carb issue???

LT'sCharger

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I am having issues with our 72 Charger. We bought it from a widow and brought it home in March. It has sat mostly since 2017. Ever since the day that we brought it home, It was hard to start. I had to crank it and pump the pedal a lot to get it to start. Now, starting last week, it will not start at all. When I pour a little gas in the carb, it starts right up. If I rev it a bit and keep the RPM's up, it will continue to run. I have done this for several minutes, just to confirm that it is really getting gas and the fuel pump is working. As soon as I let off the pedal and it returns to idle, it slowly stalls. Once it stalls, it will not start again until I pour more gas in the carb. When I look inside the carb while I move the throttle manually, I see no fuel squirting from any accelerator pumps. To be honest, I am new to mopars and this is the first thermoquad that I have looked at, so I am not even sure if I should be able to see fuel squirting from the accelerator pump. I am thinking that the idle is too lean and that the accelerator pumps are not working. Also, one additional thing to note is that the car has been VERY weak when starting off the line. Once I am rolling and the RPM's are up, it accelerates nicely, but from a dead stop, it has no guts at all. Also, there appears to be a vaccuum port on the front of the carb that has no hose or no plug. Could this be a problem?

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Red63440

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Sounds like you need to have the carb rebuilt. Sitting like it did can always cause carb issues of some sort, things dry out.
 

R413

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Does it have 4 year old gas in it? Yes any open vacuum port is not good, plug it. Yes you should be seeing gas from the accelerator pump.

run a hose from the inlet of the fuel pump to the a can of new gas and see if it runs better.

As above the carb Probably needs a rebuild.
 

Ron H

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yeah - things may have gummed up + maybe skanked gas in the tank. Replace the fuel filter as it could be clogged as a simple start on the issue. You can run engine cleaner through the carb to see if this helps with engine running. The jets could have gummed up...indication of no squirting; couple simple things to try before having to get more invasive...
 

LT'sCharger

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The car has had at least 3 or 4 tanks of gas run thru it since we brought it home. We have driven it a lot.
 

Ron H

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The open vac port, as posted, is a red flag. Assume you’ve plugged it? You could check this if you can keep the motor running by holding your finger over the port and see if there’s vacuum…that should alter the running of the motor. But, are there any other lines possibly disconnected…or lines cracked or collapsed? Are you seeing the jets squirting now? If no, there’s a fuel delivery clog or lack of delivery causing the problem. Floats in the carb could be sticking from being gummed up. Eons ago I had a thermo on my ’73 Challenger and eventually poor running, no start…found a pinhole in a float (I was never a fan of this carb anyway). Installed a Holly and that car never ran better. Also if not done, given the history you mention, do a complete tune up on it and check carb adjustments, vacuum, reluctor gap, timing, etc. I’d get a new cap, wires, plugs. I’ve used Marvel oil in the gas and oil, old school guy that I think have given some desired results.
 

beanhead

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Well...I left about 8 oz. of gas in a pan on the side of my house, within a week it had turned to dark yellow varnish...so considering what today's gas does after sitting Ima thinkin' a full fuel system flush is in order first (because it's mostly just labor.) Drop the tank and flush it out real good, and give the sending unit/sock a good checkout. Clean the hardline (or lines) out and replace if necessary, and I'd simply replace any rubber portions because that's cheap. New filter. Pull the carb apart and clean and re-gasket it (or get someone to do that if you're not comfortable).
 

Ron H

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Well...I left about 8 oz. of gas in a pan on the side of my house, within a week it had turned to dark yellow varnish...so considering what today's gas does after sitting Ima thinkin' a full fuel system flush is in order first (because it's mostly just labor.) Drop the tank and flush it out real good, and give the sending unit/sock a good checkout. Clean the hardline (or lines) out and replace if necessary, and I'd simply replace any rubber portions because that's cheap. New filter. Pull the carb apart and clean and re-gasket it (or get someone to do that if you're not comfortable).
One of the reasons I run eth free gas every couple tanks and before I store it for the winter. It's a 35 mile ride for me to get this gas - as long as this is STILL available..
 

Ranger16

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When I look inside the carb while I move the throttle manually, I see no fuel squirting from any accelerator pumps.


Also, one additional thing to note is that the car has been VERY weak when starting off the line. Once I am rolling and the RPM's are up, it accelerates nicely, but from a dead stop, it has no guts at all.
Both comments make me think it needs a new accelerator pump plunger.


Also, there appears to be a vaccuum port on the front of the carb that has no hose or no plug. Could this be a problem?
Absolutely. As mentioned above, if it's not used, cap it.
 

LT'sCharger

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I think I am going to pull the carb and rebuild it. I will be at the Chrysler Nationals this weekend. What do I need to know to get the correct rebuild kit for it? Thanks.
 

LT'sCharger

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I bought a rebuild kit from an Ebay vendor that was recommended on the E body forum. I tore it down yesterday and did the rebuild. It is running great.
I drove it to the local car show and won a 2nd place trophy in my 70-79 class.

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