hey,
I had my truck sitting while I waited to buy a new radiator (about a month).I just installed the new radiator but I cant get the truck to start. I installed new plugs and wires shortly before I parked it (about 2 months ago) so I dont suspect thats the problem. What do you think. I suspect that perhaps something is wrong with the distrbutor. The engine rotates but will not start. ANY HELP IS APPRECIATED!!! thanx

 

pull a plug out and check if it sparks. you could have a bad coil.

 

check for spark then check for fuel....if you have those it should start. on my buddy's chev we had minimal spark and lots of fuel..changed distributers and it fired right up.

 

sounds great but how do you increase spark? by upgrading the dist. ? or replacing with another ?

 

If there is no spark the problem may not be the distributor. The dizzy doesn't make the spark it distributes it to the proper cylinder. If there is no spark, it could be a bad coil or a bad amplifier module if you have a duraspark ignition. Pull the high tension lead from the coil to the distributor, hold the end of the lead close to the block and see if there is a spark there. If there is no spark, check that you have voltage at the coil. If there is voltage at the coil but still no spark try a new amplifier module. If that doesn't work, it could be the magnetic pickup in the distributor.

If there is spark from the coil, try taking the distribtor cap off and look at the rotor while cranking. Make sure the rotor is rotating. If it's not it could be the timing chain or the roll pin in the bottom of the dizzy.

If you have spark all the way to the cylinders, check your fuel supply. Plugged filter, stuck float.

Let us know what you find.

 

One of the best checks I use is a used Duraspark module. I keep one as a spare in the truck. Sometimes they die and only another will start the rig. All my Duraspark failures would still get me home; Engine would start after sitting a while, so hard to say if you had a complete meltdown or not....
Mark

 

COMPLETE MELTDOWN !!??? what do you mean? the module melted down?

i tried the spark test and could get no spark, the rotor is turning, I went ahead and got a new dist. cap. but to no real avail, its still is not turning over, i'm looking into the coil and module today, thanx, your help has been invaluable; I will post results of next step. thanx again!

 

I just went through this on my '79 F250.

To start you need only three things - timing, gas and spark. This era of truck has very simple timing, spark and gas delivery systems.

1. Check for timing - pop the distributor cap and turn the negine over. If the rotor turns, you know that at least your timing chain isn't broken. If it's older, it may have stretched and skipped a tooth or two - I know there's way to check, but I don't know it off hand.

2. Check for gas - I figure that if pumpiing that gas pedal while turning the engine over makes the carb stink of gas, then you've got gas being delivered to the carb. A more certain check is to pull the fuel line from the carb, put it in a bowl, and turn the engine over - gas should be pumped out of the line. I just discovered that this doesn't work on many newer cars - the on-board computer won't turn on the electric gas pump until it detects that you have spark, so no spark will cause you to also have no gas. But on these old truck of this forum, the mechancial pump is working as soon as the engine turns over.

3. Spark - start at the plugs and work your way back.
a) pull a plug, put it back in its boot, hold the hex area against the block, and turn the engine over. Should be a fat blue spark. If not,
b)put he plug back in . Pull the main high tension cable from the centre of the distributor. Hold it close to the engine block, and turn the engine over. Same thing, should be a fat blue spark. If yes, then spark is being generated but not distributed. Check the distributor out. If no, then spark isn't even being generated. So,

c) Put the main high tension line back on the distributor. Check the connection between the coil output and the main high-tension wire. Is it plugged in witha good contact? Turn the ignition key 'on' (that is, just 'on', not 'turn over'. Check for 12 volts at both of the secondary coil terminals on the coil by probing the connectors with the connector attached. Do the connectors make a good connection? Are the wires intact? If everything checks out OK, it may be the coil itself. There are ways to check it, but I don't know them so I'd probably end up replacing it with a known-good coil or a new one at this point.

d) IF all this other sutff has checked out, it could be the ignition module. My local PartSource store will do free electrical testing, so you don't necessarily have to buy a new one to try it. One self-test you can do is check for 12v at the red wire of the two-wire connector on the module.

My own no-start tuirned out to be a hairline broken wire at one of the coil secondary connectors.

Best of luck

Admins - is there some way we can compile a "definitive step by step methodology for no-start debugging" page where various suggestions submitted by members are melded into one coherent authoritative article?

 

Hey, that's a great idea! I have responded to many a post in all kinds of forums to just this question...
Mark

 

One self-test you can do is check for 12v at the red wire of the two-wire connector on the module.

I dont understand. Doesnt the two-wire connection provide power to the module itself (incoming power)?*I might be wrong*so dont you have to have it plugged in for it to have the 12 v. So if it is plugged in then how to I test the voltage?

ps I replaced the coil---still not turning over.

is there a place where I can get the wire sets for my module? would like to replace but need the right plugs.

-thanx

 

Fred, It has been done .

The thread is either on this forum or the electrical forum.

maybe search for *Detailed Engine Start Diagnosis (or trouble-shooting)


Sidenote*

One of the biggest problems is Terminology.
Some users say Start when they mean Crank

Then again there are blanket statements instead of precise/specific Info.

 

I posted about a week ago with ignition problems....I followed advice....I got new coil, dist. cap,rotor,ignition module,still not firing. I bought a spark tester and cannot get any spark while the engine is turning(from coil or plug) ......BUT....if I jiggle the battery terminal connections with the key turned on, and the coil lead hooked up to the spark test then I see lots of spark ....

----------WHAT DOES IT ALL MEAN????????--------------

help please..
could it be my eec microprocessor-
or perhaps the stator setup--
????????????????????????
thanx

 

I didn't see your original post but you didn't mention anything about replacing the 'pick up' in the distributor.

Getting a spark while jiggling the battery connection tells me your coil is working since a coil fires a spark when the field collapses (the power is removed from the coil) which is the function of the pickup ( what used to be points in the old ignition systems) in the distributor.

Disconnect the wire from the distributor side of the coil and place a volt meter on it, then crank the engine.You should see the voltage go up and down. If you don't then check/replace the pickup.

 

Go thru the troubleshooting procedure listed in your repair manual. If you do not have a repair manual get one.

 

yeah i have a manual--and I have followed steps accordingly----I am looking to the forum for further suggetions----

thanx for replys