Motor shakes and has little power under load

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Vali68

Vali68

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My 68 Valiant with a slant 6 3.7 stalled on me yesterday. It took me a minute to get her to fire back up. Once it did start, the motor was very shaky and was running really rough. I was only a mile or so from the house, so I started driving it, but it would only go about 10mph. No power. Pinging like crazy. I know this may be vague, but you true Mopar guys out there may be able to narrow down what I may look at.
 
Throw a timing light on it and see where your at. Maybe pull the dist and ck the plastic gear, Give everything in the dist a good look over. Hopefully you didn't jump a tooth on your timing chain. Is it points or electronic? I've seen the ecu boxes for the electronic do some weird things also.
 
Symptoms sound most like running very lean. Probably starved for fuel. Check for fuel flow by disconnecting the carb inlet and running the tube into a gallon jug. You should see glugs coming out as you crank. BTW, don't smoke. But, it may pump when cranking and stall at higher speeds. Check that the fuel hoses on the suction side are not soft and collapsing (fuel pump inlet, gas tank outlet). If you never changed to modern "fuel injection" hose, today's ethanol may have gotten them. They can even degrade internally and look OK outside.

If all OK, check that the fuel filter and carb inlet isn't plugged (maybe 1st thing), that the inlet needle moves fine. If a Holley 1920, the internal idle metering block can plug, but some here know how to blow it out from below.

Of course, also check for spark and that the distributor didn't somehow become very advanced.
 
Also check in your distributor and make sure both springs are still attached at both ends and unbroken.
 
No sure fire explanation for this, I don't think. It's going to take some investigation on your part.

Good points have been made.
 
timming chain or crack dist cap ,don't use the point dist cap with electronic ign they will crack . or large vacuum leak ,bottom of pcv valve fall off ? good luck
 
grab carb and shake it, is it still solid? I had a truck run like this and the only thing holding the carb on was the vacuum, all 4 bolts were finger loose, like you could see a thread loose. Distributors have a nylon gear on them that can go bad.
 
Was it running OK before this? If so........timing chain or distributor problems.
 
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