Glowing Headers

[ransil]

The check list I always use:

pull codes
check TFI pins 3&4 run & start signal in the right place
PCV has metered air
Fuel Pressure 28 psi Idle, no vacuum on regulator 35 plus
timing start at 8-10 BTC
triple check firing order ( this is not a chevy its done different)
plug gaps .45-.50
no fancy spark plugs use cheap ones
thermostat 190-195 make sure its not in backwards
Baro/Map sensor mass air should not have a vacuum line connect to it. ( baro sensor)
O2 sensors are left and right make sure they are.
grounds, should have a common ground for the EFI no sheet metal screws in multiple places.

vacuum leak, might need to get a smoke machine, google how to make unless you have access to one they are expensive.

get a EEC-IV breakout box and verify all signals go where they need to go, 2 people can do this in 30 minutes.

and if you have a bunch of brand name parts with lots of fancy names and big number you may just put together a bastard system that will never run. I like factory parts once a shake down run has been done fell free to experiment.

 

[xcntrk]

Not sure if you're past the balancer issue. I would pull #1 plug and manually verify TDC. You can get to within 1 degree using a simple straw. If the balancer is off, clean it with some alcohol and throw some SBF timing tape on it. That's all it takes and you're back to accurate with your balancer.

 

[buckva73]

Dirt; They are new motorcraft wires. Before I go out and buy a new set I am going to check to see if a simple ground strap will help just to check. I know not having enough ground from the motor to the body/frame will make some funky things happen. I have a large ground strap from the intake, cast iron, to the fire wall. Ransil; thanks for the list. Somethings do not apply but its still a good thing to look over. xcntrk; I have and my timing is a little off but not bad enough to cause this. I am going to get that right this morning and work away from that and look at other things that might be causing it. The only things that I have changed during this build is I put in a new wiring harness, a one wire alt, and the hei distributor. I am running stock heads, intake, carb, cam, and bottom end. I did put in new lifters and a 190 thermostat but that is it. The reason I switched the alt and dizzy is because it worked best with the American Auto wire kit for the broncos.

 

[buckva73]

Went out and found TDC on compression stroke. Put the dizzy back in and set it at 12* btdc. Started right up and got the carb adj. with the new settings. Used some carb cleaner and went around the whole motor to see if I had a vac leak. The idle never moved. The motor is now starting to make the headers glow at idle again. about 1-2min after start up on a cool motor. My battery is grounded to the block and the back of the block is grounded to the fire wall. I still have spark jumping all over the place. Off of the dizzy and at the spark plug. I looked with a timing light and if I bump the throttle, the timing jumps 10-12* as it should. Take if up to 3-3500 the timing is at 35* timing. Could it be raw fuel that is not being fired off by the spark plug? Not sure what to try next to get this issue figured out. Thanks for y'all time. Buck

 

[C Saporito]

I'd try ignoring the timing light and just advance the distributor in small increments until the exhaust cools off. You'll probably have to adjust the idle speed also. If it runs good like that you need to re-mark the balancer or adjust the pointer, turning the distributor is not the same.
Check your wires, the glowing headers might have toasted the wires and boots, could be why they are arcing.

 

[EricLar80]

I'd try ignoring the timing light and just advance the distributor in small increments until the exhaust cools off. You'll probably have to adjust the idle speed also. If it runs good like that you need to re-mark the balancer or adjust the pointer, turning the distributor is not the same.
Check your wires, the glowing headers might have toasted the wires and boots, could be why they are arcing.

Heat will definitely cook the wires and may have caused them to break down and not conduct anymore. Now the sparks are jumping off looking for whatever path they can get. Fuel wont burn if incomplete spark isn't there, leading to burning in the headers.

Focus on the sparks first; you wont fix anything until that is addressed. I would say to get new wires or check the old ones really closely and make sure nothing is amiss.

