Well... rebuilt the carb, started it up... results.

[Mercury Mike]

So I rebuilt the carb, tuned it pretty good, everything was looking good, and it started once. Then it died again. I cranked it over, and the carb got a small fire in it! I am at my wit's end AHHHHH I'm ready to pull my hair out. What am I doing wrong? What's going on?!?!

 

[addo]

Your timing's way off. Maybe 180°.

Keep your hair away from the carb. You're too young to remember a Pepsi commercial that went wrong in filming...

 

[Mercury Mike]

Hmm that's weird. I will check the timing again... I reset it to be right on, but I will pull the dizzy and go at it again. No harm in that. I will have all day tomorrow to try it. Hopefully you'll be on Addo you help me a lot! I will check the dizzy timing. It started and ran for a minute... I'm just wondering what the hell is going on inside there for it to keep dying like that. Would that be a symptom of running too rich or too lean? I'm also considering cutting part of the fuel line tube, and putting a fitting with a nipple for a rubber hose, and two clamps. I'm getting tired of pulling that fitting off, and since I lost my fitting wrench, I am using a standard open end 1/2, and that fitting is almost completely stretched. I'll make a quick hardware stop, come back, check the timing, and go from there. Anything else I could check? I was scared as hell when that thing caught on fire, I hit the carb with a pair of pants that I use for oil cleanup, and it went right out. I hope nothing's hurt in there... I am gonna go downstairs in a minute and make sure it's not on fire still hehe.

 

[addo]

You don't need to pull the dizzy if it's 180 out. Just swap the wire "pairs". 1 to 6, 5 to 2, 3 to 4. Then see what happens.

 

[Mercury Mike]

okay I'll give it a shot. We'll see how it goes!

 

[fordconvert]

To confirm if you are 180 out remove #1 plug and slowly crank it over with your thumb or finger over the hole. The compression stroke(the one you want to have the spark on) will push or blow your thumb off. The other stroke is the exhaust so the valve will be open and no pressure. Once you know you have the piston all the way up on the compression stroke pull the dizzy cap and see if the rotor is pointing at the #1 terminal.

You should have a fire extinguisher handy especially when working on old cars that are not working. They make a mess but compared to the mess if those pants would have caught fire...... I have them in all my cars even the '05 and a few big ones in the garage.

Have you done a compression check?
Have you pulled the valve cover and looked at the valve/rocker action? I found out this weekend that you can run them without the valve cover on for quite a while with very little to no oil leakage. If yours dont run you should be able to see something cranking. Maybe you have a stuck valve, flat cam lobe, collapsed lifter, broken valve spring, or bent pushrod? Most of those issues would be obvious even at cranking speed except the flat lobe. I wouldnt expect a flat lobe to cause those problems or happen all of the sudden. Stock cam lift was .245" on both intake and exhaust so they should all be moving up and down the same amount. Its hard to tell with out dial indicators but you are looking for a serious problem so even if you just use a straight edge on the valve cover gasket surface and your finger as a refernce point you should be able to find a bad one easy.

Only other thing that could pop back like that is cam timing, maybe the chain slipped or the key broke? You should be able to get an idea if its way off by looking at the rockers while turning the engine by hand. If its close it will be hard to tell by eye, but close usually doesnt cause fire. A compression check would also confirm if its close.

 

[Mercury Mike]

Can do. I'll make sure that everything's in order and give it another go. I thought I had my dizzy in the right place! Would it start and run, even though it's runnin' real bad, if it was that far out?

 

[fordconvert]

I wouldnt think a 6 would run at all 180 out. A V8 will kinda kick as it shoots flames out the carb but you usually would not call it 'running'.

Let us know what you find when you look under the valve cover. A valve problem would explain a lot of your issues... not all tho, you check the glove box for gremlins or gnomes?

 

[Mercury Mike]

I'll check the glovebox! What'm I looking for under the valve cover? I will get the compression tester from my grandpa tomorrow.

 

[fordconvert]

Have you pulled the valve cover and looked at the valve/rocker action? I found out this weekend that you can run them without the valve cover on for quite a while with very little to no oil leakage. If yours dont run you should be able to see something cranking. Maybe you have a stuck valve, flat cam lobe, collapsed lifter, broken valve spring, or bent pushrod? Most of those issues would be obvious even at cranking speed except the flat lobe. I wouldnt expect a flat lobe to cause those problems or happen all of the sudden. Stock cam lift was .245" on both intake and exhaust so they should all be moving up and down the same amount. Its hard to tell with out dial indicators but you are looking for a serious problem so even if you just use a straight edge on the valve cover gasket surface and your finger as a refernce point you should be able to find a bad one easy.

Do the compression test first since all you have to do is remove the plugs (all of them makes it crank easier). 66 shop manual says 155-195 psi at cranking speed. Allowable tolerance between cylinders 20 psi. Since your engine will be cold and dry I would not worry too much if you get readings a LITTLE out of range but if you got less than 100 in any hole I would go for the valve cover and get a look at the valves.

