[joed]

from this long, tedious thread :|

http://www.s10forum.com/forum/showthread.php?s=&threadid=76533

Latest problems:

Its' frozen outside, and when I went to go start the s-10 and warm it up...it was acting as if it was running on 3 cylinders.

It was - the brand new Autolite plugs were fouled (3 of them) to the point they would never fire. I drove around on 3 cylinders for as short as possible to go have someone look at it.
*didn't happen as each place was swamped with people freaking out about a little snow that will drop soon tonight.

So I went to shucks and bought the next highest heat range plugs, and go home.

Whoa!
I'm getting this smoke inside the truck building more and more and can't figure out where it was coming from - when I arrived home from the shucks (just up the road basically)...I hear this "sizzling".
I'm freakin out man...what the HELL is that?

I look everywhere, then under the truck. My new flowmaster Cat conv and part of the pipe is RED HOT!! Visibly RED HOT (like in a cartoon red hot).
I shut the truck off asap.

I let her cool. Put the new sparks in (6 in the next highest heat range from stock)...fire it up.
Bamm - works great (even a bit smoother than the other new plugs).
I watch that cat conv like a hawk. Drive it around, check it. etc.
I was burning tons of fuel in the cat basically. Sign the plugs were not doing their job.
Cat isn't heating like that now and she's running well....but man, i can't have this happening (brand new cat which is probably toasted a bit now).

I just had a total tune up (see earlier in this post), but i'm finding out this whole fouling thing happens upon cold starting.

What are all the things that might be the cause to make plugs foul at cold start?

I do have a tough time getting gas in the carb at cold start.
I mean, it's ridiculous how many times I have to start it now.
But....the strange thing is, 3 places don't feel the carb is that bad to cause this. They drove it and looked at it.

So now I'm suspecting:

- bad spark cables (i bought the run of the mill shucks cables).
- flooding upon cold start (I'm trying not to...but I have to give some gas because it's taking way too many cranks with no fire up).

When it fouled this last time, I had to floor and hold the gas pedal to get it to fire...then i noticed the horrid state it was running in (3 cyls) and all 6 never kicked in.
The fouled plugs were: 1, 2, and 6 in the firing order btw.
So how does one start the thing when it's so finicky about flooding or fouling?

Boy, I've sank enough into this little bitch. She rides great right now...but who knows when this will happen again.

any help on causes of this would be great. What does it really mean to put in the next highest heat range plugs?

Thanks and sorry I'm back again with this shit,
Joe

BTW: I should change to a new thread, as the new return spring worked wonders on the aching leg (doh, why didn't I think of this 2.00 part?)

 

[rablair]

Don't worry too much about the catalytic converter if this just happened a few times. If your engine was running well and you were driving 100 MPH your catalytic converter would probably be glowing too. Someplace I have a picture of a Porsche 928 engine on a dynamometer at the Porsche factory and the headers and catalytic converters are glowing almost yellow. I wouldn't do that every day, but you're not going to kill the converter by overheating it once or twice.

You might want to think about rebuilding the carburetor, if the throttle shaft bushings aren't worn out. Rebuilding the carb on a bench will let you clean it all out, replace parts that wear out, and set all the adjustments correctly. If the bushings are worn out then then carb's a throwaway. Carburetor rebuild kits aren't expensive (get the number off of the carb before you go to the parts store), and if you have a clean workbench to work on and are mechanically inclined, it's not terribly hard to do yourself. I've done several succesful carb rebuilds myself, and I'm not a professional mechanic. I've also thrown one or two carbs in the garbage can.

I had a problem with an '81 Corvette 350 with a misadjusted choke on the quadrajet carburetor that missed like that and fouled plugs, but it got better once the engine warmed up. I mention it because the Varajet II carb (I think that's the name of it) on the 2.8 is basically one half of the quadrajet design. You might want to look at the choke and make sure it's adjusted correctly. It was years ago, but I remember the secondary air door spring had to be adjusted just right for the engine to idle and run well when it was cold and running on the choke. My 350 ran so badly and smoked until it was warmed up that I thought that the valve stem seals were badly worn out, but it turned out to be just a choke adjustment.

If you're having problems starting the engine when it's cold then I'd suspect the choke adjustments, but there could be other mechanical problems.

The heat range of a spark plug refers to how fast the plug conducts heat away from the center electrode to the relatively cooler metal of the cylinder head. A hotter plug doesn't conduct the heat away from the center electrode as fast as a colder one, and the hotter electrode is more resistant to fouling (like if you've got bad valve stem seals and the plugs are getting fouled with oil). The hotter electrode will may make the engine more likely to detonate or knock, so you have to get the heat range right, although it can help as a band-aid for a badly running engine that keeps fouling the plugs.

When you start it in the morning, do you always push the gas pedal to the floor to set the choke? That shouldn't be necessary. On the 2.8 I had in my '84 Camaro all I ever had to do was push the gas pedal far enough for the choke to close (you can hear it click), even in cold weather (Chicago winter). I'm wondering if it's flooding before you even turn the key. I once had to jump start a guy's '65 Chevy truck because he kept pumping the gas pedal and flooding it. He did it so much the battery almost went dead because he was preventing the engine from starting by flooding it. He almost had gas coming out the tailpipe. If your problem is really a flooding problem you'd be able to get it running by keeping the throttle wide open while you start it though.

Give me fuel injection any day (at least 1987 and up). Carburetors are complicated mechanical devices, and they go out of calibration way before computers will (some of the old EFI systems are really bad though).