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Posted by: chocolate.curry Apr 27 2009, 05:06 PM

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 , 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 ). I guess I should check the timing as well (where is the timing mark?) Thanks in advance for helping a newbie!

Ram

Posted by: carr914 Apr 27 2009, 05:11 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.

Posted by: type2man Apr 27 2009, 07:23 PM

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...

Posted by: So.Cal.914 Apr 27 2009, 08:23 PM

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.

Posted by: chocolate.curry Apr 27 2009, 08:43 PM

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.

Posted by: rhodyguy Apr 28 2009, 08:25 AM

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.




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Posted by: jmill Apr 28 2009, 08:44 AM

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.

Posted by: ruddyboys Apr 28 2009, 11:53 AM

Is the idle jet location in the same place on Dells?

Posted by: charliew Apr 28 2009, 01:02 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.

Posted by: chocolate.curry Apr 28 2009, 09:17 PM

QUOTE(charliew @ Apr 28 2009, 03:02 PM)

Posted by: johnnie5 Apr 28 2009, 09:40 PM

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