 

[mkgcars]

If it died and caught fire then I'd say it's flooding - a ton. Result is it kills the motor and then the excessice gas is spilling on to the hot motor and you got flame. Did happen to me back in '80 with my first Mustang.

[This part will sound like a busted record (busted cd? ha!), cause I say it all the time].
My present car ran horrible, flat spots, stalling, etc. I rebuilt the carb a couple of times, would be okay for a month or so and then it would run bad, and it would start flooding.

In my case it was a couple of things:
- fuel pump was putting out 8+ lbs of pressure. Spec is 4-6
- the fuel line fitting on the carb itself was vibrating loose after time.
- lowering the float 1/32 (raising it if you've got it inverted).
- I think the drivability was also helped by rejetting from a 59 to 67. It's getting horrible MPG though and I may try a 64 or 66.

Changing the fuel pump (I used an Airtex. FYI: The originals were AC not Carter. The V8's used Carters but not the sixes) solved the majority of issues. The rebuilds would help periodically help because I'd have a new fuel inlet needle - but it wouldn't last because the fuel pressure would eventually cause it to no longer hold.

For the fuel line fitting I used some lock-tite blue on the threads. First I cleaned it up and let it dry for a couple of hours, then applied the lock tite and then let it sit for a few more hours.

The spec on the float level is +/- 1/32 so no real issue there. Once you get the basic issues straightened out, if it seems like it's starving at higher RPM then go back and reset it.

I got throught it - you can too.
good luck.

matt

 

[Mercury Mike]

Thanks! That made me feel really good, that last part there. =) I have to pick up a bunch of girlies today, they're all dying their hair at my house with my girlfriend... and it's all girls who have either had an eye out for me, or the other way around. It's gonna be an interesting day. I will havemost of tomorrow to get out there any wrench. What do you guys think of using one of those nipple filters, as well? The ones that mount on the carb. Then I could cut my tubing and run a rubber hose, and not have to worry about the leakage.

 

[Mercury Mike]

Sooooo I got out there today. My timing is good. Everything is right in the timing department. The CARB however, needs some more fiddling with. The inlet is leaking, so I'm gonna use the rubber hose and a nipple, with some teflon on the needle. I'm also going to use 2 filters. In-pump and canister. The last problem is that the accelerator pump on the 1940 isn't moving very fast... at all. When I pull it, it moves reallllllly slow up and down, not achieving the quick shot of gas that we all want! =) Soooooo, I am going to pull the carb tomorrow, set up the canister filter, as well as the hose on the nipple, cut the tubing, and make sure that there's no leaks whatsoever of gas. Then I'm gonna change the in-pump filter. With the carb off, I'm gonna get the pump to work good. I am happy, though, I got it to fire up and run for a minute today. That just means there's hope in tomorrow! =) I'm really considering going with a rebuilt carb....... hehehe. Or maybe a brand new holley 2 barrel! =)

 

[pedal2themetal45]

HI
One thing at a time befor you go to the 2barrel......... you need to getit running first.. be for you open another can of worms.......
Are you using a timming light??????????? or are you just going by pulling the dizzy cap and looking at where its pointing ??? That is only good enought to get it started then you need to use a timming light on it to get it right.... Just a 1/4" of rotation of the dizzy can thro the timming off a lot..... They well run 180 deg out.. Not good but well run.. Poping or fire in the carb tells me that an intake valve was open when it fired the plug causeing the fire.. I'd almost bet your still fighting a timming issue..
You siad
""""My timing is good. Everything is right in the timing department.""""
how do you know ir it aint running??
Tim

 

[Anonymous]

Don't rule out the firing sequence either. Although I hate to admit it, I had a 302 in my old '70 p/u (the one that got stolen) and screwed up the firing sequence sooooooo bad. I thought the cylinders were: pass side - 1,3,5,7 and the driver's side 2,4,6,8. Found #1 TDC without a problem and set the rest of the wires counterclockwise - 1,5,4,2,6,3,7,8. The thing started and RAN! It ran like crap but it ran! Backfired through the carburetor a few times, caught and ran rough, but idled. I messed with the distributor and the timing for an hour before I finally gave up and started over.....with the book this time. Talk about feeling stupid! It ran right then. The old engines were VERY forgiving and would take a lot of abuse.

 

[addo]

I even got it wrong with a 4-potter. Had wired it as 1-4-3-2 As commented above, it still ran and would have got you home.

 

[Mercury Mike]

double checked the firing order last night to be sure. 1 5 3 6 2 4. No problem.

 

[hasa68mustang]

I think they are referring to your actual distributer placement not just the wiring... maybe I'm wrong though, I had mine 180* out, it hiccuped a few times and backfired through the carb, then got it straightened out.