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Well, just got a 72' F100 4x4 4 speed truck. Got it a couple days ago for $700. It's got the 360 motor. Now, it's got a problem with the distributor. Whenever you tighten down the clamp that keeps it in place, it misfires like crazy. Does anyone know why it does that?
Are you sure the Dizzy (distributor) is all the way down resting on the block? Sounds to me like the PO (previous owner) put that dizzy in there one tooth off so it doesn't want to go all the way in.
Are you sure the Dizzy (distributor) is all the way down resting on the block? Sounds to me like the PO (previous owner) put that dizzy in there one tooth off so it doesn't want to go all the way in.
Yeah your probably right, should I pull it out and try setting it back into the block? How do I make sure it's on the right tooth?
x2 on not seated tho!..
But check the inside the dizzy & cap & rotor for any loose or damaged. While dizzy cap is off check rotor shift end up & down & side to side play for looseness.
I've have heard that some guys had troubles with the Chinese Dizzy/oil-pump drive rods being too long for some after market hex dizzy rods. Don't know how true that info was.
May have a cracked lower housing from someone trying to pull it out wrong. Or from not removing the dissy when pulling intake manifold..
Now way did you have to mess with dizzy in the first place?? That would cause it not to seat all the way down.. ???
Now way did you have to mess with dizzy in the first place?? That would cause it not to seat all the way down.. ???
well because when i bought the truck, the previous owner told me when you tighten in, it misfires. so i tested it, and it DID misfire... really bad. and he already changed out the cap/rotor, wires etc. so when i have time this week iltry pulling it out. how do i make sure its seated correctly? thanks!
Right where that bolt and clamp are you were tightening the Dizzy's housing should be resting directly on the block. Did the PO replace the Dizzy? If so it sounds like post above was correct that the hex hole in the bottom of the replacement Dizzy's shaft is not deep enough. That hex hole is where the oil pump's drive shaft goes in.
Right where that bolt and clamp are you were tightening the Dizzy's housing should be resting directly on the block. Did the PO replace the Dizzy? If so it sounds like post above was correct that the hex hole in the bottom of the replacement Dizzy's shaft is not deep enough. That hex hole is where the oil pump's drive shaft goes in.
no, he said he didnt replace the dizzy but he did say he pulled it out to skip a tooth for some reason? not sure why he did... but seriously, the truck runs perfect when its not completely tight, but once u tighten the clamp, it misfires.
no, he said he didnt replace the dizzy but he did say he pulled it out to skip a tooth for some reason? not sure why he did... but seriously, the truck runs perfect when its not completely tight, but once u tighten the clamp, it misfires.
If we are right, you tightening the Dizzy is pushing the housing down. But the oil pump and it's shaft won't let the Dizzy's shaft go down with the housing. Housing down and shaft staying up equals messed up operation of the points. Erratic points gap gives erratic coil saturation. Which gives you erratic spark.
But I still don't know for sure yet if your Dizzy is flush with the block or not. Please check that 1st before we worry about anything else.
If we are right, you tightening the Dizzy is pushing the housing down. But the oil pump and it's shaft won't let the Dizzy's shaft go down with the housing. Housing down and shaft staying up equals messed up operation of the points. Erratic points gap gives erratic coil saturation. Which gives you erratic spark. But I still don't know for sure yet if your Dizzy is flush with the block or not. Please check that 1st before we worry about anything else.
No, it's not flush with the block right where the clamp is
No, it's not flush with the block right where the clamp is
OK. Now we're cookin' on the front burner. What we have to do now is figure out what the PO did and how to solve the problem. There is no reason just out of the blue why he would have to yank the Dizzy to move it one tooth. Unless he replaced it and popped it in a little off so Vacuum advance wasn't pointing where he wanted it. I think he Bull-Steined you. Wouldn't be the 1st time a seller lied. He probably put a used Dizzy in there. A new or rebuilt one is probably what it's going to take but let's work with this one 1st. I'd bump the engine around untill the rotor was facing somewhere forward. Mark on the Dizzy housing exactly where the rotor is above it so when you put the dizzy back in you can line the rotor and housing back together so the engine will be pre-timed. Pull dizzy and see if you can see anything on dizzy (a ridge maybe) or on the block that would hold it up. Anything stuck up in the hexhole on the bottom of dizzy's shaft? Try popping the dizzy back in a couple different clock rotations see if you can get it all the way down flush with block.
OK. Now we're cookin' on the front burner. What we have to do now is figure out what the PO did and how to solve the problem. There is no reason just out of the blue why he would have to yank the Dizzy to move it one tooth. Unless he replaced it and popped it in a little off so Vacuum advance wasn't pointing where he wanted it. I think he Bull-Steined you. Wouldn't be the 1st time a seller lied. He probably put a used Dizzy in there. A new or rebuilt one is probably what it's going to take but let's work with this one 1st. I'd bump the engine around untill the rotor was facing somewhere forward. Mark on the Dizzy housing exactly where the rotor is above it so when you put the dizzy back in you can line the rotor and housing back together so the engine will be pre-timed. Pull dizzy and see if you can see anything on dizzy (a ridge maybe) or on the block that would hold it up. Anything stuck up in the hexhole on the bottom of dizzy's shaft? Try popping the dizzy back in a couple different clock rotations see if you can get it all the way down flush with block.
sweet, thank you. yeah tomorrow after work il have to go out there and pull it out, i dont remember why he did (he told me why) but i cant recall. but anyway, il post up what she looks like tomorrow.
if it turns out that you do need a new one i highly recommend upgrading to an HEI unit.
i bought a rebuilt one from the parts store. the points were worn to begin with and after a few weeks the vacuum advance mechanism failed and the engine would fall on its face. HEI makes it fire right up runs a heck of a lot smoother than any ol points do, and mine came with a unlimited abuse lifetime warranty. only drawback it the big cap and different style wires...