Smoke screen ahead

[Subzilla]

Traveling home on the local expressway, I see a pure black, intense screen of smoke coming from a vehicle about 20 cars ahead of me as we climb every hill. Looked like the local tire dump was on fire. Cars were actually hitting their brakes as they could not see the road ahead. Coasting down the hill, the smoke ceases. I thought I'll speed up to see if it's a Ford or Dodge. As I near the smoker, I see a stake bed truck pulling a trailer with a Bobcat but still can't make out the brand of truck. I finally get next to him and see a late 90's model Chevy. I'm disappointed. Is there an obvious cause of such a cloud? Shot turbo, bad IP,...

[JohnC]

Originally posted by Subzilla:
I'm disappointed. Is there an obvious cause of such a cloud? Shot turbo, bad IP,... Bad wastegate control circuit.

[ronniejoe]

Yep!

[moondoggie]

Good Day!

"Is there an obvious cause of such a cloud?" Sorry, boys, wrong answer. The correct answer is, this fella isn't a Diesel Page member. ;) If he was, not only would there be no smoke, but there's better than even odds that you wouldn't have been able to catch up to him, because he might be making more power thanks to More Power & the rest of us.

Blessings!

[Bnave95]

How fast was he going with this type of load?
Once pulled my 30ft TT doing 65mph and the ses came on,had lost all my boost.Smoked like your talking, yet droped my speed very quickly to 55 then I let up,got back into the power and the boost came back. Long story short,back when GM did a R&R long block, the nut at the shop had split the rubber connector on the waste gate can.
Would'nt hold boost.So I think? After replacing that pcs. the boost would hold.

[chickenhunterbob]

Oh my,

If I had a dollar for every time I saw a 6.5 chugging black smoke for no apparent reason, and seemingly unnoticed by the operator, I may not be rich, but would be a lot better off.

Sometimes I want to pull them over and have a chat, about vacuum systems, wastegate solenoids, and other such things that hanging around here has educated me in, but haven't yet.

[moondoggie]

Good Day!

"If I had a dollar for every time I saw a 6.5 chugging black smoke for no apparent reason, and seemingly unnoticed by the operator..." Don't EGT's go way up when under load with inadequate air? Your observation may explain at least some of the 6.5's earned or unearned reputation for unreliability - clouds of black smoke should be fixed. ;)

Blessings!

[Jim Griffin]

What a great site this is! I'm a newbie here, and just became the proud owner of a 1994 CK2500 in December. I've been slowly perusing the volumes of info here, and trying to figure out what questions to ask first...well it's been a few days since I was here and lo and behold this whole topic was my next inquiry of the experienced here since I have noticed some smoke under load coming up the hill from town (Denver 5280 ft to home 8000 ft)...I thought it might be something to do with the turbo operation but wasn't sure where to start troubleshooting. Now I know what to search for here...I'll be checking my vacuum systems, waste gate operations and solenoid and staying tuned in here to see what else I need to learn...thanks for sharing the info all y'all.

[Bnave95]

What a great site this is!

You got that right :D Back when I first joined I knew nothing about the 6.2-6.5 diesel. I found my truck,needed a newer work truck and wanted it to be a diesel. If it was'nt for this site I would of gotten rid of my truck long time ago.
Thanks to MP and all of the members I have been able to up grade power and make the truck very dependable. Thanks to all of the members also,I can't keep my hands off of it even though nothings wrong :D Cut my finger yesterday,bleed black :confused: tongue.gif

[DA BIG ONE]

Originally posted by Bnave95:
What a great site this is!

Cut my finger yesterday,bleed black :confused: tongue.gif Quick, back to area 51 for overhaul.

[Subzilla]

He was going about 55 (the speed limit), and he may have been slowing up hills but he was pulling a normal size Bobcat skid steer loader. But, again, the black smoke was unreal! My first thought was: "Does he even have a clue how far past 1200 degrees his EGT's are exceeding?" When I push my old 6.2 to roll out the black smoke, the EGT's climb quickly, but my black puffs are nothing compared to what this truck was putting out.

