|
Post by Charlie on Jan 30, 2019 12:01:38 GMT -5
Why is fuel dripping down the intake after shutting off the engine such an issue in these cars? My parents' Charger did it... my 72 318 Duster did it... and this Charger does it. I know 5 to 6 seconds is a very short period of time, but when your starter cranks for that long, people start to look at you and think "Dude is your car broke?" It surprisingly does seem like a long period of time when you're cranking!
I have two 1970's Ford trucks... one with a 300-6 and 1bbl carb, and the other with a 351M and 2bbl carb. Those two trucks always fire off the moment you hit the key... hot or cold... does not matter. There is no waiting for them to start.
But dammit... why are Chrysler products so bad about it?
|
|
DynoDave
CO-ADMINISTRATOR
Motown Mopar-Wizard
Posts: 11,163
|
Post by DynoDave on Jan 30, 2019 12:08:17 GMT -5
Does your Charger have a Thermo-Quad Charlie?
|
|
|
Post by Nacho-RT74 on Jan 30, 2019 12:26:43 GMT -5
Does your Charger have a Thermo-Quad Charlie? WHY COULD YOU THINK ON THAT? LOL
|
|
|
Post by Charlie on Jan 30, 2019 12:54:51 GMT -5
This car has a Quick-Fuel 650 4bbl. Although the original 4 bbl is in the trunk.
|
|
DynoDave
CO-ADMINISTRATOR
Motown Mopar-Wizard
Posts: 11,163
|
Post by DynoDave on Jan 30, 2019 15:08:22 GMT -5
I asked because there are a couple of common wear issues with TQs that could aggravate this condition. If you are boiling the fuel out of the carb after shutdown due to heat, blocking the crossover in the intake can help (if you still have that). Insulating fuel lines helps too. Are you using an insulating spacer of some sort under the carb? They can help too. For quick restarts after a hot soak, a small, low pressure electric fuel pump works wonders. It will refill those bowls in a matter of a second or so, greatly reducing cranking times. I used one of these years ago, from Whitney's, though it was not Holley branded. This one is extremely low pressure, and just a booster for starting. HolleyThis one offers slightly more pressure, but still well within the limits of what your carbs float, needle and seat can handle. Too much pressure overwhelms them. Spectra
|
|
|
Post by Nacho-RT74 on Jan 30, 2019 15:47:07 GMT -5
I asked because there are a couple of common wear issues with TQs that could aggravate this condition. of course... BTDT! plastic bowl uses to crack close to wells passages. That's why I laughed LOL
|
|
DynoDave
CO-ADMINISTRATOR
Motown Mopar-Wizard
Posts: 11,163
|
Post by DynoDave on Jan 30, 2019 17:13:56 GMT -5
Oh yeah. The TQ on my Chrysler has a vintage JB Weld repair for a crank. And yes, the well plugs could come loose and leak. Seems there were some o-rings inside too...
|
|
|
Post by Nacho-RT74 on Jan 30, 2019 20:26:00 GMT -5
Yes the glue cracks but that's an easy fix... problems come when bowl itself cracks too around there... BTDT too. Yes, they carry O rings there too
|
|
|
Post by Charlie on Jan 30, 2019 22:42:51 GMT -5
I do not think it's emptying the bowls... so I don't think a small pump for starting will have an effect. In fact, this carb has sight glasses for the bowls, so I think tomorrow I will get a visual on those glasses and see what happens after shutting down.
A spacer..... hmmm. Honestly, I don't recall if it has one or now. If not, I'll see about getting one.
The crossover setup is likely all in place. I think I saw one of the valves on the passenger side exhaust manifold. Do both sides get a valve? Or just one side?
I was looking at insulating the fuel line. I have some of that woven fiber stuff specifically for that purpose, but it will be difficult to get the line completely covered due to a T used to get the fuel to enter the carb at two different places... although I think I can get most of it covered.
|
|
DynoDave
CO-ADMINISTRATOR
Motown Mopar-Wizard
Posts: 11,163
|
Post by DynoDave on Jan 31, 2019 8:34:14 GMT -5
In fact, this carb has sight glasses for the bowls, so I think tomorrow I will get a visual on those glasses and see what happens after shutting down. *thumb up* If it's not low, or gone, your long cranking time culprit must be elsewhere. A spacer..... hmmm. Honestly, I don't recall if it has one or now. If not, I'll see about getting one. If the carb is boiling the fuel, an insulating type can help. Just watch your hood clearance. The crossover setup is likely all in place. I think I saw one of the valves on the passenger side exhaust manifold. Do both sides get a valve? Or just one side? Yes, there is a valve in the passenger side manifold. None on the driver side. When the exhaust/engine is cold, a thermostatic spring on the valve closes it, forcing the exhaust gases from the passenger side manifold through the passenger side head, through a passage in the intake that passes under the carb and mechanical choke well. Then out the intake passage into the driver side head, and out that exhaust manifold. Whew! This hot exhaust gas heats the intake when cold, and helps with fuel vaporization, and heats the choke well, causing the choke thermostatic spring to expand and open the choke. As the engine warms, the thermostatic spring on the passenger manifold opens the valve, and normal exhaust flow resumes. In this picture, the center port for the heated crossover in the intake has been plugged with an epoxy. This will keep the intake cooler, allowing for a more dense mixture, and more power. It also keeps the carb cooler. But, it also keeps the choke well cooler, so your choke will be VERY slow to open fully (bad). So switching to an electric choke is recommended with this change (your new carb may already have one). On a Mopar, you can achieve a similar result with new intake gaskets designed for this...they simply block the passage off in the gasket. Of course, now your exhaust has no where to go when that passenger side manifold valve is closed, so you need to modify that to stay open all the time. Details, details. If your engine is original, and never been apart, and of higher mileage, that passage may be blocked anyway (carbon build-up). An infrared thermometer would tell you I should think. If you choose to go this route, I'm sure you can find lots of good instructions online. I was looking at insulating the fuel line. I have some of that woven fiber stuff specifically for that purpose, but it will be difficult to get the line completely covered due to a T used to get the fuel to enter the carb at two different places... although I think I can get most of it covered. If hot fuel is the problem, this will help. *thumb up*
|
|