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Old 04-09-2020, 02:07 PM   #1
El Campo
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Need help with Rochester Monojet carb

After a long hiatus of working on my projects I’m back to fiddling with the online 6 250 in the original 72. The carb was all varnished up after years of sitting so took it all apart noting all settings and such and rebuilt it. Was meticulous about cleaning and soaked overnight in carb cleaner gallon. This morning I went through and made sure every single passage was spotless and could blow air through as well as run wire through gently. Put on the engine and gave just a bit of gas down the barrel to help fire off. Started right up and ran fine for about 15 seconds (half throttle) and then it started to have this rushing air sound and it died. I can get it to fire and run momentarily and then it dies again making the same sound. This electric choke setup on here is Greek to me. Also are these two ports in the following pictures supposed to be open? I plugged them with fingers while was running and didn’t help anything. Not 100
Percent sure I got the cams on the throttle and choke shafts quite right but I sure thought I had. Does anyone have pictures of theirs in a working arrangement? Thanks again, Matt
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2003 Harley Davidson Dyna Superglide with 2007 Street Bob front end
2000 Ford F350 Powerstroke 4WD CCLB, 310,000 miles running great (STOLEN St. Patricks Day 2014 AND NEVER RECOVERED)
2002 Ford F250 Powerstroke 4WD CCLB (To replace stolen one)
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Old 04-09-2020, 05:04 PM   #2
Steeveedee
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Re: Need help with Rochester Monojet carb

Make sure that you have the base gasket oriented correctly. If the ports you blocked are below the throttle plate (I think one is above, one below) and noticed no change when they were plugged, you have a vacuum leak somewhere else. It's easy to put the base gasket on wrong.
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Old 04-09-2020, 06:55 PM   #3
notsolo
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Re: Need help with Rochester Monojet carb

What about fuel filter?
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Old 04-10-2020, 08:33 PM   #4
El Campo
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Re: Need help with Rochester Monojet carb

I totally did away with the fuel filter just momentarily and no improvement. If nothing else comes up Im going to pull the carb again I think and check again. Wondering if maybe the float is set wrong and or is not letting fuel in. I did not change the needle and seat for fuel inlet because the kit I got didn't make any sense. I know I should have and looks like I will be going back into it again.
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72 Chevy blue LWB, 99% original Oklahoma truck, 28,000 miles
72 Chevy SWB: http://67-72chevytrucks.com/vboard/s...d.php?t=486626 (Attempt/Mistake #2)
2003 Harley Davidson Dyna Superglide with 2007 Street Bob front end
2000 Ford F350 Powerstroke 4WD CCLB, 310,000 miles running great (STOLEN St. Patricks Day 2014 AND NEVER RECOVERED)
2002 Ford F250 Powerstroke 4WD CCLB (To replace stolen one)
Hook em Horns!!!
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Old 04-10-2020, 09:16 PM   #5
67mater
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Re: Need help with Rochester Monojet carb

I dont see the pictures you reference but I have running monojet I can get you any picture you like.
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