Car is running rich. Tech suggests stepping down from 140s to 30s. Can anyone help?
Thanks
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Car is running rich. Tech suggests stepping down from 140s to 30s. Can anyone help?
Thanks
Thanks
I'm pretty sure you can still get jets from www.cbperformance.com
or www.cip1.com.
Greg B
or www.cip1.com.
Greg B
Running too rich WHERE? You may need smaller IDLE jets, or your float levels may be too high, or your fuel pressure too high, or float needles and seats leaking. Or, your spark plugs may be too cold.
Don't know who your tech is, but you should start at the beginning...
Don't know who your tech is, but you should start at the beginning...
Yeah, Listen to George - he's absolutely right.
The FIRST thing to do is clean or replace your air filter elements to make sure they're not clogged and choking it slightly.
Then, make sure your chokes are fully open (if you have them at all).
Then get the timing set correctly for your engine, what ever that's supposed to be.
THEN make sure the idle jet circuit is set correctly (idle mixture screws, then idle jets, then accelerator pump stroke or jet) by using a quality air/fuel mixture gauge (CB Performance has them for about $100, or a lot of garages have portable units, typically from Sun Instruments).
Once the idle is set correctly for something between 12 and 14, then everything else built off of that.
Set you idle speed to what you want (typically between 800 and 1,000 rpm) and use a Unisyn or equivalent to match air flow through the carbs on both sides of the engine (to balance them), matching the idle air flow by adjusting the linkage.
NOW you can start playing with your Main jets.
What displacement is your engine, and what type (maker) and size are your carbs? 140 mains sound about right for 80% of VW applications.
The FIRST thing to do is clean or replace your air filter elements to make sure they're not clogged and choking it slightly.
Then, make sure your chokes are fully open (if you have them at all).
Then get the timing set correctly for your engine, what ever that's supposed to be.
THEN make sure the idle jet circuit is set correctly (idle mixture screws, then idle jets, then accelerator pump stroke or jet) by using a quality air/fuel mixture gauge (CB Performance has them for about $100, or a lot of garages have portable units, typically from Sun Instruments).
Once the idle is set correctly for something between 12 and 14, then everything else built off of that.
Set you idle speed to what you want (typically between 800 and 1,000 rpm) and use a Unisyn or equivalent to match air flow through the carbs on both sides of the engine (to balance them), matching the idle air flow by adjusting the linkage.
NOW you can start playing with your Main jets.
What displacement is your engine, and what type (maker) and size are your carbs? 140 mains sound about right for 80% of VW applications.
I called CB and they did have the jets.
Since I let the engine builder do all of the tests I will go by his diagnosis althoiugh I appreciate the input. I have been dealing with this challenge for some time and I did find an update kit that is suppposed to eliminate the constantl idle jet plugging problem with Dells. (they are spendy however)
The car runs fine however the plugs are a little on the dark side. Logic was Jet should be tween 130--135. We will try the 130s and then start drilliing until we come to perfect color. \When I have an engine built I just follow the orders cause I do not want the builder coming back at me under warranty.
Since I let the engine builder do all of the tests I will go by his diagnosis althoiugh I appreciate the input. I have been dealing with this challenge for some time and I did find an update kit that is suppposed to eliminate the constantl idle jet plugging problem with Dells. (they are spendy however)
The car runs fine however the plugs are a little on the dark side. Logic was Jet should be tween 130--135. We will try the 130s and then start drilliing until we come to perfect color. \When I have an engine built I just follow the orders cause I do not want the builder coming back at me under warranty.
Ralph, to eliminate idle jets getting fouled with crud install a cannister EFI style fuel filter and make sure the integrity of your air filters is 100%.
To see what's happening as you drive, install an Air/Fuel Ratio Monitor to determine jetting. (CB performance, Summit racing, and many other supply outlets have them)
That's one way you can track what's happening as it happens.
I found that having the guage provides a great comfort zone as it takes the guess work out of jetting.
As you're cruising down the expressway, you can watch whats happening with the carbs and jets at that particular speed, load, and RPM.
Greg B
George:
What is a "cannister" style filter. I have one of those see thru styles with the disposable inards. Costs $6 which is $5 more than the little plastic and paper jobs. That is all I am aware of.
What is a "cannister" style filter. I have one of those see thru styles with the disposable inards. Costs $6 which is $5 more than the little plastic and paper jobs. That is all I am aware of.
Metal canister EFI fuel filter as installed on new VW's, BMW's, Mercedes Benz, etc. Get rid of the cheap plastic crap and change the EFI filter every 10,000 miles.
thanks for enlightening me.