• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

6.5 Hard Cold Start

T

TurboTurd

New Member
Messages
12
Reaction score
0
Location
Wisconsin
1993 K3500 6.5 TD is a having a hard cold start. It usually takes about 10-20 seconds of cranking for it to fire. So far I have New injectors(standyne), new AC delco 60g glowplugs, new lift pump, new fuel filter, new CDR valve, and a new air filter. Truck has 162K miles. The main problem is that the truck will start hard after sitting for 2+ hours and after it does fire it runs very rough and blows alot of white smoke for about 5 or so seconds(60 deg weather), after that the truck doesn't skip a beat and runs perfectly. The truck has always kinda started hard but one morning it got a lot worse. The decline was not gradual.
Here are all of my tests and observations-
-It always starts perfectly when hot. I know common DB2 failing symptoms are hard hot starts.
-I have tested power at all of the glows and they are all working. I get about 5-10 sec. of glow in 60 deg F temp.
-My starter was going out and when I replaced it it cranked faster and took starting time from 50-60 sec to 10-20 sec.
-When cranking I get some white smoke and then all of a sudden it will fire up.
-Truck passes the lift pump test, I don't have a pressure gauge but I can definitely feel pressure at water drain T valve with engine running.
-I also have a dead OPS sensor, I get 12v at the pump but the pump won't run through the OPS circuit. I think I read something about how the contacts inside the OPS are to small and can still pass volts to the lift pump but there will be to much resistance for the lift pump to run. Either way I have it Jumped and its running. Also I know that driving it with a non working lift pump is bad for the injection pump, I have driven it that way for about 500 miles and who knows how long it was driven that way by the previous owner. It started hard when I first bought it (5-10 seconds of cranking) and lots of white smoke. I figured it just needed new glowplugs. So anyway could I have caused damage to IP and is there a way to test/check?
-I have checked the HPCA solenoid on the injection pump and when I apply 12v to it I can hear it click. If I engage and disengage it while the engine is running the engine idle will change So its at least doing something.
-I have a clear fuel return line on the top of the IP and I usually have no bubbles or 1 very small one after letting it sit overnight.
-CTS sensor is open while hot and closed while cold, tested good.
-Lift pump makes more of a clack clack clack noise rather then a normal fuel pump wirrr. Is this normal? FYI it passes the lift pump test.
-I have also checked for blow by and I didn't notice any.
-I have also tried an extended glow time and it makes no difference in start time.

I have run out of ideas and I don't want to replace the IP unless that is for sure the problem. What do you guys think?
 
Might check the fuel line that's before the lift pump. If its drawing in air, that's not good. They're all oring fittings. Steel line can pit and let air in, rubber hose can crack, orings crack etc.
 
Whats the best way to check that? just visually or what? also if it was drawing in air, I would think that it would have problems running, like stumbling and such. or not?
 
I would double check the glow plugs again. If you have white smoke it should start. I manually glow my Bosch duraterms for 20 seconds.
 
:sifone: Getting a 1993 to start is a bit of a trick.

First is making sure there isn't any air in the system. The fuel system will drain down overnight if there is an air leak. Air has to be primed out before it starts. Have a friend start cranking it and watch the return line. Stop at 10 seconds even if it starts and look at the return line again for air. It is hard to see air in the line with fuel moving.

Sticking injectors will have the engine fire and then stall or fall back on the starter. New parts don't mean good parts.

A good way to check for air is to crank without waiting for a glow cycle. Then wait a bit, cycle the glows, and see if it lights right off.

Other sources of air include the fuel filter manager including o-rings and pinholes in the heater. You can change the 1/4" fuel line to the IP without taking the intake off. Remove the FFM, lay across the engine and use a 1/4 ratchet to get to the IP worm clamp on the fuel line by reaching under the intake from the back.

Throttle shaft seals on the IP are known leak points. How much diesel do you see on the IP esp around the throttle shaft? Air can leak without a fuel leak to give it away.

You should use a fuel pressure gauge. Even a temp one. It is possible to have lots of flow and pressure with the engine off and have a plugged tank sock. Engine starts spinning and the pressure drops off.

