1970 383 in 1969 Charger Not Running Right

[Road Grabber]

Thanks! No, I need to change the antifreeze for sure! It can overheat, but it runs at 160 degrees unless I'm in traffic for too long, as I have the wrong radiator (from a 1070 C Body that was installed before we bought the car in 1996). I have a temp gauge hooked up (not the factory one) under the dash, and it hasn't overheated excpet one time when I was caught in traffic. It got up to about 220 for about 5 minutes. Other than that, it stays at 160 degrees.

Also, the carb was rebuilt and then tuned by a local carb expert. We also checked the float levels and they are spot on. It just trickles out. I definitely have brake problems. Dr. Diff diagnosed my brake issues through pics I sent him and my car has the wrong brake booster, and non-Charger parts on it unfortunately. I have power front discs and rear drums, but it's a cobbled together mess.

Thanks again for the help!

1. Did you plug the vacuum line going to the brake booster to rule it out? You said it was a mess.

2. When was the last time this engine ran without the issues? If it ran previously without this issue you can at least say it's PROBABLY not a mechanical issue.

3. You mentioned having a stock cam installed. You may need to verify if not now but later if nothing else works if the cam has skipped a tooth or was not installed properly.

4. Does your rotor under the cap point to the correct position when at TDC? The engine could still run but not necessarily well if the distributor gear is in the correct position. If you remove the distributor you can look down the engine. At TDC the distributor gear slot the distributor fits into should be pointing straight forward. Even if the engine runs that needs to be in its' correct position if you want to do things right. Even engine builders make mistakes or don't know Mopars well enough to install them right because many of them do mostly Chevy engines.

5. If you haven't already you should verify there is not a lean condition like suggested before. Start the engine and while running and begin cover the top of the carb (or close the choke a bit) and note what is the reaction of the motor. Does it bog/want to stall? - Meaning too rich to run. OR Does it pick up speed - meaning the engine is starving for fuel and is lean.

6. Pull the plugs and look at them. Spark plugs tell you everything going on inside the engine. Take pictures and post if possible. Keep your spark plugs in order the way they come out.
Are they black?-too rich.
Tan? - good fuel ration
White - Too lean running hot
OR do they look brand new - that cylinder is not firing
What does the exhaust pipe look like? Black? covered with soot? Tan?
Can you feel popping and misfires at the exhaust? Which bank/side? One or both?

You have replaced a lot of parts new but you need to rule out systems or parts of systems to narrow this down. Pump, carb, new fuel, lines etc.
BUT you have said the wiring harness(es) are a mess. It is steering more and more towards an electrical issue if that's the case after ruling other things out.

***7. If you want to completely rule out the engine wiring harnesses and eliminate other issues,

Get a point distributor. (You should be able to get a used one or buy one. You bought everything under to sun anyway and it's good to have around)

- make sure it is a correct one for 383
- install NEW points, condenser, cap and rotor
- remove/disconnect the engine wire harness for a test
- Make sure you are aware of the rotor position and don't install the point distributor 180 degrees out - you verified the cam gear slot right pointing forward at TDC?
- hook up the point distributor to the negative side of the coil
- make a jumper wire to connect from the positive side of the battery to the positive side of the coil. Make the connection at the battery easy to pull off but a good connection
- start the engine
- IF it runs well you have ELECTRICAL issues
- Don't let it run tool long with the jumper. To make it stall just pull the wire from the positive battery as it will harm the coil over time without a ballast resistor.

***This will eliminate ALL of the worn out/possibly melted somewhere or fused wiring somewhere under the dash, or in the wiring harness. It will also eliminate the possible wiring issue you may have with your electronic ignition components.

If the engine runs well with the point ignition system at least now you know it is NOT fuel, NOT a vacuum leak, NOT a mechanical issue BUT IS an electrical issue that now can be troubleshooted. It could also suggest a possible distributor problem.

This will allow you to concentrate on just one area instead of chasing everything around from all directions.

If you STILL have issues you can still use the point distributor if you like if you adapt the wiring. It's pretty easy to convert back temporarily or leave it....

MY TWO CENTS _ Have at it and report back!

 

[Some Car Guy]

Thanks! No, I need to change the antifreeze for sure! It can overheat, but it runs at 160 degrees unless I'm in traffic for too long, as I have the wrong radiator (from a 1070 C Body that was installed before we bought the car in 1996). I have a temp gauge hooked up (not the factory one) under the dash, and it hasn't overheated excpet one time when I was caught in traffic. It got up to about 220 for about 5 minutes. Other than that, it stays at 160 degrees.

Also, the carb was rebuilt and then tuned by a local carb expert. We also checked the float levels and they are spot on. It just trickles out. I definitely have brake problems. Dr. Diff diagnosed my brake issues through pics I sent him and my car has the wrong brake booster, and non-Charger parts on it unfortunately. I have power front discs and rear drums, but it's a cobbled together mess.

Thanks again for the help!

Personally I wouldn’t run a 160. The engine needs to get warm enough to swell the parts fully and not cause wear. They came oem with a 195. I’ve had todays fuels boil with an 195 in due to extra underhood heat. 180 seems to be a happy medium.