Eric

 

[ScanmanSteven]

I'm running EFI but have had problems with burnt wires from the headers. Like Lars said, try to get the spark issue fixed, I'm thinking a new set of wires. If any of the wires are close to the headers I'd buy some of the ceramic boot ones as they won't burn. You could also use the fiberglas boots to help but they won't hold up to red headers, the ceramic boots will.

 

[Tiko433]

I rebuilt a 302 for my sons 88 last year .. Started it up for Cam break in and noticed one passenger side header was glowing. After trouble shooting I found the injectors on the side where all stuck open dumping fuel in that side . It was a wiring issue. Just something to consider.

 

[DirtDonk]

...Before I go out and buy a new set I am going to check to see if a simple ground strap will help just to check. I know not having enough ground from the motor to the body/frame will make some funky things happen. I have a large ground strap from the intake, cast iron, to the fire wall.

Yes, lack of grounding does make for some funky actions. But in your case, not only is the spark jumping to the surrounding metal (which means it's grounded) but you already have what would be considered sufficient engine grounding. At least as long as the contact points are clean and tight.

The metal of the head and block is the same as the metal of the threaded spark plug port, so to me it does not currently sound like lack of engine grounding. More like bad combustion in combination with what the others were saying about your brand new wires being toasted by the glowing headers.

..I have and my timing is a little off but not bad enough to cause this.

How do you know? Even though you tried fiddling with the timing a little already, doing that seemed to help a little (didn't get rid of it, but helped) why not stick with what was working best, then maybe continue to experiment with timing.

Went out and found TDC on compression stroke.

How did you accomplish this? With the piston top, or the timing marks?

Put the dizzy back in and set it at 12* btdc. Started right up and got the carb adj. with the new settings. The idle never moved. The motor is now starting to make the headers glow at idle again. about 1-2min after start up on a cool motor.

Hmm, sounds just like what one would expect considering advancing the timing before helped, so putting it back would work against you.

I still have spark jumping all over the place. Off of the dizzy and at the spark plug.

Still back to improper combustion conditions, and/or bad wires.

I looked with a timing light and if I bump the throttle, the timing jumps 10-12* as it should. Take if up to 3-3500 the timing is at 35* timing.

Sounds at least like your distributor is functioning properly within it's range.
I'd still go back up with the spark advance though. At least a bit at a time until you find a sweet spot.
But like the others said too, I'm afraid you're looking at a new set of wires just because. Yes, you might end up with a perfectly good spare set, but at this point you know for a fact that you can't trust the ones you have any longer.
However, advancing the timing is free. Adjusting fuel mixtures at idle is free too.

Could it be raw fuel that is not being fired off by the spark plug?

Yep, always could be that. Unfortunately you have other known issues too, which will make finding out why it's got too much fuel a little harder.
Did you mention here what jetting your carb has, or if it's been tweaked? Or is it right out-of-the-box and on the engine?

Hang in there. Lots going on right now for sure.

Paul

 

[pcf_mark]

Listen to Dirk Donk he is leading you on the path to wisdom. If timing had an effect keep exploring that to the end and avoid jumping around. If oyu have bad wires they need to be fixed as an aside (junk yard wires make great test wires for cheapo).

I am still not sure you have both the correct balancer, pointer and number on cylinder figured out. I "fixed" a Mustang the guy said was always hard to start. He had the timing light hooked up to #5 not #1 (both are the first cylinder just wrong bank - Chevy guy). He was running 60 plus degrees.

 

[buckva73]

Thanks guys for all the good wisdom! DirkDonk: Where to start! First off thank you for all the time. I wanted to start fresh knowing more than I did before. I used a piston stop and pulled the valve cover to make sure I was on the right stroke. The 0 mark on the balancer lined up with the timing marker to be tdc using the piston stop. I hooked the timing light up on the pass. side #1 and got it to 12* just because its a good starting point. If I go back to where the headers stop glowing at idle, by the timing light, I am at 30+* btdc. At that point, the headers started glowing after letting it rev 2k-2500 for a few min. When the timing was at 30+* it was not wanting to start real easily. As far as the carb, it is the same one that has been on the same motor for 15+ years. It was just rebuilt for new seals because It had been sitting for 3 years and our fuel is awesome now days. I will pick up some new wires tomorrow and see if we can get the Christmas light show to stop under the hood.

