Dual Carb Problem need help |
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Dual Carb Problem need help |
Cazz |
Mar 17 2018, 12:38 PM
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#1
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Newbie Group: Members Posts: 13 Joined: 22-December 16 From: NC Member No.: 20,688 Region Association: None |
Any carb specialists out there? I need help with a carb problem.
-1974 2.0 with dual weber carbs -The car is spitting and popping out the carb on cylinders 1&2and also backfiring alittle. I've rebuilt the carbs and pulled this carb off again completely taking it apart and checking with no obvious issues found -With the car idling when I put my hand over each barrel on this carb there is no suction at all on my hand. The idle doesn't drop at all. Doesn't respond to any adjustments on the fuel/air mixture screws. -The carb is injecting fuel streams when I open the linkage by hand -On the carb on the opposite side when I put my hand over each velocity stack it really pulls air really hard on my hand and the car will bog down and shut off as it should. -I have new intake gaskets an new carb base gaskets installed. I sprayed carb cleaner around the base of the carb and also at the head with no change in idle. Any ideas? Is this car basically running on 2 cylinders? -On the opposite carb on cylinders |
barefoot |
Mar 20 2018, 06:27 PM
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#2
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Senior Member Group: Members Posts: 1,273 Joined: 19-March 13 From: Charleston SC Member No.: 15,673 Region Association: South East States |
I'm having sync problems as well Dell 40's on new build 2056.Web 494 cam valve lash just re-set after cam break-in .006+ intake, .008+ exhaust 115-120 compression across all 4 cyl. Timing set to 27 Deg at 3500 but getting popping back thru #1,2 and suddenly, no idle fuel to #4. have open exhaust thru SSI's so can feel temperature at each outlet. have cleaned carbs several times but no improvement.
Have studied the Dell tech book over & over. Also can't seem to get idle below 1100, I've insured that butterflies have no more than .003 gap with closed throttle although one carb can't get as tight as the other. |
98101 |
Mar 20 2018, 08:13 PM
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#3
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Michael in Seattle Group: Members Posts: 373 Joined: 7-October 17 From: Seattle, WA Member No.: 21,495 Region Association: Pacific Northwest |
I'm having sync problems as well Dell 40's on new build 2056.Web 494 cam valve lash just re-set after cam break-in .006+ intake, .008+ exhaust 115-120 compression across all 4 cyl. Timing set to 27 Deg at 3500 but getting popping back thru #1,2 and suddenly, no idle fuel to #4. have open exhaust thru SSI's so can feel temperature at each outlet. have cleaned carbs several times but no improvement. Have studied the Dell tech book over & over. Also can't seem to get idle below 1100, I've insured that butterflies have no more than .003 gap with closed throttle although one carb can't get as tight as the other. I was having so much trouble with the beat up, fuel leaking, bent throttle shaft DRLA 45s that came with my car. While debugging the problem at a local VW shop, tried his new old stock DRLA 45s and instantly everything was better. After that I didn't want anything to do with my old ones so just bought his.... where they remain on my car. I'm liking the Dellortos now, but that book could use a rewrite. I also replaced my worn out hex bar linkage with a CSP bell crank linkage that looks good and is easy to adjust. |
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