Hey all, I have a 72' Skylark and it just won't drive. The car ran fine for a few months after I bought it, but recently conked out. The engine takes a lot of cranking to get started, and once it does it won't hold an idle and dies once it is put into drive. I have recently replaced the battery, plugs, voltage regulator, and alternator. I also checked the firing order and timing and have found no problems- besides I never messed with them from when it ran OK. All suggestions are welcome, I hate to see my car like this.
You need to find out if it is ignition related or fuel related. If the fuel pump is on it's way out, the fuel level in the carburetor will be low, and it won't idle. If the points are on their way out, the spark will be very weak and the plugs will foul.
Thanks for replying! The fuel problem is actually looking like a likely solution. From what I understand you can hear whether or not its working, but would this apply to my car?
I had just realized how dumb my previous post was and was going to edit it just now, but you beat me to it! Anyways I'm pretty sure this is the problem- the car takes a lot of cranking and can't hold an idle, that means not enough fuel, right? Also, would backfiring be symptomatic of a bad pump? If so, I think we have a winner.
Not necessarily. It could be a bad set of points too. When you say it backfires, does it backfire through the carburetor? If it does, that indicates a lean condition. When was the last time the engine was tuned up? Points, condenser, distributor cap, ignition wires, and spark plugs? Have you checked point dwell?
I actually had an electrician friend of mine take a look at the distributor cap and whatnot a while back and he found nothing wrong with it. That was back when I thought the alternator was the problem.
You can use a small funnel and fill the fuel bowl through the carburetor vent. It won't take much. Then start the engine. If it idles and runs better, either the pump is not keeping the carb full, the filter is clogged, or there is an internal problem with the carburetor. It could still be ignition related though.
I wonder if maybe he backfired a vacuum cap off. Ive seen that. Engine backfires and then it has a massive vacuum leak and wont idle!
I had a fuel pump come loose from it's mounting and the car acted up just before it wouldn't start. One bolt was missing, and the other one was backing out. ElectraJim
once you get it started ...does it run at higher rpm ? sounds more like a jumped timing chain...has the motor ever been rebuilt ??
bad fuel pump should at least idle and then run out as it revs.....just plain old crappy idle it could be a whole host of things .....vac leak, bad carb, bad distributor, bad timing chain, burnt valve, a few others. Have you checked the plugs ? what do they look like ? could even be too rich. does it run better if you advance the timing ALOT ?
KISS Keep it Simple S______ Anyway, check the oil dip stick, see if its over full(allowing you maintain it) and to see if the oil has an odor consistent with fuel/gasoline. This can happen when the diaphram in the fuel pump goes and fuel leaks into the crankcase, and long term, thins/dilutes the oil, washing out the bearings, followed by catastrophic engine failure. Look at the point gap/dwell. Or, find someone you trust or who trusts you, pull the coil wire while the trustee cranks the engine while you hold the coil wire(the end going into the top of the dist cap) an inch or so away from a bolt/ground. See if the spark that jumps the gap is blue/white. With the engine off, look at the contact points surface(pitts or dirt, or mal-aligned points) may need to be replaced and re-gapped. Been a while since I seen a dwell meter, points are almost a lost are, but so are Buicks and carbs. Get it running, use WD-40, spray around the base of the carb and see if the idle speed changes(locating vacuum leaks) another way is to see if the idle changes by closing the choke or placing your hand over the carb opening(close to the top will work). Another thing to look at, is the rubber fuel line sections that run from the frame to the fuel pump and from the gas tank to the fuel lines over the rear end. If any of them are dry & cracked they could be leaking enough vacuum to make the fuel pump insufficient. Good Luck! Merry Christmas
