91 ford E350 460 auto trans…beat up ranch vehicle, muffler pretty much disconnected, running like that for well over a year. In the last couple weeks it would “skip” (misfire) a little once in a while when cold. (plugs probably, right?)
Son was taking it to work the other day. Started fine, he got about a 1/4 mile down the road and it made a kind of fart/backfire noise and quit. It cranks and your can smell gas but it will not turn over and start.
Husband looked at cap/rotor - contacts looked corroded so he replaced. No change - will not turn all the way over and start. This was a vehicle that always started good if it had a working battery so I am still thinking plugs (or wires) but since I have a mental block and resultant fear of electricity I am scared to even check for spark.
Am I on the right track? I don’t want to spend to much on this thing as it is already over $100 to fill it, if I need to spend much I think I might try to get something else running…
On a Ford engine of that year, and with the symtoms you describe, the first thing to check for is a failed timing chain.
Tester
if it is a broken timing chain will the rotor still spin? How else can we tell if it is the timing chain?
Slipped chain will still turn the rotor. Set the timing mark on TDC and see which plug wire the rotor points to. If it isn’t #1 or the fifth cylinder in the firing order, the chain has slipped and you need a new one. The chain might even slip into place again and run for a while, but maybe not long. Start taking t apart and you will know in two hours.
Yes. The rotor will still spin if the timing chain has jumped teeth.
There’s two ways to tell if the timing chain has failed on this engine. One is to drain the oil, and see if there are any bits of plastic in the oil. If there are, these were the teeth from the cam gear sprocket that timing chain turns. And these teeth have broken off and the timing chain is now turning on the cam gear hub.
The other way is, romove the distributor cap. Have someone get on the crankshaft bolt with a socket and breaker bar. Have that person hand rotate the crankshaft in one direction. Now while observing the distributor rotor, have that person rotate the crankshaft in the opposite direction. Determine how far the crankshaft can be rotated before the the rotor in the distributor begins to rotate. If the crankshaft can be rotated 5 degrees or more before the rotor in the distributor begins to rotate, most likely the timing chain.
Tester
Oh brother this is sounding like what it is more and more. I sure thank you for answering. Will check back when we know something for sure.
If it’s jumped time the engine will typically run VERY fast on the starter, but won’t start.
That is to say, normally when you turn the key the engine does something like Rrrrr Rrrrrr Rrrrrr until it starts. If the timing chain has jumped, the engine will have little or no compression so it’ll spin something more like RRRRRRRRRRRRRRRRRRRRRRRRR, but still won’t start.
To verify this one could do a compresion test.
Here are instructions, and picture, on setting the timing chain, camshaft, and crankshaft on time: Click on this link > http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c15280072631
no it sounds fine - just won’t go on over and start