Glow plugs. Remove an injector from the #1 hole. Cycle the glow plugs. Ummmmm... They are called glow plugs and 60G's will NOT be glowing at 5-10 seconds. The factory controller starts to loose glow time with age. Aftermarket controllers will give you full time on each key cycle so I cycle the ignition 2-3 times to start. Even in 100 degree weather she starts better with 2 glow cycles. There is a resistor mod that goes on the wire from the glow plugs to the relay to get more glow time.

Next advance the timing. The IP is worn from age as well as the timing chain. Advance helps start and clear white smoke. It is a real art to time these engines by ear. A new rebuilt pump sounds different than a worn one.
 
Well I went through your list and I'm still having hard starts. I had a friend crank it and I couldn't see any air in the return line. I can't see any leaks on ip. I still don't have a psi gauge for fuel but it does seem to have enough. I have forced a 20-30 sec. glow and it makes no difference. I advanced the timing 1/8 inch towards the drivers side and while I had the intake off I also turned the pump up. Truck does run better, no more white smoke under full throttle, actually blows just a little black not very much. but it still starts hard. I will get fuel hose today and replace the hose from the filter to the IP since the intake is off. Also would it be a valid test if I pulled the red kill wire on IP, cranked the engine in 2-3 15 second rounds and then reattached it and see if it fires right up? would that show that their is air in their? really don't want to spend money on IP if I don't have to. Thanks for you help.
 
I'd verify fuel pressure. you might be getting some bleed back and a weak pressured LP is taking longer to bring it up
 
You don't need an expensive fuel pressure gauge, the 30 dollar set that reads pressure/vacuum from autozone or harbor freight is perfect for this truck. But you do need one. Do you have a mechanical boost gauge on the turbo? Take it from there and rig it in for the test. It is not just testing if it builds pressure. This will tell you if you are bleeding back the pressure while it cools or sucking air. Tee in before the ip.

Yes a weak lift pump or sucking air takes life off the ip, but i wouldn't be looking there yet. I would be throwing in a set of bosch duratems long before that. Have you pulled a glow plug and watched it cycle? Take a ohm reading of all of them.

Did you use starting fluids? This has a tendency for damage. Burns out glow plugs, breaks them, holes in pistons, etc. don't use any until the week before you want to rebuild the engine.

If you plug in the block heater what affect does that have? What about the hair dryer trick?

What rpm is the engine cranking at? You've seen the difference with the new starter, but you might be turning just a hair too slow still. Good battery cables, good spacer puck between them, strong batteries.
 
How does it run after starting and at what RPM? Constant white smoke after starting? It may need still more advance. Thinking Advance piston is stuck or chain is really stretched.

Press the retard lever in on the bottom on the passenger side of the IP at idle - engine should almost die or otherwise hate it. (Watch it move as you open the throttle with the engine off and manually move it the same way at idle.) No change means piston is stuck and IP needs service.

I threw a Powermaster starter on my 1993 and it started quicker with bad injectors as it spins faster. A failed or no LP pressure at the IP always made mine hard to start. Spec: 100 RPM minimum cold and 150 RPM hot to start.
 
Figured I would make a video of a cold(kinda cold had been sitting for six hours) start. Also I was pumping the gas during cranking. Here is the link http://www.youtube.com/watch?v=spNuUH-V2IE[video=youtube;spNuUH-V2IE]http://www.youtube.com/watch?v=spNuUH-V2IE[/video]

also usually when the truck sits overnight or for a few days it will start in the same manner but will take maybe 10-15 seconds more cranking.

-Before I started it I checked to see if the retard lever moved with the throttle and it seems to move. After I started it I manually pushed it in with a long screw driver and the idle didn't change at all. Only thing that changed is that the engine seemed to clatter a little less. It definitely didn't almost die and the engine didn't seem to mind it. what does that mean exactly? Also the starter, according to dash tach, turns about 150 RPMS. but the dash tach is hard to tell that accurately.
-I also don't think its the glow plugs because I have seen videos of 6.5 starting with bad glow plugs and the seem to kind of sputter to life while mine cranks lifelessly and then fires up perfectly all of a sudden.
-Also I eliminated the OPS from the LP circuit. The LP is now on when ever the key is turned on.
-I will also work on getting a fuel psi gauge. Thanks for everyone's help.
 
Good cranking speed. Smoking white means it is getting fuel, but, it isn't firing at all. This has got glow plug issues written all over it.

The change in clatter means the retard lever is working.

