Joined: Mon Oct 10 2005, 10:04PM
Location: Glendale Heights, IL
Posts: 116
Been unable to get the Newport started since last fall when I went to winterize it.
Seems to be a fuel delivery issue. Car will start if I prime with some gas down the carb, but dies as soon as that is gone.
Started troubleshooting on Friday, replaced fuel filter, still no go. Disconnected fuel line from carb and ran an extension tube into a gas can and then cranked the engine. Could not get any gas to come out line after cranking for a while.
I'm thinking next step is replace fuel pump, but wanted to run it by the board to see if I'm missing something. Tank is about 3/4 full, added a few new gallons a couple weeks ago since I started trying to get it started.
Car/Engine details: 1968 Chrysler Newport convertible, 383 rebuilt about 12 years ago to magnum specs. Car has stock 4bbl manifold with Edelbrock 600 electric choke carb. Upgraded to electronic ignition, orange box.
Until last summer, never had a problem getting it started. Late in the summer started having hard starting issues, but was always to get it going after a little gas in the carb.
I don't drive it more than 200 miles per year, so far this year still at 0...
What do you all think? Fuel pump next and if no better, then drop the tank and see what's going on in there?
Joined: Sat Aug 19 2006, 05:03PM
Location: Ontario, Canada
Posts: 2919
I agree with John, but since you've disconnected the line from the tank and put it in a jerry can and still can't get fuel to the carb, it's probably fuel pump or pushrod IMO.
Mechanical fuel pump is a diaphragm with checkvalves on the inlet and outlet sides. Failure could be torn diaphragm and/or leaking checkvalve. If the diaphragm has failed, your crankcase oil may be contaminated with fuel and should be changed as well.
You should be able to blow air into the inlet side of the pump but if you suck on it there should be a vacuum. If you plug the outlet side while blowing into the inlet side, it should build pressure (not leak past the diaphragm and out the back). On the outlet side, you should be able to suck air from it, but if you blow into it, it should build pressure. If your pump passes those tests it's probably good (or good enough) and the problem is worn pushrod.
If the pushrod is worn, the metal shavings have gone into the crankcase oil. If so, I recommend changing the oil and filter as a precaution. All big blocks use the same fuel pump pushrod. There is not a different length for 383 versus 440. The rod rides on a lobe on the camshaft. If replacing the pushrod, slather it in moly break-in lube as you would the lifters when installing a new cam.
I went through this same exercise myself. Car left me stranded 4 years ago. Changed pump and filter and it lasted the rest of the summer. Then it did the same thing the next summer and I figured out it was the pushrod. The fresh pump and filter probably made-up for the shorter stroke from the worn pushrod until it ground down to the point that it was hardly working the pump.
Joined: Mon Oct 10 2005, 10:04PM
Location: Glendale Heights, IL
Posts: 116
Finally got the car in the shop where I work now. Replaced both the pump and the pushrod with the Airtex models Mike recommended. Works like a dream. Compared the old pushrod to the new and the old one was ground down at least 1/4". Changed the oil and filter also before starting.
Fired right up after the normal 20-30 seconds of cold cranking with a dry fuel line. Ran really well for not having been run in about 10 months.
Will resume my normal summer pleasure cruising now, not much of summer left...
Thanks again for your diagnosis, it saved a lot of guessing!