Even without a shroud, they shouldn’t heat up if sitting still if the system is set up well. I had a 383 road runner that had a 26 radiator in a 22 hole that had no shroud. It sat right in the 195 stat on a mechanical gauge.

A c body radiator isn’t a problem. The fact that it sounds plugged up does.

 

[Sixpactogo]

I may have missed it since I didn't read every response but I am wondering about the fuel sock in the tank. Just because you are getting clean gas to the carb, doesn't mean the sock is not plugged up with 50 + years of rust and gunk. It seems like you have tried a ton of things but it does sound fuel related to me and something to verify. It was mentioned that the ECU can cause issues when warmed up so another thing I would check would be to verify a good case ground on the ECU. Many things can cause intermittent problems but persistence usually pays off.

 

[glrestomod]

1. Did you plug the vacuum line going to the brake booster to rule it out? You said it was a mess.

2. When was the last time this engine ran without the issues? If it ran previously without this issue you can at least say it's PROBABLY not a mechanical issue.

3. You mentioned having a stock cam installed. You may need to verify if not now but later if nothing else works if the cam has skipped a tooth or was not installed properly.

4. Does your rotor under the cap point to the correct position when at TDC? The engine could still run but not necessarily well if the distributor gear is in the correct position. If you remove the distributor you can look down the engine. At TDC the distributor gear slot the distributor fits into should be pointing straight forward. Even if the engine runs that needs to be in its' correct position if you want to do things right. Even engine builders make mistakes or don't know Mopars well enough to install them right because many of them do mostly Chevy engines.

5. If you haven't already you should verify there is not a lean condition like suggested before. Start the engine and while running and begin cover the top of the carb (or close the choke a bit) and note what is the reaction of the motor. Does it bog/want to stall? - Meaning too rich to run. OR Does it pick up speed - meaning the engine is starving for fuel and is lean.

6. Pull the plugs and look at them. Spark plugs tell you everything going on inside the engine. Take pictures and post if possible. Keep your spark plugs in order the way they come out.
Are they black?-too rich.
Tan? - good fuel ration
White - Too lean running hot
OR do they look brand new - that cylinder is not firing
What does the exhaust pipe look like? Black? covered with soot? Tan?
Can you feel popping and misfires at the exhaust? Which bank/side? One or both?

You have replaced a lot of parts new but you need to rule out systems or parts of systems to narrow this down. Pump, carb, new fuel, lines etc.
BUT you have said the wiring harness(es) are a mess. It is steering more and more towards an electrical issue if that's the case after ruling other things out.

***7. If you want to completely rule out the engine wiring harnesses and eliminate other issues,

Get a point distributor. (You should be able to get a used one or buy one. You bought everything under to sun anyway and it's good to have around)

- make sure it is a correct one for 383
- install NEW points, condenser, cap and rotor
- remove/disconnect the engine wire harness for a test
- Make sure you are aware of the rotor position and don't install the point distributor 180 degrees out - you verified the cam gear slot right pointing forward at TDC?
- hook up the point distributor to the negative side of the coil
- make a jumper wire to connect from the positive side of the battery to the positive side of the coil. Make the connection at the battery easy to pull off but a good connection
- start the engine
- IF it runs well you have ELECTRICAL issues
- Don't let it run tool long with the jumper. To make it stall just pull the wire from the positive battery as it will harm the coil over time without a ballast resistor.

***This will eliminate ALL of the worn out/possibly melted somewhere or fused wiring somewhere under the dash, or in the wiring harness. It will also eliminate the possible wiring issue you may have with your electronic ignition components.

If the engine runs well with the point ignition system at least now you know it is NOT fuel, NOT a vacuum leak, NOT a mechanical issue BUT IS an electrical issue that now can be troubleshooted. It could also suggest a possible distributor problem.

This will allow you to concentrate on just one area instead of chasing everything around from all directions.

If you STILL have issues you can still use the point distributor if you like if you adapt the wiring. It's pretty easy to convert back temporarily or leave it....

MY TWO CENTS _ Have at it and report back!

Will do! I just printed all this out, that way I can get to all of it once I'm free and bale to (hopefully this weekend)! Thanks so much!

 

[glrestomod]

I may have missed it since I didn't read every response but I am wondering about the fuel sock in the tank. Just because you are getting clean gas to the carb, doesn't mean the sock is not plugged up with 50 + years of rust and gunk. It seems like you have tried a ton of things but it does sound fuel related to me and something to verify. It was mentioned that the ECU can cause issues when warmed up so another thing I would check would be to verify a good case ground on the ECU. Many things can cause intermittent problems but persistence usually pays off.

Someone did mention the sock, definitely going to check it out! Also, will check the ECU, thanks so much for the help!

 

[glrestomod]

Personally I wouldn’t run a 160. The engine needs to get warm enough to swell the parts fully and not cause wear. They came oem with a 195. I’ve had todays fuels boil with an 195 in due to extra underhood heat. 180 seems to be a happy medium.