 

[EricLar80]

Don't forget to shut the motor off if the headers start getting really hot. No need to cook new wires...

Eric

 

[buckva73]

LOL Thanks Eric! That is the last thing I need I'm looking right now to see if I have an old set from somewhere just to try.I looked at the wires yesterday and they look great on the outside but who knows what happened on the inside. I bumped the timing back to about 20*btdc at idle and its not glowing as bright but still glowing in 2-3 min. On a bright note, switching to a motorcraft oil filter made the startup tick go away...

 

[pcf_mark]

If it is just idling away will the headers glow? If you hold the throttle open at 2,500 for 5 minutes I bet they glow and that would not surprise me. During cam break in I have seen them get red around the flange at the headers for the first few inches.

 

[buckva73]

Just sitting there at idle at 700-800 rpm. I noticed tonight that It starts at the collector and moves up. They are shorty headers ceramic coated from BC and the 2 into 1 system.

 

[DirtDonk]

Just out of curiosity, and because I don't remember if you said, do all 8 header tubes glow equally? Or at least close to equally?

I'm at a loss with all the new info. If it's not timing (and you did use passenger side front for #1 of course;D), then the only things I can think of that are left are too much overlap on the cam (like a real high-po racing cam) or fuel just dumping into the pipes and igniting after the fact.
But that's such an unusual scenario, that it really does not happen very often on an engine that's running so well otherwise.

Hmm... Exhaust valves not closing all the way? Long shot, but is this an adjustable valvetrain even, or is it stock? I'll go back and re-read, but if you see this first, let me know.

Oh, and what are the engine coolant temps during idle again?

Thanks.

Paul

 

[DirtDonk]

Oh, and way back broncnaz mentioned jetting. Was your jetting ever checked/upsized for the header's better flow characteristics?
I wonder if there is anyone around that can hook you up on an exhaust gas analyzer to tell you if you're lean, rich, or just right. A diagnostic shop, or smog shop (if you have those) in your area perhaps?

Just a thought.

Paul

 

[pcf_mark]

If it starts at the collector that would be odd. If it was hot exhaust exiting the head from a lean mix or late spark wouldn't it logically be a hottest the flange near the head and start glowing there? In my experience the individual header tubes glow but never down to the collector. Glowing at the collector and working its way up?

Could you have a crazy restrictive exhaust? Leaking collector gasket letting in cold fresh air that is lighting off un-burnt fuel (there is always un-burnt fuel at idle)

If it is running and plug the exhaust tip (glove on your hand works) have someone listen for leaks at the collector.

Or they could just be really cheap thin wall headers and we are talking in circles and everything is fine. As Dirt Donk said if you get someone to put a wide band O2 you would know a lot real quick. If you have a friend with an infrared no contact thermometer (http://www.harborfreight.com/non-contact-infrared-thermometer-with-laser-targeting-61894.html) you could take a reading on your actual header temp to see if it normally hot (300-500 degrees for coated t idle) or dangerously hot (above that).

 

[Alpacket]

This is probably wrong, but is it possible your shop accidentally retarded your cam?

 

[68stang73]

I had same experience with a 71 camaro I restored. A few issues were at play. 1- not enough airflow on engine, 2- retarded timing, I ended up at 20degrees initial. 3-And carb jetting to lean. Headers in that scenario started glowing at the bends and worked towards the flange. But would start to grow downward after awhile. If advancing the timing helped but too much made it hard starting then back it off until it starts good while hot. Then get your jetting done. Throw a fan on your motor to help with the flow. But after reading this I have a feeling you burnt your headers to the point it thinned them out. Also you can get an 02 and shove it as far up the exhaust pipe as you can and an autometer gauge aand check your air fuel reading gs too