6.2L - new IP, still won't start

[Rus1]

Hi all, got a '84 K3500 with 6.2L Detroit that I just can't seem to get to start. Here's what I've done so far. Bought it off someone, didn't run, he reckoned it was the IP. I put in a new starter, fixed the glow plug circuit, put all new glow plugs, cleaned injectors with brass brush and acetone, then it fired up OK. Took it out for a test drive, kept stalling out. When it stalled out, it would start fine, but pressing the throttle did nothing for about 5 minutes, then it seemed to work again. Figured it was the IP after all, sent it for rebuild.

So now:

1) Replaced the IP with a rebuilt one from Diesel Care & Performance
2) Didn't start
3) Installed clear lines to observe for air
4) Went on a hunt for air leaks with a compressor
5) Found ratty return line connections at injectors, and fixed them
6) Swapped the canister style filter to a spin on style filter
7) Installed new lift pump
8) Fairly confident there's no air in system, don't really see bubbles. Truck occasionally starts with white smoke, stalls immediately when I let off the throttle
9) Have played with IP timing countless times, nothing seems to improve the situation
10) Cracked open injector lines, there doesn't appear to be any fuel going into cylinders
11) Removed glow plug to watch for mist coming out of glow plug hole while cranking, see nothing

Feeling a bit lost now. The new IP can't have failed this fast, could it? What am I missing? Thank you.

 

[hunters628]

Have you checked to make sure the fuel shutoff solenoid has good power coming to it?

 

[Blue Ox]

Pull the oil filler out and make sure the pin on the drive hub is in the slotted hole in the gear.

 

[Rus1]

Pull the oil filler out and make sure the pin on the drive hub is in the slotted hole in the gear.

That was one of my first thoughts too. But yes, pin is in slotted hole. Probably wouldn't even start poorly like it has if wasn't.

 

[Rus1]

Have you checked to make sure the fuel shutoff solenoid has good power coming to it?

I'll check the voltage. That's the pink wire right? I can see fuel shift a little in the clear tubing when I turn the key/connect the spade. Also hear a quiet 'click' @ IP.

 

[Blue Ox]

That was one of my first thoughts too. But yes, pin is in slotted hole. Probably wouldn't even start poorly like it has if wasn't.

No, that's exactly how they start when they're that far out of time. Crank forever, smoke like crazy, no power, have to keep your foot on it to keep it running. Seen it several times.

If the electrical checks out I'd tee a fuel pressure gauge into the line to the pump. You're looking for around 4-5 PSI. If that's good and you're still getting no delivery it's time to pull the cover off the pump and see what's inside. ***That may void your warranty, so check that out first***

The only other thing I can think of, but it's a long shot, is to verify the firing order. #1 is at about the 10 O'clock position. That, and the rotation is marked on the pump housing. Also, the two bottom lines can be crossed somewhat easily so pay particular attention to those.

 

[MrMarty51]

I got a LP fuel pressure gauge installed on My 2000 K3500. I advise anyone with this base tengine in their truck to install a LP gauge in their trucks too.

 

[Rus1]

No, that's exactly how they start when they're that far out of time. Crank forever, smoke like crazy, no power, have to keep your foot on it to keep it running. Seen it several times.

If the electrical checks out I'd tee a fuel pressure gauge into the line to the pump. You're looking for around 4-5 PSI. If that's good and you're still getting no delivery it's time to pull the cover off the pump and see what's inside. ***That may void your warranty, so check that out first***

The only other thing I can think of, but it's a long shot, is to verify the firing order. #1 is at about the 10 O'clock position. That, and the rotation is marked on the pump housing. Also, the two bottom lines can be crossed somewhat easily so pay particular attention to those.

Entirely possible I mistook the slot for the round hole, I'll have to check that out. I'll check for 12V on solenoid, check fuel pressure, and then maybe I'll do a cylinder compression test. All else fails, I think I'll just call a mobile diesel mechanic. I can spend $500 of my time for nothing, or $500 of an expert's time for results. Will keep posted!

 

[Rus1]

Update - I'm a clown ). Pink wire was going to cold advance, and green wire to shut off solenoid. Now it sort of runs! But with a ton of white smoke and serious trouble idling. Played around with IP timing, didn't seem to make too much of a difference. Doing a compression test next...

 

[Rus1]

Compression test was going very well until cylinder 7, 280 PSI at best. Others sitting at 360-380. Maybe a valve?

 

[mshawn]

Update - I'm a clown ). Pink wire was going to cold advance, and green wire to shut off solenoid. Now it sort of runs! But with a ton of white smoke and serious trouble idling. Played around with IP timing, didn't seem to make too much of a difference. Doing a compression test next...

IP is out of time with the rest of the engine! I’ve don’t this no than once. If the timing gear in the engine moved at all while it was sitting while ip was being rebuilt then your out of time. Or lines going to wrong cylinders

 

[Blue Ox]

Unless somebody cranked the engine while the pump was out it's unlikely the gear teeth skipped time. OTOH, if somebody did that, it could have sheared the key on the camshaft.

Would explain a lot.

 

[mshawn]

Any little roll or movement of the engine will cause this unless you remove front timing cover and find the slot, not the hole that is close to the slot, then it will be out of time. Sometimes the cam can be at right angle that when you pull the ip then the engine moves a little bit. Most people do not pull the top part of the time cover to make sure they are in the slot and not the hole that it will drop in. You can pull the oil filler neck and have sight on the slot but is the rest of the engine lined up on the timing marks. If you stabbed the IP and the slot peas there and not moved them you are good. Did you have it at TDC when you pulled IP? Did you have to move it any at all(engine) to install IP. Also did you get your line installed correctly? Going to the correct cylinder?

 

[Strick]

IP is out of time with the rest of the engine!

These Stanadyne IP's can be a real pain. There is only a couple degrees of timing that you can manipulate with these though. If you replaced the pump and didn't remove the timing cover then there should be no issue with IP timing; the gear will move in the housing but I have tried to get them to jump teeth before and cannot because there's not enough clearance in the housing. The gear will move but not out of mesh with the drive gear.
Have you gotten a replacement IP from another engine or a remanufactured unit? I've had some junk ones that you have to beg to run and then the engine runs erratic and smokes to high heaven. Look on the mount at the front of the block and see if the "0" on your pump matched the line scribed on the engine block. These pumps can be advanced and retarded just a few degrees either way; this makes starting difficult in one direction and a power decrease in the other (which you definitely don't want).

Strickland

 

[Blue Ox]

Really long shot, and since it didn't run before, it's not likely, but it is possible to assemble the injection pump with the driveshaft 180° out of time. If you end up pulling the pump out again, I can explain how you can air time it to check for this.