1994 1Ton 6.5TD hard cold starts.

[Ryan T Kessel]

Okay so Iv been everywhere on the internet looking for a solution to this problem and haven't found one yet... The truck runs and drives perfect with zero issue but, if I let it sit for more then 6hrs or so I will have a long stuttering start with some white then black smoke. Once it starts there is no more smoke and runs prefect.
Quick run down
1994 Chevrolet Dually 2wd 6.5TD Non-EGR
Only modifications done are,
-Manual boost controller set at 10psi,
- New PMD with resistor relocated to passenger side fender well with alum heat sink,
-Air filter and tubing replaced with after market,
-Built 4L80E with B&M trans controller
The new,
-Injectors, injector lines, and recirculation lines with new bosch Oems
-Almost every gasket minus head gaskets
-Water pump/thermostat/belt
-PMD
-All glow plugs are new Bosch(good power to all plugs)
- Map, IAT, CTS
- Both batteries and cables are less then a year old and truck turns over quick.
-Filter housing/water seperator
-Lift pump, filter and ops
- IP less then 3yrs old replaced and set by Twisted Diesel( very respected shop)
I do have a full set or gauges ie.
Pyro, boost, trans temp,
Full exhaust with stacks...I know
Truck was built by HollyRock Custom Diesels in Maryland in early 2000s

This issue just randomly poppes up one day with no codes or other symptoms...
Iv tried everything... Maybe someone has a idea??

 

[Will L.]

NO STARTING FLUID!!! You might know already, but just in case.


First- I'm gonna need pics- I love stacks!

Seriously, the 1/4" return line coming out the front of the injector pump: replace it with clear tubing. Home depot and the like sell it by the foot, you need 4"-6".

Watch it for bubbles when you are having the problem. Not just 1 stagnant trapped bubble, but a small stream of them. This is air in the fuel line.

If you plug in the block heater, does the hard start go away?

Which Bosch glowplugs: 80034?
I have not yet seen a new bad set from bosch, but anything is possible.

Where is your timing set, and was the cam degreed any when built?

You said it cranks over fast- how fast in the tach? Post video maybe?

Has it been like this since it was built, or did this begin after "x" miles?

 

[Ryan T Kessel]

I bought the truck a maybe 5yrs ago now. With 94,000mi and Iv drove it up to 140,000mi now. When I bought it it didnt have the issue. It started doing this about 6 months ago around 135k out of the blue. Block heater plugged in makes no difference. I have double checked batt leads and connections to no avaiI. I dont know off the top of my head what the rpm is when it turns over or the glow plug part# but will take a look tonight when I get home. I kept the box full off the old plugs should ill check the number. I will have to put on the clear line off the front of the IP to check for bubbles. Haven't tried that yet. As for the timing, I couldnt tell you. I dont have all the original paper work from the build just a parts list :\... But I am assuming stock timing because I never discussed changing the timing when it was replaced. Like I said I will install the clear line and double check the rpm and part numbers tonight. Thanks in advanced!

 

[Will L.]

Ok. Db2 can not make up for lost timing due to stretched timing chain like a ds4 does for the first 150,000 miles (after that they cant keep up well either). Every 30,000 miles you need to bump the IP advanced a hair.

Before moving timing, I suggest pulling and bench testing he glow plugs, and while they are out do a compression test. The compression test is the important thing here.

Post up numbers if you can before you put them back in.

 

[Ryan T Kessel]

Gottca. The pump that is in the truck is a DS4 5521. From what I understand, it is the newer DS4? What's the easiest way I could check the timing on it? I have a huge shop full of tools but not much for the diesel world. The glow plugs I am running are new Bosch Duraterm WX-3510373. If done a resistance check on them and a voltage test on all leads and all seems well. Have not done a compression check yet but I will tomorrow when I install the clear line on the IP and check the chain stretch. What are good compression numbers I should be looking for? 400psi after 4 revs?

 

[ak diesel driver]

that's not the bosch number I know of

 

[Ryan T Kessel]

These were recommended to me from a diesel head buddy of mine who has a 2500 with a 6.5.

 

[ak diesel driver]

I did a search and can't even come up with a glowplug with that number

 

[Ryan T Kessel]

My appologies. That part number is for the whole kit not just the glow plug itself. This is the part number on the individual box of glow plugs I installed.
0250202126

 

[ak diesel driver]

OK thats the 80034

 

[WarWagon]

As above put the clear return line on. Air in the system is THE #1 STEP in the GM manual. Overnight any air leaks, that may not show up by also leaking fuel, let air in the system that has to be purged out. The purging process is a white then black smoke show. Pinhole at the pickup assembly on top of the tank is a fun one to find...

Sticking injectors can also do the same - new parts may not be good parts, but unlikely.

You verify you have fuel pressure at the water drain with the lift pump running?

 

[Will L.]

Like mentioned,
Start testing for the air leak with clear return line.

Timing has to be done with a scan tool for that IP. DO NOT try just moving it.

Years ago I quit ohm testing glowplugs. I found bad plugs that passed the ohm test. Only way to test a glowplug is pull it, and bench test it.

So, you said new, but was it new 45,000 miles ago?

Filling out your signature would really help btw.
As for a ds4 5521 being a new style pump not so much

Yes, pull all 8 glowplugs. Disconnect plug going to pmd. Disconnect the multiwire connector to the glow plug controller. When compression testing crank and watch gauge. When you hear it cycles into the tester 3 times and is not raising pressure anymore, that is your reading. 400 is your target. Write down the readings, and post them.