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Need help with carb.

 
Old 07-11-2019, 09:59 AM
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nelson007
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Default Need help with carb.

I have a 1960 with all matching numbers, When I press on the gas easy all works well. The problem is when I press too hard it hesitates and almost stops the engine. I assume its flooding the engine. Also if I floor the car going about 30 in first it does the same when the 4 barrell kicks in. Sometime when doing this after picking up speed its starts to break down. The car only has 2800 miles on it.
Any advice will be appreciated.
Thanks,
Nelson
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Old 07-11-2019, 11:15 AM
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dplotkin
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Originally Posted by nelson007 View Post
I have a 1960 with all matching numbers, When I press on the gas easy all works well. The problem is when I press too hard it hesitates and almost stops the engine. I assume its flooding the engine. Also if I floor the car going about 30 in first it does the same when the 4 barrell kicks in. Sometime when doing this after picking up speed its starts to break down. The car only has 2800 miles on it.
Any advice will be appreciated.
Thanks,
Nelson
Nelson-
Sure sounds as though something's not right in the carb, but with old cars a myriad of problems can cause the same or similar symptoms. If you are not accustomed to "wrenching" on your old cars yourself may I suggest you get it in the hands of someone who works on old cars. Your problem could be a faulty accelerator pump, a distributor problem, a vacuum leak and everything in between. The car needs diagnosis. Do you have access to an older dude mechanic?

Dan
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Old 07-11-2019, 02:46 PM
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Dave Tracy
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May be that the accelerator pump is not working. To check the jets, see if you see the gas spray out of the nozzles when the accelerator is pushed to the max. You can check this with the engine off.
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Old 07-11-2019, 03:16 PM
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Dan Hampton
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Check the easy stuff first. Vacuum leak(s)/low fuel pressure.
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Old 07-11-2019, 05:45 PM
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Thanks for the info. I do get a spray from the car when I press down the throttle
I am going to put a vacuum meter on it tonight see if I could tune it in any better.
It takes so long in my area to get into a repair facility.
Thanks,
Nelson
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Old 07-11-2019, 05:49 PM
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Originally Posted by nelson007 View Post
Thanks for the info. I do get a spray from the car when I press down the throttle
I am going to put a vacuum meter on it tonight see if I could tune it in any better.
It takes so long in my area to get into a repair facility.
Thanks,
Nelson
In that case, may I recommend that you get your hands on a copy of the applicable shop manual for your car. The tune-up and troubleshooting sections in those manuals I find are very helpful in getting a car running, even for the non mechanic types.

Dan

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Old 07-12-2019, 06:34 PM
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nelson007
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Thanks Dan
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Old 07-12-2019, 08:18 PM
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While checking the easy stuff, check timing and vacuum advance. Very easy to do if you have the tools and know how to use them. After that, I would move on to the carb. When was the last time it was serviced? As was suggested, the old leather accelerator pump may have worn out. If you decide to service the carb, you will be into it for a rebuild by the time you get it apart far enough to replace the pump. Make sure they use one of the newer kits with ethanol resistant parts
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Old 07-13-2019, 12:44 PM
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boxster99t
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And another easy fix is if you have a fuel filter between the fuel pump and the carb (in my 67 Holley 3810 there's a fuel filter in the fuel inlet of the carb, don't know about C1's), replace it and see if that fixes the issue. What you described can be due to fuel delivery to the carb, as it doesn't take much disruption in the fuel line pressure to cause what you described.
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Old 07-13-2019, 05:45 PM
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cardo0
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An engine will stumble when it's drunk with fuel. It will bog when starved for fuel. To me it reads like it's stumbling. You can just try smaller jetting and a smaller pump shot - one step at a try.

The modern way of carb tuning is using a wide band air/fuel ratio monitors. They have become so inexpensive that it's difficult not justify owning one.

Let us know what works for you.
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Old 07-13-2019, 08:40 PM
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Frankie the Fink
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A bog from cruise is a faulty advance mechanism or secondaries opening too soon. If the carb is an original WCFB with the proper weights and springs and the car's vacuum is to spec the secondaries shouldn't be a problem. I would check the vacuum advance...



From "The Carburetor Shop" - they've only been doing this stuff for 45 years.

Last edited by Frankie the Fink; 07-14-2019 at 08:56 AM.
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Old 07-14-2019, 08:37 AM
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If all else fails, send it to Lars. I dealt with irritating tweaking on my carb for way too long. He set me straight.

Mike
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Old 07-14-2019, 03:26 PM
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PAmotorman
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if it has a WCFB carb make sure the weighted aux air valve in the secondary is working properly and not stuck open.
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