WAY too much smoke--help!

[quinryan]

Inasmuch as I know that diesels are supposed to smoke some, mine smokes likes it was coal-fired instead of oil burning.

Even at idle I get a bit of black smoke (no white, grey or blue), and at anything over 1/8th throttle I can barely see the road behind me. Power seems okay, up until 3/4 throttle or more (I live in Colorado, so that happens a bit), when it acts like it is flooding out. That is, low throttle inputs are crisp. Big throttle inputs are "Huh? What?".

Important stuff- it's an 82 with the 6.2 and 700R4. The heads are refurbed with less than 100 hours on them. The IP is reman. The lift pump may be working properly, but it is augmented with an electric pump. The tank is clean and the lines are new. It has a HUMVEE's intake. (It would have had a HUMVEE's exhaust but I couldn't make the left one fit around the frame without a lot of torch work.)

Mileage seems to be a bit less than what I've come to expect (10-12).

It fires on the first try (usually on the first cylinder) and idles great.

Sooooooo.....

It seems to me that I am feeding the engine (way) too much fuel. Am I right in this? If so, how do I lower the fuel flow?

 

[tRustyK5]

What specs were the IP remanned to? There is a fair bit of adjustability within the IP itself. It could just be turned down to help the issue. How are the injectors?

Air filter...new?

I can get my '83 to smoke decently, but it takes more than 1/2 throttle and even then it's not bad. My IP has been turned up though.

rene

 

[Fordum]

Start where the air enters the filter system, and go all the way to the intake.
Of course, check or change the air filter first.
Make sure you do not have any kind of restriction.
It could have sucked a rag into it somewhere and it lodged.....Or a bird.

You have all the symptoms of a restricted air filter .

 

[quinryan]

Thanks for the input.

The intake is clean. I should have said that this truck was in many, many pieces for a long time (the guy that I bought it from lied to me like a rug) and just revently put the whole thing together.

The air filter is a K&N, plugs are new, injectors are new (reman) as is the IP.

I s'pose that the IP needs to be turned down some. How is this doen without (kicker for me) making things worse?

Thanks

 

[cdoggwsu]

Did they come with EGR in '82?

Mine was acting the exact same way and it turned out to be the EGR diverter valve on the driver side exhaust pipe. I had to pull the vaccum lines for that and the intake manifold valve (which the hummer intake obviously won't have) to get it to run right past about 50% throttle .

 

[K5dreamer]

lots of black smoke, and your crappy mileage indicate a pig rich condition. two causes of this for your diesel. Air restriction cutting airflow into the engine (compounded by the thin air where you live, isnt denver over 5k ft above sea level?), or way too much fuel delivery. either the pump or injectors could be to blame. I suppose its possible they were set up to 6.5TD specs, and are delivering the fuel expecting some sort of forced induction to provide adiquate air flow. Id contact your parts supplyer and double check.

 

[6.2Blazer]

Air restriction (dirty air filter, etc...) or a sticking EGR valve can cause excessive black smoke and it just gets worse at higher RPM's. However, you typically have a noticable reduction in power.

On my '90, prior to going J-code, my EGR would periodically stick and cause light black smoke under moderate to heavy throttle (no smoke otherwise when it was not sticking). But you could also easily feel when the EGR released in regards to power.

I would check the above items first and if they look okay most likely IP needs turned down some. This is manual off the Gale Bank's website, most is for installing the turbo but go down to page 14 for the IP......only difference is you will turn the turn counter-clockwise to decrease the fuel rate.
http://assets.bankspower.com/manuals/656/96291.pdf
I am going to guess that a combination of the IP being turned up some and the high altitude (less air) is contributing to the black smoke.