slant 6 troubles

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SkiP!

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my 69 dart custom (225 /6) just had new timing chain, gears, gaskets, set the timing and adjusted the valves, harmonic balancer, valve springs, valve guides and seats, cam and lifters, carb rebuild, new distributor, and exhaust manifold and im $2,300 in debt with a car that still pops out of the carb...what the hell is wrong with this thing?! theres almost nothing left to replace except the block itself...please help...:mumum:
 
where did you set the timing?
Backfire through the carb is usually caused by retarded timing or a lean condition. Is there a good shot of gas from the accel pump in the carb?
Whan I had the/6 in my car, the factory timing spec was like TDC or maybe 2 degrees ATDC, but I set it at 5 before and never had any problems. Just some thoughts, and don't give up on 'er!
 
*sigh*i dont really know...im pretty sure my mechanic said it was TDC, and yeah u can kinda see a mist of gas come out of the carb but not always...i know when he unplugs #6 it stops popping, but it runs rough of course...
 
Sounds like the possibility of a flat exhaust lobe. Pull the valve cover and check the valve action on #6. Your mechanic does know that a '74 /6 has mechanical lifters right? Valve adjustment problem?


Chuck
 
Did it break or slip the timing chain before this work was done? I am not sure if this is an interference type motor or not, but if the chain slipped or broke, one or two of the valves may be bent if the piston was able to reach the valve/s. Could also be a burnt valve. This is all only true if the valves had no work done to them. Just a thought.
 
First off, it's not the block. Nor is it likely to be an exhaust lobe. Intake valve perhaps, exhaust no.

What is you vacuum reading at idle, and is it steady? Is it crosswired? 1-5-3-6-2-4 Plug wires and distributor cap new? It would be unfortunate if you had spent all of this money only to discover that a $5 distributor cap was your problem.

I'm sorry, but if your mechanic has done what sounds like a complete valve job on a slant 6 and it still isn't running right, HE IS A DUMBA$$. Take it somewhere else, and sue the bastard out of business.
 
Chief, ever seen a motor run with a bad exhaust lobe? It pops out the carb when it happens. The pressure in the cylinder has to go somewhere and if it can't go out the exhaust because the exhaust valve won't open it goes out the intake valve which opens right after the exhaust closes or at least is supposed to close. Seen it plenty of times and just replaced a camshaft in and '85 Jeep Cherokee last month because of this same problem, flat exhaust lobe, popping back thru the carb. I can't say for sure that this is her problem because I am not there but popping back thru the intake and carb are symptom of a flat exhaust lobe.

Chuck
 
OK I can see that I suppose. About 7 seconds with a vacuum gauge will tell the tale. Steady vacuum = ignition problem. Pulsing vacuum = mechanical defect.
 
I'm thinking it's a lash problem. Maybe an intake too tight by a hair? In any case, I support the "find a new technician". You replace what's not good. You dont replace until it gets good. If he can't tell what's good before he replaces, find someone who can.
 
moper said:
I'm thinking it's a lash problem. Maybe an intake too tight by a hair? In any case, I support the "find a new technician". You replace what's not good. You dont replace until it gets good. If he can't tell what's good before he replaces, find someone who can.
Click to expand...

I believe (and & I am taking a guess here) that the person working on the car is from her place of business and perhaps she doesn't want to offend this person by pulling the car (especially, if some of the work might be discounted). Just taking a guess.
 
Some of my friends own machine shops. They're good guys, but I wouldnt let them machine anything for me. Sometimes it's even easier on a friendship than letting them help...lol.
 
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