"68 Fury III. 318 with Carter carb. Runs rough.

[Lord Alvin]

I'm no mechanic so I have had this car worked on by three different shops here in Nashville. All three are very reputable. One of them specializes in older Mopars. The car idles a little rough and it hesitates when you step on the gas or go around a corner. Not usually enough to kill it, but just enough to be really annoying. The car tends to knock when accelerating. I had the original carb rebuilt twice and bought a matching remanufactured carb and had it installed. Same problem. My gas tank and fuel lines are clean. I only use non-ethanol gas in the car with a lead substitute. The car has 83,000 original miles on it and has always been well cared for. I am getting the feeling that I am going to have to figure this one out on my own. Where do I start?

 

[Big blubber]

Might be an ignition problem or the choke might not be returning properly giving it to much gas and then it dies check the simple things first

 

[commando1]

Where do I start?

I say back at the carb.
Today's reman carbs are crap and the rebuild kits don't solve every problem.
Since you have a 2 bbl, you're kind of screwed in the replacement category.
The "tends to knock" has to be solved first.
That one is not rocket science.
Timing, timing, timing. Once that has been 100% ascertained and it still knocks, we'll take it from there.
Don't let the testosterone boys start jumping nine steps ahead.

 

[Lord Alvin]

Might be an ignition problem or the choke might not be returning properly giving it to much gas and then it dies check the simple things first

Thank you for the advice. Now how might I go about doing those things? Is there a book or a website or some kind of online tutorial? I know the basics of how an engine works and how a carb works, but I don't know how to trouble shoot these things.

As far as ignition goes, I know I'm getting spark. I don't know how hot the spark is. It's not missing. The plug are new. The timing looks right according to the timing light. My plug wires are old. I don't know about the condenser. Distributor cap is new and the points are good.

The choke is fussy on this car. The car doesn't smoke at all, but the exhaust does smell strongly of fuel. Would that mean I'm running too rich? How can I test this? Is this a possible vacuum leak?

 

[Lord Alvin]

I say back at the carb.
Today's reman carbs are crap and the rebuild kits don't solve every problem.
Since you have a 2 bbl, you're kind of screwed in the replacement category.
The "tends to knock" has to be solved first.
That one is not rocket science.
Timing, timing, timing. Once that has been 100% ascertained and it still knocks, we'll take it from there.
Don't let the testosterone boys start jumping nine steps ahead.

According to my normal mechanic, the timing is spot on. I have heard that there are better ways to set the timing on these cars, but again, I'm not a mechanic. Just a frustrated owner. How do I do this so that I am sure that the timing is correct?

 

[commando1]

Worn timing chain can make setting the timing to the exact original OEM specs not the solution.
Keep retarding the timing a degree or so at a time until it stops knocking and see how it the runs overall.
If the knock does not go away before the engine starts running adversely from too much retardation then we go to step 2.

That's how I was taught to Troubleshoot and it always worked for me.

 

[Lord Alvin]

I have a rather simple question. How in the Hell do you reach the bolt for the distributor hold down clamp with a wrench? Am I doing this wrong or just stupid? I cannot find any angle that works.

 

[commando1]

Ratchet, socket extension, flex socket.

 

[Lord Alvin]

Thanks. I don't have a flex socket. Oh well. At least I get to buy tools.

 

[Big blubber]

I would try what Commando says ,Stan knows his stuff also try the tech forum plenty other guys will chuck there 2 bobs worth in nothing worse than your motor acting up it's frustrating hope you get it fixed and your back on the road . Ps" if the exhaust is real sooty it's between the carb and ignition over fulling

 

[Big blubber]

I knew a guy who had a 69 300 And he had a similar prob ,ended up it was a stretched timing Chain causing ignition problems could be this

 

[mr. fix it]

here is a trick I used to do with some cars that were not happy with stock timing specs.
Using a vacuum gauge worked like a charm.

This site goes on to explain some of the reasons why the engine will not run right.

http://classicinlines.com/vacuum.asp

 

[Lord Alvin]

Thanks for all of the help everyone. I stopped by a friends shop on the way in to work today and got the timing sorted out. It is good now. It is still knocking and pinging a little on inclines. What next?

 

[commando1]

High test.

And how's the bog?

 

[Lord Alvin]

High test.

And that is? Remember, I am not a mechanic.

 

[commando1]

And that is? Remember, I am not a mechanic.

Wow. You must be very young.

Fill it up with high test...

High octane gas.
Premium.
Ethyl....

 

[Lord Alvin]

I have only ever put premium, non-ethanol gas in the car. I'm 46. I just don't work on cars much. I'm sure if you walked into an AES meeting with all of my audio engineer buddies in Nashville you wouldn't understand half of what we were talking about. Old cars just aren't my specialty.

 

[commando1]

I have only ever put premium, non-ethanol gas in the car.

And the bog?

 

[68plymouth383]

I can't imagine a small block needing to run premium gas because it pings......

 

[commando1]

I can't imagine a small block needing to run premium gas because it pings......

I agree but the engine is probably tired at this point, the timing chain stretched, the heads a little carboned up...
It can go on and on.
Alvin is not a mechanic and I'm trying to keep it down to basics for him to try first before going to headier stuff.