 help! carb/mixture/ignition trouble, not a mechanic |
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| lotus_65 |
  Aug 30 2005, 09:58 AM
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#1
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Senior Member  Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region  |
i had new webers 40's professionally installed about 5k miles ago. always seemed to run too rich for me, but the guy said it was right, so there. (he must be out of town, cause he ain't callin' me back)
about 2k miles ago i started getting some exhaust ignition of unspent fuel, and it's gotten progressivly worse. i finally pulled the plugs this morning and this is what i found: #1 black and sooty like the tailpipe #2 black and sooty too, threads are wet #3 brown and sooty, not as bad #4 gray, normalish the carbs on the 1/2 side look wetter & are collecting more debris than the 3/4, and the gaskets even look wet ( (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif) ) besides taking it to him for a big $, is there something i can start with to flesh out the issue? (i will have him do the major stuff) thanks a bunch |
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Replies(1 - 9)
| pfierb |
Aug 30 2005, 10:14 AM
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#2
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oldest member Group: Members Posts: 606 Joined: 1-May 05 From: The sign of good government in Connecticut is to keep raising taxes Member No.: 4,008 |
Hate to say but put the FI back if possible.....had the same problem with my 73 2.0 with weber IDF40s they would never run right every day was a new adventure in pooping, popping and running rough with lousy mileage....had the FI reinstalled by one of the good guys in this club EJM and it runs great fun to drive now.
Paul F. |
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| lotus_65 |
Aug 30 2005, 10:39 AM
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#3
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
yea, i've searched the threads here and it seems the overwhelming consensis is to go back to fi. i didn't keep the unit (dumba$$ me), so to get back in would just kill my wallet. i'd sell the car first actually, then tears would flow. in relative terms, the milage isn't bad. 15-17 city, and i just got back from a thousand + miles on the highway that gave me 27-29mpg! i'm takin' that, for sure. thanks for the advice, i'm definitly considering the options. |
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| SirAndy |
Aug 30 2005, 05:17 PM
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#4
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Resident German Group: Admin Posts: 41,675 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
looks like the jetting is off ... what are the numbers on the carbs? i mean, jet sizes, venturi sizes, emulsion tubes, etc. etc. etc. ... is the motor otherwise stock? (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif) Andy |
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| lotus_65 |
Aug 30 2005, 05:47 PM
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#5
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
i'll have to get them tomorrow, sir andy. i'm at work. bob said that it was set up to run a little lean in the cold, but it would be rich when it's hot weather. that's fine, but it's not hot now (mid 60's to 80) and it was happening when i drove it last week on a 48° night. the last time i spoke with bob, he agreed that we might have to re-jet. on hard acceleration it acts normally, but anything other than that and it's undriveable. engine's stock otherwise. something has changed (other than the jets i think) in the setup because it just happened out of the blue. i swapped out plugs to confirm good fire, but i don't have the gear to check anything else. my question it: can i just achieve a level of performance working only the mixture, or will i have to swap jets all the time? thanks again, and i'll get that info tomorrow. |
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| maf914 |
Aug 31 2005, 08:28 AM
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#6
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Not a Guru! Group: Members Posts: 3,049 Joined: 30-April 03 From: Central Florida Member No.: 632 Region Association: None 
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Once you get a good set up for the carbs you can leave it alone. As Andy said, post your engine specs and any mods to it and all of the carb data (venturi size, emullsion tube, main, idle, air correction and pump jet size) and chances are someone here will have a similar combo to help get you started. I used Weber 40 IDF's on a mildly modified 2.0 for years and was satisfied with the performance. |
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| lotus_65 |
Aug 31 2005, 09:49 AM
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#7
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
i'm glad you said that! i'm still waiting for a callback. thanks for the help in advance |
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| rhodyguy |
Aug 31 2005, 11:22 AM
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#8
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,090 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
tell us about your fuel pump. facet?, rotary? if facet, was a fuel pressure regulator installed? 1&2 share a common carb and they both sound the worse from your discription. with one idle adjust screw (either side), turn the idle up to 2k, check for equal flow with your syncronometer on the carb throats for cyl 1&4.
k |
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| lotus_65 |
Aug 31 2005, 07:40 PM
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#9
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
thanks.
bob thinks it's a float that has gone bad. he's going to road america with his team and won't be back until monday, when he'll pack my car up in his trailer and fix it. it was a brand new kit, and these guys are the real deal so i don't know what to think. i have been bugging him for months that it seemed the mixture was too rich, but he kept putting me off saying it was right. well long story, i'm miffed. and i don't want a big bill! but i've been washing the oil off the cylinders, i might be in for it. (IMG:http://www.914world.com/bbs2/html/emoticons/mad.gif) no details until tuesday at the earliest, but i really appreciate all the help. this is a great community. paul |
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| r_towle |
Aug 31 2005, 07:58 PM
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#10
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Custom Member Group: Members Posts: 24,588 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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type 4 motors are different that type 1 motors...
So,,,,post the sizes of your jets and venturis and tubes and we CAN help get it better. Rich |
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