'95 Chevy K2500 Basic Mods?

[stezloco]

Hello ,
having only driven jap pickups and landrovers i was pleasantly surprised to discover the power available in this old chevy.......
a recent purchase of a '95 chevy k2500 6.5td/auto trans, 134,000 mls prompted me to search out the experts and from what ive read so far you're well versed on this motor.....ive got a 4 book set of manuals on the way from the U.S.A to blighty, to help me out as well,cant wait.
have been thumbing through a Chilton manual to read up on some basics ..i'm expecting to be parting with some cash to get this thing to a good useable standard to pull my trailer..so here goes ..
blowby ......its got some...
injectors ..apparently have never been changed...
k+n airfilter fitted...woo hoo
turbo kicks out black smoke on/off/on/off when accelerating.....read its vacuum controlled, not what i'm used to ...can it perform better without the smoke? is there a fault present i'm not yet aware of...i'm not looking for a hotrod or i'd have bought a petrol(gasoline) engined truck ,just want it to run clean and healthy..
looking to change injectors asap and remove the cat section of exhaust.
auto trans seems rough/clunky changing through to drive from park when cold, and the shift light goes out every other position moving from park position.
havent had a chance to get a good look at it yet and its parked up doing nothing.
would like to think its fixable (maybe 'cept the blowby) any comments on basic improvements to this engine would be helpful...i'll be reading through the forum as i get chance and may come across these answers anyway....
lastly ...think yourselves lucky .....we currently pay £1.07 per litre for diesel...x4.5..thats £4.81 a gallon (imp gallon) divide by 0.82 converts that to £/U.S gallon ,x 1.62 current exchange rate, = $6.39 a gallon...(my math correct?)..hows that for ya? its expected to rise in the new year after the V.A.T, (tax) re-instatement back to 17.5% from the current 15%....you dont have it so bad.....yet ....is it time i emigrated ?

[6.5 Detroit Diesel]

welcome to the TDP. your right, everyone here will help you get your truck running best.

a few things. that black smoke is fine and normal. some of us like black smoke and will go to great and sometimes expensive lengths to be able to have black smoke on "tap".

injectors at 134,000, their getting up there. might be time to get some new ones along with a tune from Kennedy or Heath if you are looking to make it run in top form. just a thought.

we've felt the diesel pinch up here in canada. currently in my town, it's more expensive than gas. last year it was up around $5.63 a gallon for a while. kinda makes you think about whether it's worth it to have all that extra power. of course, once you get to working with your truck, there can be no question.

[Artworks]

My mods are in my sig. Black smoke is not normal for these trucks, it may suggest that it is not getting enough ait. Filter & air intake first thing to look at. Then check waste gate operations, linkage / selonoid. My truck will only put out lot of black if I realy put my foot in it and accelorate hard under load. Check out this site with a search for your problems , ask the right questions and someone will usually have answer. I have gotten a lot of hel[p over the 5 yrs. I have had my truck. I would have gotten rid of it years ago without the help of many people on this site. Good luck.

[Robyn]

The 95 6.5 is electronically injected and the turbo wastegate is vacuum actuated and controled by the ECM (Computer)

There is a vacuum pump on the RH front of the engine under the AC compressor.

Make sure you have a good steady vacuum at the pump with the engine running. 26" HG is normal.

The needle on the gauge should not flutter or bounce around. A bouncing needle indicates a bad pump.

If the pump is OK then check to be sure you have a steady vacuum at the wastegate solenoid (Small device at the rear of the LH Valve cover)

Incoming line from the pump should show the same 26" HG just like the pump.

The oultlet side of the solenoid will generally see less vacuum.

Make sure the vacuum lines that go from the pump to the solenoid and then on to the waste gate actuator (on the turbo) are not cracked and leaking.

Check with the engine off to see that the wastegate actuator arm on the turbo moves freely back and forth.

There should be about 15-20" HG vacuum at the actuator when the engine is running and the waste gate arm should be in the closed position and you should not be able to move it.

If the arm can be moved easily when the engine is running then the waste gate actuator is faulty (bad diaphram)

The ECM varies the vacuum to the wastegate actuator (pulses it) to allow the gate to open and close thus maintaining the desired manifold pressure (boost)

These vacuum systems are fine WHEN THEY WORK.

The pumps, lines, solenoid and the actuator are all parts that can and do fail.

The tail pipe should stay fairly clean on these even under hard throttle.

A common mod here is to install a turbo master (spring device that replaces the gate actuator.

A computer chip that will allow more boost and also keeps the computer from complaining if things stray from what it thinks it should be is needed to make this mod work the best.

If you use a turbo master and set it so the boost never goes over about 5-6 PSI you can use it fine with a stock chip.

I would recommned a Pyro and boost gauge.

With the boost gauge you can se what is happening too.

A malfunctioning wastegate system (vacuum or ???? bad) will result in BLACK SMOKE, poor performance and high exhaust gas temperature.

At the present time Diesel here in Oregon is costing me about $2.50 a gallon for ULSD commercial fuel.

Far better than summer before last at $4.50

Running big trucks that get 5 MPG at those prices is insanly expensive.

Check out the system and keep us posted.


Robyn

[6.5 Detroit Diesel]

i would beg to differ that a puff of black smoke coming out the exhaust under throttle is quite normal. excessive smoke if not built for, would point towards something with the vacuum.

[Robyn]

A little "PUFF" just before the turbo spools is fine but if I read the question right, the reference is to periods of smoke while accelerating.

Once the turbo spools a stock truck should run a clean stack all the while its being pushed.

On and off the skinny pedal and allowing the turbo to slow down will see some smoke everytime it has to spool back up.

If the truck has the soot trap (cat) it should run clean.

My 94 is stock and with a totally worn out original cat will kick out a little bit of "haze" but no black SMOKE

Even DaHooooley with the chip and the Turbo master will not cough out BLACK smoke.


Missy