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chocolate.curry
I just pulled my 914 out of storage and it started right up (well almost). It was a little hard to get going, but ran fine on the way home except for intermittent snap/crackle/pop. I can swear I hear both backfiring in the tailpipe and popping in the carbs. I was told last year before I put it away that it could be worn rings (Ed at CFR), but I want to eliminate other stuff if I can first, because it actually drives pretty well. I love flogging this car dead horse.gif , it doesn't complain and just keeps asking for more at higher RPMs. At lower RPMs it surges a little and generally is not very enthusiastic.

So -- how do I clean the idle jets? I've worked on carbs on a motorcycle before but never on a car. I've searched but can't find a good thread that gives specific enough instructions; maybe I need a manual, but don't have one yet (which one should I get?). I'll move on to checking exhaust leaks after I do this (and then more serious carb issues, or engine work mad.gif). I guess I should check the timing as well (where is the timing mark?) Thanks in advance for helping a newbie!

Ram
carr914
I'm including a picture of a 911 carb, but the process is the same. Unscrew the idle jet #4 in this picture (make sure the rubber grommet comes out with it), seperate the base from the jet and spray the hell out of it with carb cleaner. Spray cleaner in the hole and re-assemble.

T.C.

Click to view attachment
type2man
Before you blow it out, look to see if it has crap at the end of it. If it doesn't then either the crap might have fallen off the tip before you unscrewed it and will get back onto the tip after you start it or that is not your problem and you might need to further diagnose it...
So.Cal.914
Pull your idle and main jets. Use carb cleaner with the nozzle and blow down through where the mains go and in the side of the carb where you removed the idle jets. I use a piece of wire from a wire brush to clear anything that might be in the jets and then blow carb cleaner through them. Wear safety glasses, the carb cleaner will shoot back at you sometimes when shooting into those small passages.
If they have been sitting for a while, I would put some rebuild kits into them. The float needle and seat can get messed up and leak.
chocolate.curry
QUOTE(carr914 @ Apr 27 2009, 07:11 PM) *

I'm including a picture of a 911 carb, but the process is the same. Unscrew the idle jet #4 in this picture (make sure the rubber grommet comes out with it), seperate the base from the jet and spray the hell out of it with carb cleaner. Spray cleaner in the hole and re-assemble.

T.C.

Click to view attachment


Awesome, this is exactly what I needed! What is the "clean out plug" for??
rhodyguy
one of these cans of compressed air are pretty handy for blowing out jets, unless you like the taste of fuel. as your car seems to run well when you're on the mains the idles are the place to start. when cleaning the jets, blow from the seated end back.

the idle jet holders are the brass, slotted head units to the side of the fuel inlets. one on each side, 2 per carb. be careful when removing the jets, there is a little o-ring for each jet assem. don't lose them.

on the bottom of the carbs, the idle air adjustment needle screws are the ones with the springs. sounds like you need to invest in a weber book. the one offered by CB performance is a dandy.

jmill
Before you do this slowly turn the adjustment screws in until they bottom out. Don't mash them down on the seat. Just screw them in until they touch. Count how many turns they are off the seat. That way you can put them back where they belong after you clean them up. You might have to tweak them a little but at least you'll be close.
ruddyboys
Is the idle jet location in the same place on Dells?
charliew
What if it's just old gas? Why not first add some fi cleaner to the gas and top it off with new good gas and run that through it first. I know it may take too long but thats better than dropping something and not being able to find it and really getting into removing the carbs and starting a new career in rebuilding carbs. Although you will so proud of yourself when you can speak carb technology fluently.
chocolate.curry
QUOTE(charliew @ Apr 28 2009, 03:02 PM) *

What if it's just old gas? Why not first add some fi cleaner to the gas and top it off with new good gas and run that through it first. I know it may take too long but thats better than dropping something and not being able to find it and really getting into removing the carbs and starting a new career in rebuilding carbs. Although you will so proud of yourself when you can speak carb technology fluently.


yeah it started running poorly last summer... I put in some seafoam and no dice, nothing changed. It's funny I'm way more familiar/comfortable with EFI due to my saab project, the carbs, well, just seem like a pain in the butt. but that's what's in the car... i'll give cleaning the idle/main jets a shot and see where that takes me.
johnnie5
Maybe I missed it, did you say what carbs you are running? Here is a link to a great page I found awhile ago for Webers. Good luck...

http://www.piercemanifolds.com/tech_spec.htm
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