at every fill and then reset the trip. _________________ Presntly own
Red Abarth 500c |
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Dave_NZ Alfasud
Joined: 13 Mar 2003 Posts: 56 Location: Amsterdam, NL
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Posted: Sun Sep 21, 2003 10:40 pm Post subject: wow! |
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i have a 1987 1.7QV and around town i drive pretty hard and get about 8km per litre. when on a long journey i get a return of about 14km per litre and that is driving quite fast. i suggest getting a tune up as when my carbs were out of tune it was very inefficient.
Dave _________________ Looking for a type 2 33QV in NL |
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Scott Sander Alfa 33
Joined: 20 Feb 2003 Posts: 419 Location: Sydney, Australia
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Posted: Mon Sep 22, 2003 5:00 am Post subject: |
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Worth having a look to see that the choke/cold starting device is not stuck open. _________________ Scott Sander
'91 Alfa 33 Boxer 16V Monza - Awesome
http://www.sanderfamily.com |
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Ian M Green Cloverleaf
Joined: 13 Mar 2003 Posts: 911 Location: Bath Somerset
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Posted: Mon Sep 22, 2003 8:54 am Post subject: |
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I just had my car MOT'D and they made some adjustments to get it through the emissions test and now its running like a bag of shit.
When I asked them to retune it they said they couldnt do that as it wouldnt be legal.
Does anyone know what the standard settings for the mixture screws might be ? i.e. how many turns out?
So I have a staring point from which to start getting it back running something like it should. _________________ Presntly own
Red Abarth 500c |
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ak8635 Alfasud
Joined: 16 Apr 2003 Posts: 38 Location: London, UK
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Posted: Mon Sep 22, 2003 9:49 am Post subject: |
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i seem to do 160km-190km per 20 litr.
however i really press it hard (110 everyday) _________________ A112 |
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bron Alfa Arna
Joined: 19 Jul 2003 Posts: 24 Location: Tasmania, Australia
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Posted: Wed Sep 24, 2003 11:55 am Post subject: |
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so I gather that 6 kms per litre is pretty bad then? That's weird, cos I've just had it tuned and it hasn't changed. I'm pretty sure its not the way i'm driving. Is it possible to have a leak in the fuel system?
Quote: |
Worth having a look to see that the choke/cold starting device is not stuck open. |
but if that was the case, wouldn't it rev heaps? |
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BILL Alfa Sprint
Joined: 04 May 2003 Posts: 154 Location: TRIPOLIS GREECE
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Posted: Wed Sep 24, 2003 8:15 pm Post subject: |
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Hi,
if you had a leak first you could smell fuel and you probably had fuel spots under your car where you parked it.Even at the smallest suspect of a leak you should check it ,its a big danger. |
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Admin Site Admin
Joined: 19 Feb 2003 Posts: 1223 Location: Stafford, UK
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Posted: Thu Sep 25, 2003 5:34 pm Post subject: |
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Hi
My little 1.3 lhd car is appalling on fuel around town, doing about 20mpg (ie about 7km/L), doing about double that on long journies. The accelerator pumps on that are probably the cause.
All the best
Keith |
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Dave_NZ Alfasud
Joined: 13 Mar 2003 Posts: 56 Location: Amsterdam, NL
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Posted: Sat Sep 27, 2003 2:05 am Post subject: |
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bron wrote: |
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Worth having a look to see that the choke/cold starting device is not stuck open. |
but if that was the case, wouldn't it rev heaps? |
well, when i had the choke on one of my webers open and the other closed, it ran average, and guzzeled the fuel. i noticed the change when this was rectified. it also made a sucking noise which was due to the vacuum choke being open. also check your vacuum advance. cheers
Dave _________________ Looking for a type 2 33QV in NL |
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bron Alfa Arna
Joined: 19 Jul 2003 Posts: 24 Location: Tasmania, Australia
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Posted: Sat Sep 27, 2003 6:02 am Post subject: |
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thanks guys, i'll check it out |
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ak8635 Alfasud
Joined: 16 Apr 2003 Posts: 38 Location: London, UK
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Posted: Tue Sep 30, 2003 9:12 am Post subject: |
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had a huge leak during the weekend..
the pipe from the fuel filter to the distributor was split and the petrol was all over the engine!!
fixed it but i had to move through serious traffic to get home.. _________________ A112 |
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Scott Sander Alfa 33
Joined: 20 Feb 2003 Posts: 419 Location: Sydney, Australia
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Posted: Tue Sep 30, 2003 12:59 pm Post subject: |
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ak8635 wrote: |
had a huge leak during the weekend..
the pipe from the fuel filter to the distributor was split and the petrol was all over the engine!!
