Hard start/engine noise

[tospot]

I replaced the glow plugs with 60g's, should I put the 9g's back in. Engine noise is very loud when traveling at moderate speeds, with just a small amount of pedal pressure noise increases, oil pressure jumps, sometimes it goes past 80psi, seems to increase in power and acceleration while this is happening.If I mash on the pedal, engine is quiet. Anyone run accross this problem? Im thinking injectors/pump. 92 6.5na now TD.

[DmaxMaverick]

Welcome to The Diesel Page!

Put the 9G's back in? NO!! Throw those things as far as you can.

The 60G's require longer glow times to reach the same heat as the 9G's. Can make for "harder" starts. Search the forum for more info on different remedies for it. There are several posts that address that problem.

Is the noise you are hearing after the engine is up to temp? If so, the glow plugs have nothing to do with it, unless you left your 9G's in and they came apart and are rattling around inside.

[tospot]

The noise has nothing to to do with glow plugs, I know that. the noise sounds like pistons banging around,If I let the noise continue it will take off, oil pressure pegs. It will gain 10-15 mph.

[DmaxMaverick]

Did this start soon after the turbo was installed?

If so, Duh! (on me)

That sounds like what happens when the turbo spools up. More noise, more power, more RPM. That's what you put it on for, right? If you are getting more Diesel clatter, your timing may need some attention. Very likely if it quites down with WOT. Could also be a noisy wastegate, if it has one.

More info please. What does the noise sound like? What turbo did you install? Do you have gages (boost, EGT)? You need, at least, an EGT gage. If no gage, you could be overdoing it, and not know until it flies apart. Any other info (total miles, miles on new turbo, other mod's) would be very helpful.

[tospot]

Noise was there before I installed turbo, Odometer shows 339651, but I know it is the second engine. 2nd engine is a reman. the man i puchased from said there is about 150,000. boost gage is all I have. turbo upgraded to a gm6.I only get about 2-3 psi boost when empty.I know the pump needs to be turned up to account for the extra air. The 4l80e transmission got the big boot into the scrape pile. Noise sounds like injector is staying open to long in 1-2 cylinders. it isnt rods or mains but sounds like it, when you step on pedal hard it is quiet and sounds normal. by the way im a truck driver and very familiar with diesels, I did an in frame major on a 3406B, Ran for 450,000 miles before i sold it. Turbo has maybe 5000 miles on it. it isnt getting enough fuel to have a high egt.

[DmaxMaverick]

With that many miles, many things come to mind. Harmonic balancers fail and take cranks with them. Injectors and timing set are very likely with over 150K. Consider 6.5TD injectors and gear timing. Get the pump turned up AFTER you get the noise ironed out. Too much boost/power could be detrimental, depending on what is causing the noise. I strongly suggest installing an EGT gage. Your engine may also be prone to rocker retainer clip failure, which can also create the noise, but is not usually dependent on power output. The list goes on, but you should check out the things that can cause permanent damage first, like the HB and rocker retainer. Also check the torque converter and flex plate, or flywheel/clutch, if you've switch to that. Dual mass flywheels have caused some grief.

Others here are more informed in these areas than I, and they should be jumping any time.

[tospot]

What puzzles me is the spike in oil pressure, there is no fuel in the oil either. thanks for the replies.

[DmaxMaverick]

I wonder if you may have stray voltage or a short somewhere that may be effecting the gage and/or the I/P. Grounding the oil pressure sender lead would peg the gage. Also, an energized HPCA (Housing Pressure Cold Advance--advances pump timing for cold starts) might be coming online after it's warmed up when it shouldn't. That would explain the engine noise. Electrical gremlins!!

[tospot]

dmaxmaverick, thanks for the tip. I disconnected the cold advance, and problem solved, now I need to find the little gremlin and kill it.

[patrick m.]

oil psi guages that exhibit erratic "bounces" or peg the guage, are often caused by a failing sending unit.
if this is the case it stands to reason you could be getting intermitant lift pump operation as well.

on a side note, my eng makes similar noises, such as more rattle at moderate acceleration rates, less with agressive acceleration.

[tospot]

that is exactly what mine was doing. my lift pump is wired direct to the key. I removed the boat achor they call a 4L80E, and replaced it with a 4 speed, manual speed sensor, lift pump gets power thru auto trans. no wires line up yet but Im working on it,Im probably going to wait until I find a 5 speed with electronic speed sensor.

[EscaladeDiesel]

That is exactly the things mine is and has been doing as stated in my most recent "looking for a good mechanic in Dallas/Ft Worth". Can you tell me where the HPCA wire is so that I can try the disconnect?