new carb issue - i think |
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new carb issue - i think |
william1764 |
Mar 5 2011, 10:29 AM
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#1
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Member Group: Members Posts: 252 Joined: 11-May 10 From: maryland Member No.: 11,717 Region Association: MidAtlantic Region |
Finally corrected the serious backfire issue i had (IMG:style_emoticons/default/cheer.gif) exhaust leak was found (crack at header mount flange area) and repaired...long story but excessive/loud backfire on decel has been FINALLY eliminated. Overnight however i developed a sputtering/popping thru carbs. Uneven and rough acceleration up thru 3k RPM and higher. idle is irregular but constant - either a little high or a little low but steady...varies on the day. I have noticed since the carbs were rebuilt last september fuel mixture out of the exhaust at startup...i assume too rich? new plugs already dark. i've only put on a couple hundered miles since carb rebuild so not much experiance since rebuild.
what could happen to cause the engine/carbs to take such a drastic turn from one day to the next with touching them? Could this be valve issue? for those not familar with past issues my set up is 74 2.0 with weber dual IDF 40's. on another note, anyone in balt/dc going to hershey? |
NJ914Guy |
Mar 5 2011, 10:33 AM
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#2
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Member Group: Members Posts: 150 Joined: 30-December 10 From: Deptford, NJ Member No.: 12,546 Region Association: MidAtlantic Region |
Have you checked the wires, cap and rotor? Also is the timing off?
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BarberDave |
Mar 5 2011, 11:01 AM
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#3
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Barberdave Group: Members Posts: 1,605 Joined: 12-January 03 From: Wauseon Ohio Member No.: 135 Region Association: Upper MidWest |
(IMG:style_emoticons/default/smilie_pokal.gif)
Check the idle jets, easy to remove just be carefull not to loose the O ring, it can stick to the carb or to the jet, it's better to have something under them or you will play Hell finding them on the engine or ground. When you remove them holed them up to the light to check for dirt , blow them out and replace. I am know expert be I think it runs on the isle circuit up to 3,000. They are very small and plug easly. It would be a good time to replace the fuel filter. There right at the base on the outside ,( towards the fender ) easy to find. Finger tight Mine did the same ,worked perfectly after , good luck ! Let us know, results. Dave (IMG:style_emoticons/default/slap.gif) |
william1764 |
Mar 5 2011, 12:21 PM
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#4
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Member Group: Members Posts: 252 Joined: 11-May 10 From: maryland Member No.: 11,717 Region Association: MidAtlantic Region |
I'll try the above and post results. Thanks gents
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VaccaRabite |
Mar 5 2011, 05:27 PM
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#5
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En Garde! Group: Admin Posts: 13,616 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
You may be jetted a bit rich and fouling plugs.
Does the idle get better if you drive it hard and get it hot, and then get shitty again when you start puttering around town or get stuck in stop and go traffic? Zach |
jmill |
Mar 5 2011, 09:42 PM
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#6
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
I'd check the idle jets first as already mentioned. Check pump jets for even spray. A stuck pump jet check valve will cause lean pops and poor acceleration. A linkage out of adjustment will also cause similar issues.
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william1764 |
Mar 6 2011, 07:40 AM
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#7
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Member Group: Members Posts: 252 Joined: 11-May 10 From: maryland Member No.: 11,717 Region Association: MidAtlantic Region |
You may be jetted a bit rich and fouling plugs. Does the idle get better if you drive it hard and get it hot, and then get shitty again when you start puttering around town or get stuck in stop and go traffic? Zach I wish that were the case Zach...much worse than that now. i would say that was how she was ran until the other day - before the current sypmtoms. i'm going to dig in today - raining like shit here so stuck inside anyway. I know that i can get to the idle jet but to access others does it require that the carbs be torn down? |
william1764 |
Mar 6 2011, 07:43 AM
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#8
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Member Group: Members Posts: 252 Joined: 11-May 10 From: maryland Member No.: 11,717 Region Association: MidAtlantic Region |
I'd check the idle jets first as already mentioned. Check pump jets for even spray. A stuck pump jet check valve will cause lean pops and poor acceleration. A linkage out of adjustment will also cause similar issues. thanks. is there an easy way to tell if linkage out of adjustment? |
seebobgo |
Mar 6 2011, 12:00 PM
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#9
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Member Group: Members Posts: 384 Joined: 14-December 05 From: Millersville, Maryland Member No.: 5,273 Region Association: MidAtlantic Region |
I'd check the idle jets first as already mentioned. Check pump jets for even spray. A stuck pump jet check valve will cause lean pops and poor acceleration. A linkage out of adjustment will also cause similar issues. thanks. is there an easy way to tell if linkage out of adjustment? I can't get my car a right either. 3.2 87 Carrera engine with 46 PMO's. Same symptoms as yours. It's been to 3, count them, 3 shops in the past two years. I have an old aquatint, up in Summit Point I'm thinking of giving a call. |
jmill |
Mar 6 2011, 02:20 PM
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#10
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
is there an easy way to tell if linkage out of adjustment? Use the search function on this site and you'll get boat loads of weber tech and tip info. Below is one I found that should help you out. http://www.carburetorclinic.com/weber_tech.htm |
seebobgo |
Mar 6 2011, 02:32 PM
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#11
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Member Group: Members Posts: 384 Joined: 14-December 05 From: Millersville, Maryland Member No.: 5,273 Region Association: MidAtlantic Region |
is there an easy way to tell if linkage out of adjustment? Use the search function on this site and you'll get boat loads of weber tech and tip info. Below is one I found that should help you out. http://www.carburetorclinic.com/weber_tech.htm Thank you (IMG:style_emoticons/default/grouphug.gif) but I don't tinker anymore. I'm going to look for a shop that I can have it transported to and get it sorted out. |
william1764 |
Mar 6 2011, 07:14 PM
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#12
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Member Group: Members Posts: 252 Joined: 11-May 10 From: maryland Member No.: 11,717 Region Association: MidAtlantic Region |
is there an easy way to tell if linkage out of adjustment? Use the search function on this site and you'll get boat loads of weber tech and tip info. Below is one I found that should help you out. http://www.carburetorclinic.com/weber_tech.htm great link...thanks jim (IMG:style_emoticons/default/bye1.gif) |
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