Advice Needed - Can't Start Rebuilt 273

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Steve and all...OK, built and installed piston stop....balancer marks are bang on. Stops one way @ 10* after, and back the other way...stops @ 10* before.

dot to dot is when #6 is on compression
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I've tried the dizzy both ways...0* and 180*....I get nothing when it's 180* out. I've actually set the dizzy using my timing light on #1 plug wire while cranking...and the light flashes at 10* advanced...have tried 0* as well....no change. Turn the dizzy too far ahead and it hits against the starter.
 
Val, with #1 at TDC compression, pull the dizzy and where is the slot on the gear pointing? In my 69 factory shop manual, it shows the "slot" pointing to the 1st intake manifold bolt on the drivers side.(pic says for 340) but I think its the same for all sb's??
 
What are the chances that the fuel is poor? Been sitting? Tried any fresh, down the throat, or starting fluid?

HERE's a story. In the 70's a then friend was trying to start a brand new 396, 57 Chev. I KNEW it would run--I helped install the cam and set the prelim valve lash.

He screwed around most of a Sat morn, and finally came and got me. Says "we're priming it with that Pepsi can full of gas"

I sniffed it to make SURE I wasn't gonna pour Pepsi down the carb, and said "go get some gas."

IT WAS JP-5!!!!! (Kerosene to you civilians, LOL)
 
4spdragtop said:
Val, with #1 at TDC compression, pull the dizzy and where is the slot on the gear pointing? In my 69 factory shop manual, it shows the "slot" pointing to the 1st intake manifold bolt on the drivers side.(pic says for 340) but I think its the same for all sb's??
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Actually, Steve, the "slot" doesn't matter so long as the rotor actually points to the no1 plug when the timing marks are on no1 ready to fire.
 
OK so let's review. If I understand what you've done, you've

confirmed the timing marks are actually accurate

Rotated the cam and checked valve cycles, right? So it can't possibly be a mis--ground cam, and the cam drive has to be correct?

Is it possible that you have the distributor one "hole" retarded?

I NEVER set static timing at TDC. Bring the thing up to "coming up" on the timing marks, no1 on the compression stroke, and set the marks WHERE you want timing to be. I'd start with AT LEAST 10-12 BTC, and maybe more, 15 BTC.

Now with your dist in, the rotor pointing to the no1 plug hole, RETARD the timing (rotate dist CW) and then bring it back slowly ADVANCED.

If you have points, use a light/ meter, and slowly advance until points just open

If you have breakerless, set so the reluctor is pretty much centered on the pickup core.

NOW look at the rotor and wiggle the mechanical advance. Mark the dist. housing with a file, marker, whatever, so you know where the center of the no1 plug tower is. The rotor, which "will rotate" CW, should be APPROACHING this no1 plug tower.
 
4spdragtop said:
Val, with #1 at TDC compression, pull the dizzy and where is the slot on the gear pointing? In my 69 factory shop manual, it shows the "slot" pointing to the 1st intake manifold bolt on the drivers side.(pic says for 340) but I think its the same for all sb's??
Click to expand...

Steve....thats where it's pointing.
 
67Dart273 said:
What are the chances that the fuel is poor? Been sitting? Tried any fresh, down the throat, or starting fluid?

HERE's a story. In the 70's a then friend was trying to start a brand new 396, 57 Chev. I KNEW it would run--I helped install the cam and set the prelim valve lash.

He screwed around most of a Sat morn, and finally came and got me. Says "we're priming it with that Pepsi can full of gas"

I sniffed it to make SURE I wasn't gonna pour Pepsi down the carb, and said "go get some gas."

IT WAS JP-5!!!!! (Kerosene to you civilians, LOL)
Click to expand...

Just put in 5 gallons of fresh 91 octane in the tank...haven't tried down the carb as I observed it was getting lots of fuel.

We're gonna do a leak-down test on it tomorrow or the next day to see where the lost compression in #1 and #3 is going. I'm guessing out the intake (carb). The guy who did the heads thinks maybe there's some "foreign matter" holding the intake valves slightly open in those 2 cylinders. We're gonna try and "shock" them to see if we can get'em to seat properly.

I'll keep y'all posted.
 