fixed it but i had to move through serious traffic to get home.. |
lucky you didn't end up setting it alight. Leaking petrol is not a good thing. _________________ Scott Sander
'91 Alfa 33 Boxer 16V Monza - Awesome
http://www.sanderfamily.com |
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GaryUK Guest
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Posted: Wed Oct 01, 2003 12:19 am Post subject: |
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Engine fires go out if you blow hard enough and stop the leak, I know from experience , checking the fuel return line which was infact returning fuel quite efficiently. I hated the yellow HT leads anyway, much better black on the drivers side. |
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Eddie W Alfa 33
Joined: 31 Jul 2003 Posts: 375 Location: new zealand
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Posted: Thu Oct 02, 2003 3:59 am Post subject: |
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Float levels play a big part in economy as they will richen the mixture throughout the range . If you have Dellortos, they have plastic floats that get heavier over time (they should weigh 10gms) and this allows the fuel level to rise. While a good tune job should pick this up, the boxers seem quite tolerant of over rich mixture and normally only shows up in the idle speed slowing, especially when sitting at the lights etc.
Regards Eddie |
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bron Alfa Arna
Joined: 19 Jul 2003 Posts: 24 Location: Tasmania, Australia
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Posted: Thu Oct 02, 2003 12:48 pm Post subject: |
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i'm pretty sure it is running too rich - it spits out fine black spots out the exhaust. I also noticed that it is slower than usual to return to idle speed - it's like the rev's are lingering when I go into neutral. I've had a bit of a look at it - but it's a bit beyond me (yea, i'm a girl!) so i'm getting it checked out next week. thanks everyone though.
also - I had a problem with the foamy stuff in the oil cap a while ago, well the mechanic said that it is water, coming in through the air intake. Tassie's been really damp this winter and lots of other cars have had it. It comes in, evaporates and rises to the highest point - the cap. The dipstick shows that the rest of the oil is fine, it's just on the cap. So there's another mystery solved - maybe! |
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Scott Sander Alfa 33
Joined: 20 Feb 2003 Posts: 419 Location: Sydney, Australia
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Posted: Fri Oct 03, 2003 12:28 am Post subject: |
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Those black spots out the exhuast could be condensation in the exhaust system. This is normal. Does it still occour after the car has been running for awhile? _________________ Scott Sander
'91 Alfa 33 Boxer 16V Monza - Awesome
http://www.sanderfamily.com |
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Dave (Minari) Alfasud
Joined: 26 Jun 2003 Posts: 37 Location: Bexley, Kent
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Posted: Fri Oct 03, 2003 9:33 am Post subject: |
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What was done by the 'mechanic' originally? Did he/she/it change the carb top gaskets.
I did a carb refurb and then suffered all sorts of problems. not least the fuel consumption went from 38mpg to 22-23 mpg.
It blew wet black soot, and the pickup from a trailing throttle was nasty to say the least. A huge flat spot.
It turned out that I had the wrong gaskets and a hole which should have been there wasn't. Once I compared the old with the new I could see the difference and then used a small hole punch to make the required hole. All back to normal now. And a nice pick up from the trailing throttle.
Dave _________________ Retired and working harder than when employed!!! Crap at golf- "Stupid Bl**dy game!" |
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bron Alfa Arna
Joined: 19 Jul 2003 Posts: 24 Location: Tasmania, Australia
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Posted: Fri Oct 03, 2003 2:41 pm Post subject: |
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re the black spots - i'm not sure. I'll check whether they go away after a long run. That's been happening for ages though - at least a couple of years I think, the first time i noticed it was when it splattered all over my wedding dress as I was loading presents into the boot after the reception!
I'm not sure what the 'mechanic' has done, but yeah i have noticed higher fuel consumption, a flat spot in 2nd and 3rd at 2000/3000rmp whereas previously that was where it really started to take off - it isn't a stark difference though so i'm not sure if it was before or after i got it tuned by those guys. It was so badly out of tune beforehand that I would've put down any weird stuff I noticed to it being out of tune. I'm taking it somewhere else next week though- so hopefully they'll pick up if the other guys stuffed it up.
just out of curiosity, what does it mean to be running rich? does that mean there is a greater ratio of fuel to air going in? |
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Dave (Minari) Alfasud
Joined: 26 Jun 2003 Posts: 37 Location: Bexley, Kent
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Posted: Sat Oct 04, 2003 1:25 pm Post subject: |
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The flat spot I refered to was only on the change over from a foot off the right pedal to making the engine some work, (other than engine brakeing)
Running rich- Yes your description is about right. The fuel/air mixture has too much fuel for complete and clean combustion.
The opposite is a lean or weak mixture.
The problem on my engine was that I had been supplied with the wrong gaskets for the Webers, the difference was very small. But the difference it to the engine made was large.
Dave _________________ Retired and working harder than when employed!!! Crap at golf- "Stupid Bl**dy game!" |
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