Help! Rebuilt Carbs, Now Engine Car Shudders at 4k RPM |
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Help! Rebuilt Carbs, Now Engine Car Shudders at 4k RPM |
'70PVW914 |
Nov 11 2013, 12:07 AM
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#1
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Newbie Group: Members Posts: 29 Joined: 1-November 13 From: Boulder, Co Member No.: 16,594 Region Association: Rocky Mountains |
Hey folks. I just rebuilt the weber IDF 44 carbs on my 914-2.0 because I was experiencing hiccups/stutters in acceleration from idle to about 3k rpm. Also, the car would idle very low, and then die if you did not give it a good amount of revs after starting. I figured my idle jets were clogged, and since the carbs had not EVER been rebuilt, I re-gasketed, and rejetted them.
Just finished that today, put in new fuel line to the carbs, changed the fuel filter, and troubleshot a strange problem where my accelerator cable seemed to wrap its way around the clutch cable and bind. :headbanger After all of that.....my car is STILL acting very strange; in some ways things are better, and in some, things are worse! NOW: The car seems to idle just fine at a very nice 900rpm after adjusting the idle and throttle body.----SWEET! The accelerator cable seems to stick slightly, also, the ball joint for my accelerator pedal seems to keep popping off of the pivot point (Is there a trick to this, or is the ball joint just shot?!) Seem to have it on there now, but now guarantees! ---LESS SWEET Still seems to stutter when reving in gear b/w idle and 2.5k rpm...same as before I rejetted and cleaned (IMG:style_emoticons/default/dry.gif) Shudders and looses power at 4k rpm in every gear...this thing had crazy power after 4k before I messed with anything. (IMG:style_emoticons/default/mad.gif) When I replaced the float needles and seats that came with the rebuild kit, I noticed the seats were way smaller on the rebuild. I DID NOT adjust the float level....my first culprit for this less than stellar performance. After reading some posts on here, it sounds like the float should be at between 12.5mm and 13mm from the upper face of the carb. Would this solve these problems? Also, I DID remove the throttle valves for a clean and inspection when rebuilding...I am hoping this is not the root of the problem, as they do not seem as smooth as they once were. Don't think its the resize in jets, as I just changed idles from .45 to .55, and air corrections from 200 to 190 as per recommendation. Where should I start here!!!????? I figure I will measure and adjust the float tomorrow, after I remove the carbs again (damnit). But if that doesn't work...what should I be trying?.....Damn weber book didn't get here in time and I am not the most patient..... |
ThePaintedMan |
Nov 11 2013, 06:48 AM
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#2
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States |
4K indicates something more towards the top-end of the carb. Is it possible you put your auxiliary venturies in backwards? This is very easy to do.
Yes, the floats absolutely need to be adjusted correctly. But not likely that is what's causing your issue, IMHO. Your settings should be somewhere around 11 mm with the gasket already in place and 32 mm dropped (without any tension). (IMG:http://www.914world.com/bbs2/uploads_offsite/www.poustusa.com-13527-1384174375.1.gif) You mentioned that you removed the butterflies, correct? Did you remove the throttle shafts? Also, do you notice any binding, and are the butterflies closing completely on both barrels? You can check this by shining a light down them and looking from the other side to see light (when the carbs are off the car and drained of course). If we could get a picture of the carbs, that might help with any immediate visual confirmation. We'll get you sorted out. You mentioned that you're not patient. Sorry, but owning a car with carbs, especially a 914 is going to require plenty of that. Nothing is going to get fixed all-at-once unfortunately. We've got to work through each issue systematically, but in the end you'll have an awesome reward for being patient (IMG:style_emoticons/default/smile.gif) |
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