I had the same problem with the 360 Magnum I installed in my 74. It would start and the shoot a big flame threw the carb. Tried everything. Checked firing order, checked for spark, and even checked if the distributor was aligned correctly. I had a bought a used Edelbrock 750 for the engine. When I received the carb, I rebuilt it. The engine seemed to get plenty of fuel. I could see the carb shooting fuel out of the primaries. It would keep starting and then backfire threw the carb. My son keeper putting out the fire with a towel LOL. My friend said that we had tried everything and checked everything except the carb. He said that to get a squirt bottle and put some gas in it. We removed the carb and poured fuel into the intake. The engine started up and revved up to around 3000 RPMs before quitting. I bought a new Quickfuel 750 carb and tried again. I had my son put the carb on. This is his first car project. He is 15. When we tried again, the engine would start and backfire again!!!!! It turned out that this time my son had mounted the carb on top of flat washers. I didn't notice until I started to remove the carb. The car runs great. I would double check the carb. Hope this helps.
 
4spdragtop said:
Well sounds like you are 100% with the timing....I was really hoping I would make a difference dangit!! :banghead:
Proper distributor?? Ballast resistor??
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Tried 2 different dizzys...one points and one w/Chrysler electronic sytem...no changes

We're jumping from battery "+" to coil, so that removes the ballast resistor ( and the entire key system for that matter)from the equation.
 
It ran so all of the ignition stuff was correct. My guess is a valves sticking in the guides.
In engines where the pistons can hit the valves, how you turn things to install a timing chain could possibly bend some valve stems.

OOPS
Looks like this thread is about 4 years old.
 
advance the ignition timing while turning motor over counter clockwise.. You may have to jump the gear if the vacuum advance hits.
 
advance the ignition timing while turning motor over counter clockwise.
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It hits against the starter if I go too far advaced.


OK guys...update time....

I did a leak-down on the 2 low cylinders...they seem to be leaking into the crankcase, so I guess the rings haven't sealed too well in those cylinders. Should still run though, right?

I reset the valve lash back to specs, plus about 2 or 3 thou. more. Still no change. I'm running out of things to check. I'm going to post a video of whats happening....maybe that will "spark" a few ideas...lol

[ame="http://www.youtube.com/watch?v=RzOaSMrgZCI&feature=youtu.be"]1967 Dart 273 Engine Start - YouTube[/ame]
 
65Val said:
It hits against the starter if I go too far advaced.
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This I don't get. "Hitting against the starter" is caused by compression, fuel, and spark, and too much advance. If it's got "enough" to hit on the starter, then the darn thing SHOULD run.

But what I saw in that video is not hitting the starter. That looks like it's WAY retarded.
 
67Dart273 said:
This I don't get. "Hitting against the starter" is caused by compression, fuel, and spark, and too much advance. If it's got "enough" to hit on the starter, then the darn thing SHOULD run.
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Yes, i agree, but, it won't. I tried advancing it way up (not shown in video...timing in video is 10*BTDC and I advanced it a few during the video) and still won't start, but does hit against the starter. If I have my timing light hooked to #1 and pointing @ the damper, it will flash at 10* advanced on the tab while cranking, so that tells me that the timing is bang-on (factory initial advance is 10*BTDC).
 
Another update...I took the timing cover off the front of the engine to make sure all the marks were lined up, etc. Everything lined up, and the new timing set matched the old stuff I took off the engine, so that eliminated that. I then found the old cam that was in the engine before the rebuild to compare keyway position, etc. Well, after doing a preliminary look-see, it appears that this cam is not ground correctly. When you compare lobe to lobe, cam to cam, most of the lobes on the new cam are nowhere near the old one, so this may be a reverse-rotation cam, or a just-plain F*&%$D up one. We're removing it from the block tomorrow for a side-by-side comparison, and pictures so I can phone the grinder and give them H-E double-hockeysticks!!!!
 
Geez. I had understood you checked the cam against crank degrees. Something someone else mentioned is it might be a 318 poly cam. Hell I didn't know a poly cam would fit the block and operate the valves.

Sounds, though, like you might have found something. If this turns out to be the case, seems like the pistons would be hittin somewhere.
 
This sucks, sorry I aint much help. I watched the video and it sure seems/sounds like timing to me. Im with you in thinking the cam is buggered!!
Anyone chime in here about the bronze drive bushing being oriented correctly?? I know what the 69 FSM says, but I know the FSM threw me a curve ball with the timing...
I hate to say it but I hope its the cam or we look like "dumbass's" LOL
 
Well at least you finally have your answer and know you "ain't" goin' nuts. I'd be havin one HELL of a conversation with that cam grinder!!!!
 
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