Problem Confirmation

[mischmat]

So I've been lurking around the forums and youtube for some troubleshooting on some issues with my truck. Basically it's hard to start blowing the usual white smoke.

Step 1: I replace all glow plugs, rewired all new wiring back to the relay with 14awg wire, rerouting it away from all manifolds.

Truck start much better at 0 degrees C. Even without being plugged in.

Still blows white when cold and under throttle when warm. Idles rough cold and smooths out when warm. Under throttle it's rough till the turbo kicks in and blows white. Not water as it doesn't smell sweet and the top end was done ~3 years ago. I saw a video of a similar problem with this unusual knock from another member posted here once the motor got warm. Turns out his issue was injector related.

I'm running down the path right now of injectors... reason being the PMD was already relocated, and the optical sensor in the IP was already replaced, and the roughness of the motor combined with the white smoke is screaming injector to me.

This is my first diesel so I'm looking for an expert to try and confirm my troubleshooting.

FYI, it's a 1994 GM.

[Freddyack]

Do a Search Forum and select advanced search. Type in white smoke for the key words and select titles only. Several threads on this.

If injectors, do a search on injector replacement. Wealth of info on what kind to get, having them tested and how to install.

Good luck

[VanBoy]

Welcome to the site! I, myself, am a new owner of a 6.5L TD also (one week as of tomorrow, 12/24)! At least yours is a 94, no electronic controlled IP....mine is a 95 I have to deal w/ the dreaded PMD...

On the main list of threads in this section (6.5L engine), is a tacked thread that says FAQ (or something). Go to that one if you have not and use your browser search feature. Type in 'smoke'...actually, this is what it says about smoke:

Extended crank time - see hard starting. May be associated with an optical sensor failure on the IP, but not all hard starting is IP related. Cold weather, with a lot of grey/whitish smoke on startup maybe glow plug related. See Glow Plugs for more information. Read up also on fuel supply issues: Lift pump, OPS, fuel line leaks, etc.

You stated your GP's were replaced, so that prob is not the issue then.

[racer55]

Originally Posted by VanBoy

Welcome to the site! I, myself, am a new owner of a 6.5L TD also (one week as of tomorrow, 12/24)! At least yours is a 94, no electronic controlled IP....mine is a 95 I have to deal w/ the dreaded PMD...

On the main list of threads in this section (6.5L engine), is a tacked thread that says FAQ (or something). Go to that one if you have not and use your browser search feature. Type in 'smoke'...actually, this is what it says about smoke:



You stated your GP's were replaced, so that prob is not the issue then.

94 is also a PMD/electronic IP.
PS:I would also lean towards an injector problem-normal maintenance is rebuild or replace injectors every 100,000 miles.
Low compression can also be a factor.

[VanBoy]

Originally Posted by racer55

94 is also a PMD/electronic IP.
PS:I would also lean towards an injector problem-normal maintenance is rebuild or replace injectors every 100,000 miles.
Low compression can also be a factor.

Opps....dang late night posting....meant to type 94...mine is a 94....was thinking his was 93...opps. My error....

[JorgeNY]

How many miles on injectors? They could be the issue.

[mischmat]

Originally Posted by JorgeNY

How many miles on injectors? They could be the issue.

I'm not sure how may miles on the injectors. I can't seem to find any history on them other then a receipt stating one of the owners replaced them.

Originally Posted by racer55

94 is also a PMD/electronic IP.
PS:I would also lean towards an injector problem-normal maintenance is rebuild or replace injectors every 100,000 miles.
Low compression can also be a factor.

Should I still be worried about the IP if the optical sensor has been replaced? The more I read I see alot of people adjusting timing at one point. I downloaded the GMTDScan program and am sourcing out a serial to usb cable to hook up and see what exactly is happening on timing at least I can rule that out.

I haven't checked compression due to a top end rebuild that was done in the past ~5 years or so. I probably should just for peace of mind.

The more I search on the forums the more I'm thinking it's the injectors... I'll try and get a video taken and see if I can post it. May shed more light on the problem for those that are used to hearing the noise of diesel... last time i heard something this noisy it was a petrol motor with a cracked crankshaft.

PS. Cold start this morning and it at least fired on the 1st crank over after rewiring the GP and replacing them. Still takes a couple of tries but big improvement overall.

[mischmat]

Found this video on youtube. It sounds like mine.

6.5 diesel injector knock 2 - YouTube

6.5 diesel injector knock 2 - YouTube

[mischmat]

I've searched on the forums for injectors and have seem many different answers to buying. Some use marine others use the standard bosch. Other than future plans of possibly upgrading the gm-4 to a HX35 should there be any reason to use marine?

Also looking for places to buy I've noticed some use fleabay others use heath, or other retailers.

I found these and another set on accurate diesel, but not quite sure on the fleabay. I noticed people bought from a user moneyslave but appears to no longer have them.

Summit racing also has the Bosch injectors, but I haven't seen anybody even mention buying from them.

Anybody able to point me to a search keyword I may have overlooked or a suggested resaler?

[racer55]

No reason to ever use marine injectors for anything but a boat-standard duty injectors with Bosch,Delphi or Stanadyne nozzles are the way to go.

Kennedy Diesel is a site supporter with quality products.
Otherwise your local stanadyne dealer might be an alternative?