Headers are glowing!!!!!!!!! UPDATED

[joshm28]

I just put in a new thermostat (there was not one in the truck when I bought it) and when I cranked it up to look for leaks I noticed that the headers were glowing. Before today the truck was hard to start, most of the time, and I was getting a lot of popping from the exhaust. Is this a timing issue or is the carb running to rich? The current set up is an edlebrock 650 carp and manifold with the stock air cleaner on a stock motor. I'm limited in knowledge so I'm not sure what to do to fix the problem or what the problem is. Can anyone point me in the right direction.

 

[bax]

Chances are your motor is too lean. The leaner the mixture the hotter the exhaust temps. Headers do glow but it is usually hard to see it in the daylight.

 

[cmatthews7]

This might sound dumb (but I did it myself) but check your plug wires for the correct firing order into distibutor cap. Dumping raw fuel will cause headers to glow BRIGHT red.

 

[FASTERDAMITT]

If the plugs are black then the headers are burning raw fuel. If thier are white then it is possible you need to adjust your jetting or float.

 

[ak68]

timing

My hedman headers glowed red with the timing too advanced.

 

[cgbexec]

My guess is you are running lean and your timing is too advanced. a 650 CFM carb is too big for a stock engine. You need 400 to 450 CFM for the engine to run correctly. 650 CFM could run a 400 HP 302. Since you are about 150 HP you are way overkill on the carb. That could be partially to blame on running lean.

 

[rattler]

all good answers but more likely to be large vacum leak . That would cause both the lean condition and the exhaust pop.

 

[joshm28]

The timing was actually retarded. But I do have a vacuum leak on the carb. If you are looking at the carb from the front the left vacuum port cap was split. The truck runs 100% better but it is still running rich and I can't figure out how to lean it out.

 

[302fix]

The timing was actually retarded. But I do have a vacuum leak on the carb. If you are looking at the carb from the front the left vacuum port cap was split. The truck runs 100% better but it is still running rich and I can't figure out how to lean it out.

Exec has it. Carb too BIG.

What's your initial timing? Should not be ATDC.

 

[70_Steve]

The truck runs 100% better but it is still running rich and I can't figure out how to lean it out.

With an Edelbrock carb, it's a five minute job (at most) to change out the metering rods. Here's a link to the Edelbrock Performer carb Owners Manual. Everything you never even new you wanted to know, including tuning.

http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf

 

[bmc69]

The timing was actually retarded. .

I got in too late on this one. Exactly..retarded timing casuses both header glow (late fuel burn) and exhaust popping, with the latter worse if running rich.

The only way to change the mixture is by re-jetting the carb, all other things being normal. If the carb is oversized for the application, then you typically cannot jet it down to be on a good/optimum AFR number without introducing an unpleasant bog in yr throttle response.

 

[joshm28]

I just installed a new mechanical water temp gauge so I can make sure everything is running correctly. I started the truck, let it idle for a few minutes then drove it around the block. The temp only showed about 160-170 and I'm running a 195 thermostat. Is this normal? I assume the engine just didn't warm up all the way

 

[feitctaj]

You know Eventually your gonna have to have to answer some of these guys questions so they can help..
Your wandering all over the place

 

[joshm28]

I'm not trying to jump all over the place. I assumed that this was in line with the original post since it all started over a thermostat. I don't know what the initial time was. Unfortunately I don't have a timing light nor the knowledge of how to use one. I loosened the distributor and turned it clockwise several degrees. I know this is not the perfect way but I had to do something in order to take it somewhere to be timed correctly. I installed the gauge to make sure I don't run hot on the trip there.

 

[302fix]

I loosened the distributor and turned it clockwise several degrees...

Perfect. Now were getting somewhere. Advancing the timing should have helped the hot headers...did it?

Around the block may not have been enough to properly test.

Make sure you burped all the air out of the cooling system. Also make sure you have a good 13lb radiator cap. Loosen the cap and let your rig idle until it hits the t-stat temp. You should see fluid movement under the cap. If not burp the upper hose.

Buy a timing light $30 http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=40963
and a vacuum gauge $13 http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93547.

Learn how to set initial timing and then learn how to curve your distributor. You own a Bronco...you need these tools.

 

[joshm28]

Ok I tested it again tonite and turning the distributor solved the problem with the headers. How do I go about burping the air out of the coolant system and how long does it take most engines to heat up to the thermostat rated temp in 85 degree weather. After 20 minutes of running it was still only at 175 degrees. I think I will invest in the timing light and vacuum gauge. The small change I made to the distributor made a huge difference so i am hoping it gets even better when I dial the timing in.

 

[302fix]

... i am hoping it gets even better when I dial the timing in.

Oh baby will it ever!


How are you checking temp? You could have a bad sensor.

Otherwise if you're not getting to temp that means the coolant is circulating through the radiator and not getting a chace to warm up. That points to a bad t-stat or an incorrectly installed t-stat. The spring on the t-stat always faces the engine (although that should keep the t-stat closed).

Start the engine with the radiator cap off. If you see antifreeze movement then get another new t-stat.

 

[cgbexec]

Temperature gauges are not all that accurate. I wouldn't be surprised if they are routinely off by 7 - 15 degrees. If you truely are running 175 degrees for a carb this should be fine. If you are fuel injected you need to get the temp up to about 200 - 210.

 

[joshm28]

I am checking the temp with a new (cheap) mechanical autozone gauge. THe temp probe is in the manifold, driverside front. Could an air bubble in the suystem cause it to not heat up properly?

 

[302fix]

Could an air bubble in the suystem cause it to not heat up properly?

More likely to cause overheating as the coolant won't cycle.

Loosen the cap and let your rig idle until it hits the t-stat temp. You should see fluid movement under the cap.

Start the engine with the radiator cap off. If you see antifreeze movement before t-stat temp then get another new t-stat.