Beyond Frustrated - Wont start/stay running

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I don't know sh** from shinola but.....do you know the condition of the timing chain?

I rebuilt my 225 and got it running last fall. Everything is new. I got a new Cloyes timing chain and was VERY disappointed. I could not believe how much slack was in this new brand name chain set. I can't imagine how much worse it would get after 20,000 miles or so. I did some research and bought a Rolmaster set from a place in CA. (What the Valiant needs, the Valiant gets)

Man, what a difference in quality, practically undetectable back lash. And it's setup with multiple keyways though I did mine straight up. My now 2 week old grandson will be driving this car in 50 years with the same timing set.

Sounds from what you're saying that it could be spark scatter.
 
backin the old days, late 80's to bot late 90's, I had the $$$$ to buy cars worth restoring right, so the engines all went to the machine shop. I would try to start/run them with the old dist. and /or carbs, after a while, this I finally got smart,(sorta), and had a rebuilt AVS or new Edelbrock,.. and a new fresh dist. , and usually changed that 68-70 roadrunner, or charger, or superbee over to electronic ign. also bought a new under hood wiring (NO not from yearone).., and did what people now call the MADD conversion.... never any problems after that.
not saying that will cure your problem, but.....
 
The good news really good news; that is great progress. The added sputtering can make sense; sometimes you fix one thing and it makes something else stand out more; you just have to slog through all the fixes.

So, is this timing really jumping that much when it sputters? That would explain some of the issues like the idle changes. That is certainly a problem. I think I would be taking the distributor apart (again) and seeing what is loose/worn/disconnected on the top side, under the breaker plate. I'd be suspecting the mechanical advance, weights, and springs; something may be stuck and then letting go for a moment, and pushing the timing way up. Also, worn shaft bushings can be doing the same; it does not take a lot of sideways movement on the points to really move the timing around a bunch. Or the vacuum advance arm binding....

Also, look at where your vacuum port hose is connected and make sure it is on the timed vacuum port, not seeing manifold vacuum. It ought to have 0 or near 0 vacuum at idle.

As far as the timing chain, I won't say never for this much timing jump, but 15 degrees of timing jump would also be a LOT of cam timing jump. A chain will be badly worn if you have 4-5 degrees of timing change. 15 degrees is about a whole tooth's worth of timing change, so it seems unlikely to me to be the chain. Buuuuut I can't say it is impossible.

And this can also be in the carb but I'd keep looking at that distributor for a while since you have some serious timing jumps going on.
 
This sounds like a misfire. Put the palm of your hand over the tailpipe, not in an attempt to seal it but rather just to feel the exhaust coming out. Now my question is; do you ever feel something like the pipe sucking your palm onto it, however briefly. Try to correlate that feeling to the sputter.
If you experience this, you will need to reset the valve lash, and then follow with a compression test.

Next, It sounds to me like the timing lite is picking up a crossfire, either between two wires or possibly inside the D. Put the lite on #6 and see what it is doing.

Next, make sure the vacuum advance can is getting signal from the Sparkport. At idle, it's vacuum supply should be zero.The idle-timing is always set without the Vcan, and the Vcan should not deliver any timing changes until actually put into gear and lightly accelerating.

Next, make marks on the balancer for 20* and for 30*. Make the marks different from each other. They don't have to be supremely accurate. Just rotate the balancer clockwise to 10* ATC, and make a mark on it next to TDC and another next to 10*BTC.
Make sure the coil is installed with the correct polarity. If it has a noise suppressor on it, remove it.
Now, defeat the Vcan, and start her up.Watch the advance marks as you slowly bring the rpm up to 3000rpm.The timing should move slowly and smoothly to a maximum and back.If you get a lot of "noise", try it on #6

If #6 is also noisy, then you have a problem.
And if the "noise" increases with rpm, you may have a rotor phasing issue.

I would have thought the miss was a vacuum leak, but at your vacuum reading, probably not.
However, when you set the timing to 15* at idle, you had to reduce the idle quite a bit. The transfers may not be delivering very much fuel. So in an effort to keep it idling, you may have given her a lot of fuel at the mixture screws. If this sounds about right, you may have to reduce the idle-timing to get the transfers back on line; and to back out the mixture screws. The goal is to have the mixture screws at about 1.5 to 2.0 turns out .
However, if you set the idle timing with the Vcan fully engaged,runing on manifold vacuum, then firstly, the transfers are waaay out of sync, and secondly, the base timing will be waaay retarded.So, anytime the manifold vacuum drops, and the timing reverts to mechanical, the presto! there's your retard.
 
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Yea after talking about this and thinking about this it does sound more like a distributor issue than a carb. However there could still be an issue with the carb. But as stated above, fix one issue at a time... The hose for the vacuum advance is not on the manifold, it is on a port on the carb. However as I am sitting here at work, I cant not picture if it is above the throttle plates or not... I believe that is what dictates whether or not the vacuum advance sees vacuum at idle or not? and as I think about it more, it doesnt seem to be chain. I feel if it was the chain the sputter should be more consistent than it is.

AJ,
You always have these wild and simple tests haha. I never did put my hand over the tail pipe as it is sputtering. I would say it is not sucking but blowing. But again I never actually put my hand over the tail pipe to verify, so I will give this a try (wont be until after carlisle). I will try to run the other test you suggested as well.
 
If you want to do the tail pipe test right..... hold a newer, stiff dollar bill on one half and move the other half over the tailpipe from the side, with the plane of the bill perpendicular to the pipe end and <1" away. If the exhaust sucks it back into the pipe part of the time, then that generally indicates an exhaust valve problem: burned or worn valve or seat, bad or sticking guide, open lash. Your dollar bill may get dirty LOL

The timed vacuum port can be anywhere on a carb in general. The actual pickup is up in the middle, in the throat above the throttle plates, but it can route through vertical passages in the carb to a tube down lower or up higher. Put a vacuum gauge on it at idle, or find some documentation, and you will know for sure.
 
Well today I got some fabulous news! it is finally running properly!! so good in fact, that it was never this smooth before.

Seeing that I replaced everything in the ignition system since this whole thing started, my vacuum readings didnt fluctuate, and the carb was pulling fuel after I replaced the distributor gear, and the timing was jumping still, it had to be something with in the distributor. So while I was at Carlisle there was a guy selling rebuilt distributors. He had a lot there and a few for slant sixes. So the one I picked up was for a 68 Dart. Last night I got some time and installed it. Needless to say (after screwing with timing and all) it runs flawlessly!!

Thank you everyone for your help and patience in getting me through this!

By the way, the guy I got the distributor from was Pete's Classic Car Parts, Ebay store: Antique vintage parts, ebay name: classic50ply. Really nice guy and gave me a good deal on the distributor to boot!
 
Awesome! I have been working long hours all week so just saw this. Glad you got it nailed.

BTW, hang on to the old distributor. I bet you can take it apart and see what is causing the timing jumps. It could be worn shaft bushings or the plates hanging up and not moving smoothly due to old grease. Often you can rework these and have a good spare.

BTW, did you ever do the dollar bill test on the exhaust? It works to find bad/sticking exhaust valves...... and is always good to make people wonder what the h*** you are doing back there... LOL
 
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No I didnt get a chance to do the dollar bill test. I can try and do that the next coming days. Really havent had much time with everything else going on.

Now I am just trying to enjoy it as much as possible before winter weather in pittsburgh comes in the next few short months
 
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