Just trying to pick up some 6.5 knowledge for when the day comes to modernize one of the vehicles. I concur with the other comments on the valuable info I've learned here. I can't even begin to count the hours, dollars and frustration I've saved over the last 9 years by being a TDP member!

[Cowracer]

Well, when he cracks a piston, the smoke with take on a bluish tint. And when the head gaskets let go, it will have some white mixed in.

Pretty!

Tim

[autocrosser]

Everyone seems to overlook the posibility of a plugged cat converter. If the waste gate is functioning ok the next and quickest thing to look at is the converter. I've posted this comment a number of times due to folks blastiing out black smoke and having a loss of power and elevated coolant temp.finding them plugged at the inlet.

[TJ]

There are people still using their soot collectors??? :eek:

[chickenhunterbob]

I suspect people (at least a few) still use the catalitic converter.

But the (first, if is suspected as a problem) remedy for a plugged cat from the GM manual it to floor it a few times to the allowable speed limit, to clear the accumulated crud.

[autocrosser]

That remidy has never worked on the ones I've seen. The screen at the inlet were so plugged it wouldn't self clean. That might work for one the is caught early.

[Bnave95]

The screen at the inlet were so plugged it-

The trick has been to remove Cat. Debug inters,install pipe in Cat. Look as though Cat is still installed.

[turbovair]

If that guy had a boost and EGT gage, he'd be aware of his problem!

[ToddMeister]

If the guys cat was plugged he wouldn't be pulling that load at 55, and truck won't pull itself at 55 with a plugged cat either.

[autocrosser]

My son was able to pull my my trailer with my John Deer Tracror on it with his 95 cat plugged, it did run a little warm though. He was running at highway speeds.

We cut it open and removed the guts and welded it shut so it looks like it still has a cat. M96 has the cat removed. We both live in a non emissions county.

[tehillah1]

I'm getting the hang of this...My '94 CK2500 has been doing "puffing" a bit more than I like when I get in the peddle coming up from town (Denver/5280 to home/8000'). After reading up in the forums, checking out the member's areas and getting some info down I ruled out my vacuum pump as the problem: 18+" from the pump to the solenoid (found out what and where that was here at TDP). Next part was finding no vacuum from the solenoid to the Waste Gate. This after ascertaining I COULD move the WG rod while the truck was running.
After doing a little more "banging" around, literally, banging on the solenoid, I got some intermittent vacuum, from 5-10" at the WG end of things.
Went back to the member's area and pulled down the info for checking the SES codes and 'lo and behold I'm flashing a 78 (WG Solenoid of all things...). I call the my closet GM dealer and he's asking someone behind the desk w/him about which part is which and quotes me a price on the WG actuator...I've got the PN from TDP and finally find the right part, right price at the not-so-close truck center out in Henderson.
All that to say, this is the place to be if you're driving a GM diesel and want it to run the way it was intended to. Thanks all.

[rdurh]

I had pretty much the same issue driving here in Colorado Springs. Called the local Chevrolet dealer and they wanted close to $100 for the Waste Gate Solenoid. I ended up getting one from Rockauto for just over $40. Dealer also wanted a little over $240 for the Boost Sensor. Got it from Rockauto for just under $50.

[BobND]

After doing a little more "banging" around, literally, banging on the solenoid, I got some intermittent vacuum, from 5-10" at the WG end of things.


The wastegate solenoid is "duty cycle" controlled, meaning is is steadily pulsing, so it does wear out, and can get sticky. The longer the solenoid remains in the "activated" position during each pulse cycle, the greater the average vacuum is to the wastegate controller.

Very likely, a new solenoid will fix the problem, however, be aware the wires at the "solenoid bank" commonly break. They must vibrate a lot at certain RPM's, as I have dealt with at least 3 instances where there were EGR or boost solenoid problems that were due to the wires having fatigued and broken within and inch or two of one of the solenoid connectors.

You can lightly tug on each wire, observing whether the wires are good, or whether the wires are broken inside the insulation, in which case the wires will stretch easily, as the insulation is all that's holding them together.