Even without a shroud, they shouldn’t heat up if sitting still if the system is set up well. I had a 383 road runner that had a 26 radiator in a 22 hole that had no shroud. It sat right in the 195 stat on a mechanical gauge.

A c body radiator isn’t a problem. The fact that it sounds plugged up does.

Thanks! I'll definitely check out the situation with the radiator! Good to know, I appreciate the help!

 

[Road Grabber]

Someone did mention the sock, definitely going to check it out! Also, will check the ECU, thanks so much for the help!

Be careful under the car removing the sender!! Make sure you siphoned the gas. You could look at the condition of the gas at that time.

DO NOT PUT A DROP LIGHT WITH YOU NEAR THAT TANK WHEN YOU REMOVE THE SENDER OR WE MAY NEVER HEAR BACK FROM YOU AGAIN.

 

[glrestomod]

Be careful under the car removing the sender!! Make sure you siphoned the gas. You could look at the condition of the gas at that time.

DO NOT PUT A DROP LIGHT WITH YOU NEAR THAT TANK WHEN YOU REMOVE THE SENDER OR WE MAY NEVER HEAR BACK FROM YOU AGAIN.

Thanks, definitely helpful!

 

[Some Car Guy]

You could just blow the sock off with an air hose. Disconnect the fuel line, use one of those blow nozzles with the rubber tip. Few good shots should blow that thing off. It won’t hurt to have it at the bottom of the tank.

You can look in the filler tube with a flashlight and see if it blew off.

As long as you have a filter in the line before the pump I’d be unconcerned as to doing this. Will save a lot of time to get skip getting the sender out.

 

[Sixpactogo]

You could just blow the sock off with an air hose. Disconnect the fuel line, use one of those blow nozzles with the rubber tip. Few good shots should blow that thing off. It won’t hurt to have it at the bottom of the tank.

You can look in the filler tube with a flashlight and see if it blew off.

As long as you have a filter in the line before the pump I’d be unconcerned as to doing this. Will save a lot of time to get skip getting the sender out.

Wow! You're kidding, right?

 

[Some Car Guy]

Wow! You're kidding, right?

No, you’ve never heard of doing that? Wow.

 

[Road Grabber]

The original socks can be pretty tough to remove.
Removing the sock won’t protect the fuel pump….
To each his own.

 

[Some Car Guy]

The original socks can be pretty tough to remove.
Removing the sock won’t protect the fuel pump….
To each his own.

They can be. It’s not a guarantee to get it off. Hence looking to see if it worked.

I mentioned the need for a filter for a reason. It won’t be any worse than a sock and no filter.

 

[RemCharger]

^^^^ and the filter will tell you if there's any reason to go in and replace the sock. And / or clean the tank out

 

[Sixpactogo]

Wow! You're kidding, right?

Yeah, I've heard of that. You must be related to my neighbor. He uses the twist lock electrical connectors under his dash too. Why fix the problem when you can skirt the issue and hope it heals itself. Guys like you are the reason I like to do my own maintenance.

 

[Road Grabber]

They can be. It’s not a guarantee to get it off. Hence looking to see if it worked.

I mentioned the need for a filter for a reason. It won’t be any worse than a sock and no filter.

I’m not challenging the idea. Just interested in how someone would do this. The metal fuel line leaves a short area to hook up the sender at the tank and it runs pretty close to the fuel pump inlet hookup under the hood along the frame.
That would mean placing a filter just outside the tank or between the frame under the hood and the bottom of the pump. Not very protected.
The fuel line under the hood has about an 8” rubber section connecting the line to the pump that moves when the engine revs.

Where would you put the filter before the pump?

 

[Some Car Guy]

I’m not challenging the idea. Just interested in how someone would do this. The metal fuel line leaves a short area to hook up the sender at the tank and it runs pretty close to the fuel pump inlet hookup under the hood along the frame.
That would mean placing a filter just outside the tank or between the frame under the hood and the bottom of the pump. Not very protected.
The fuel line under the hood has about an 8” rubber section connecting the line to the pump that moves when the engine revs.

Where would you put the filter before the pump?

I’ve seen and had these cars with a filter right before the pump. Like your saying, there is like 8” there you could splice in a filter. I don’t know if you could when the car had a vapor separator. I’d have to study mine and see. First one I’ve had is my current car.

 

[71Beeper]

Fuel filter before the pump.

 

[Road Grabber]

Interesting. Never saw that.

Someone did mention hooking up a test tank to rule out the fuel tank and lines before. I’m still leaning towards electrical. Fuel starvation is a possibility.

In marine boat troubleshooting you place a section of clear hose to see what’s going on. That could be a simpler solution to test starvation and see if there is fuel percolating.

Replace the fuel line with clear hose temporarily to the pump for the test with clear tube. Faster, cheaper and easy to access.

What made you decide to put that filter there?

 

[71Beeper]

Road Grabber - I put the filter there as it is easy accessible as well as catching anything before it hits the fuel pump.
Filters like that shouldn't have any restriction in fuel flow.