I would jump the glow plug relay with jumper cables, 60G's can take it, and check for voltage at each glow plug connector you can easily reach. I think you broke a wire or burned a fusible link dropping most of the plugs out. Or they are not getting enough glow time. I have to cycle the key 2-3 times to get a good start on duraterms and this is AZ! The 60G's were worse.
 
Yup glow plugs. Cts should be variable ohms based on temp iirc not just open or closed. Somebody correct me if i am off here. Plug in the block heater and put a hair dryer into the intake hose after the air filter. Turn it on high then start the truck. Easy start equals glow plug system issue.

"Pumping the pedal" works good for lack of gasoline in a carbureted gas engine, does nothing for this one. Proper starting is fully depress then release throttle, if ambient temp is below 65*f then hold throttle at 50% (below 30* wot)if above 65 no throttle, then crank.

How did you eliminate ops feed to lp? There is a sticky here to do the lp relay mod. Not using a relay will work for a bit then have problems. Been there done that along with many other people.
 
There is a cold start switch on the t-stat crossover. It is closed cold and open when hot. CTS as said above. May want to verify the system is working as the switch was tested in the 1st post.

Hold the pedal halfway to the floor or floored to help purge air. Pumping doesn't help except the first pump to drop the fast idle solenoid in.
 
Well I think I have found the problem but I am only now more confused and have another problem. I tested for Voltage at all of the wires and everything tests good. Also used one of my old glow plugs and it glowed on every wire. I then tried to remove one of the glow plugs on the driver side and it un-threaded from the block fine(used anti seize when I installed new ones about 3 months ago) but I can not pull it out of the hole. Its like the end has mushroomed or swelled and is to big to fit through. So I then tried to pull the GP next to it and it came out just fine but when I hooked it up to jumper cables it was completely dead. I don't understand how 3 month old ACdelco 60g are dead this quick. Doesn't make any sense. Either way I ran out of time and will continue pulling the rest of the GP's tomorrow. Any Ideas on how to get the GP that's stuck out? Or do I have to pull the head? Really don't want to. I figure if the rest of the GP's come out fine then maybe I can pick up some Bosch Duratherms and just leave the swelled one in... Ideas???

photo (5).jpg

Here is a pic, completely un-threaded and moves in and out about 1/4 inch but won't come out.
 
Leroy sells a tool. I've used visegrips and while turning it back and forth slowly pulled it out and shaved the swelled part off. if it does break off pull the injector and pull the rest out
 
Well I think I have found the problem but I am only now more confused and have another problem. I tested for Voltage at all of the wires and everything tests good. Also used one of my old glow plugs and it glowed on every wire. I then tried to remove one of the glow plugs on the driver side and it un-threaded from the block fine(used anti seize when I installed new ones about 3 months ago) but I can not pull it out of the hole. Its like the end has mushroomed or swelled and is to big to fit through. So I then tried to pull the GP next to it and it came out just fine but when I hooked it up to jumper cables it was completely dead. I don't understand how 3 month old ACdelco 60g are dead this quick. Doesn't make any sense. Either way I ran out of time and will continue pulling the rest of the GP's tomorrow. Any Ideas on how to get the GP that's stuck out? Or do I have to pull the head? Really don't want to. I figure if the rest of the GP's come out fine then maybe I can pick up some Bosch Duratherms and just leave the swelled one in... Ideas???

View attachment 38198

Here is a pic, completely un-threaded and moves in and out about 1/4 inch but won't come out.
 
That one is easy to get to! Sadly the rest are not going to be.

Burning oil sells a glow plug removal tool for this.

I suggest pulling the injector, stuffing a shop towel type paper towel in the precup to catch the tip and then bust it off. The removal tool may do something like this as well.

I know of two things that ruin glow plugs.
Over advanced timing.
Ether starting aid use.

I suspect
Glow plug use when the engine is really hot and running - blows them in half.
High voltage from booster chargers/starting units.
Overheating

I have removed 60G's out of my engine that had nothing but nubs on them. The engine overheated and had ether use to start it and load it on a trailer - only because it had a hole already burned through a scuffed piston.
 
Well crap, I went to pull the other 6 GP and none of them would come out. 7/8 are to swollen to pull out. I tried turning the engine over with them loose but they didn't pop out. Don't know how 60G got fried like this. They're only 3 months old.
 
You must log in or register to reply here.
Back
Top