Hello,

Me again with my weird scenerio of 2 header pipes glowing red hot (2 pipes only).

Well...I took the valves out and checked them over. None of them were bent and they are all seating nicely. I cleaned them up with steel wool and put the head back together.

I reassembled the engine and fired it up. I have to admit, it idles nicely and I cleaned the head surface and the manifold surfaces with a razorblade and it has a nice vacuum seal. As I said, it idles and drives nicely.

So I did the check at night just to make sure the 2 exhaust pipes aren't glowing red hot anymore and there they were.....glowing red hot at idle while all of the other exhaust pipes are normal.

What a dissapointment !!!

I know the old manifold and carb engines aren't as tunned as the new fuel injection engines and some cylinders will run leaner then others and some will be rich, but this is very weird and I am worried about it. They shouldn't be glowing that red hot.

So, what do I do next? The timing seems fine....could it be the carb?

I guess I could run it for a while and then try to read the spark plugs in those 2 cylinders. Last time I looked they were a little rich, but I might have had the carb opened up too much. I've closed the secondaries and put the idle back to the way it was.

I also don't have $500. to just chuck a new carb on the engine.

Any ideas, I'm getting low on them.

Thanks, Greg.

What carb are you running? Can you fatten it up a little bit? Do you have those two plug wires crossed or arcing on each other. Are those 2 valves too tight? 4 corner idle adjustment maybe? Good luck.

-j-rOd

Forgive me for asking, it has been a while since the original post, which 2 cylinders are glowing?

They are the back two on the passenger side. Right by the PCV valve if that would mean anything.

Greg.

I sure hope you have a Holley carb. If you do, pull off the front float bowl and unscrew one of the primary jets. I'd be willing to bet the jets that are in there now are 60's. If they are, pick up a set of 70's and give 'em a spin. I'd be willing to bet that'll do it. If your cam is tame enough, try a 75 or 85 power valve while you're in there.(devide curb idle manifold vacuum by two, for the correct power valve calibration.. 15 inches of vacuum = a 7.5 or "75" power valve, etc. etc..)

It's really starting to sound like you have an extreme lean condition - kinda like hitting the oxygen handle on a cutting torch.. Also, find a PCV valve with a stronger spring with less suck.

[ May 28, 2003: Message edited by: PrimeMover ]</p>

one way to check if the mixture is too rich or lean, is to use the accelerator pump without moving the throttle, which is easy to do on a holley, demon, Q-jet and the like, with the engine at idle, give the pump, not the throttle, a few shots of fuel and see what the glow does, if it gets worse, it`s rich, if it starts to go away, it`s lean. you can do this with slow shots, or fast shots, just make sure you don`t over do it, or the glow will intensify due to the extra fuel. most times headers only glow during cam break in, the only time the engine is held around 2000 RPM for any lenth of time without moving, the lack of airflow causes them to glow, but since your`s glow after the fact, I don`t blame you any for looking into the problem.

DoubleVision has the right idea. You might want run it in to the shop and try an infrared sniff to be sure.

I have a chevey 350 that is glowing 1 header tube. I have tryed everything I can think of. timing, carbs, intake, distributor, compression tests. At this point I think I will remove the head and have it pressure testerd. This problem sucks!

ok, trying to remember the original posts, but you have checked that you do not have a vacuum problem, like a vacuum leak for those 2 intake runners? Could it be a cracked intake for that vacuum run?


Prime and Double, if the carb is adjusted too lean or too rich, wouldn't it be the same for all cylinders and not just 2 in particular? Was just wondering....my son had a similar problem with his 350 and it turned out to be a manifold (vacuum) plug which was leaking. We had to spray some wd-40 on all the manifold vacuum plugs until we found the one that was leaking.

Just my 2cents....

If it idles good and runs good just drive it. I`ve seen this lots of times , it will be allright. A lean cond will cause this to happen, some intakes just do that.

Read the plugs after a few hundered miles,go from there.

Good Luck ;
Troy;

I agree with troy-curt on this. My 440 on my last RV ran with the center tubes on the headers glowing red. I tried everything! several carbs, new edelbrock intake, with and w/out egr, plugs, timing, jets sizes. I called the engineers at Doug Thorley, cuz I didnt want to burn up my new headers, and they told me that is normal on that eng. After more checking around and talking to the dodge people and the RV techs I found on that eng there was nothing I could do to correct that problem. Some engines just do that. WELL they were wrong! I did fix it! I sold it! Now my RV sits on a chevy chassis and no more glowing headers.

so the heat in that cylinder run(s) can't cause a piston meltdown?

If the plug tells you there is fuel there it should be ok.