turns but won't start

[oilyfuel]

Here's what I have. 85 k10 silverado 6.2L diesel
Yesterday morning, ran fine. Did the usual manual glow switch (relay cycles fine), held pedal down to keep running until white smoke gone a half block away.
Afternoon, cranks fine but no start.
injection pump solenoid's pink wire activates solenoid when dis/re-connected (I hear sloshing).
Square fuel filter air bleed squirts fuel fine when cranked.
pulled glow plug out, cranked and the fuel mist blasted out fine.
little or not voltage between plug and wire when cycling.

still going to
check voltage between postivie battery terminal and glow plug prong.
resistance (with key off) between glow plug prong and ground (0.8 to 1 ohm max of 3ohms).

Any ideas?

 

[Will L.]

still going to
check voltage between postivie battery terminal and glow plug prong.
resistance (with key off) between glow plug prong and ground (0.8 to 1 ohm max of 3ohms).

Kinda confused myself reading this part...
Check resistance of glowplugs (with wire disconnected) from connector to body of gp. 0.8 to 1 ohm is good if more replace it with duratherms or 60g nothing else.
Check for voltage, identical to battery, at each of the glowplug wires while disconnected from glow plugs.

Once engine is stared but still cold unplug the wire going to the solenoid for high idle to verify it is working.

 

[oilyfuel]

I guess the voltage check doesn't make sense.

With a multimeter, I found:
Infinity resistance on front right two plugs between the prong and ground (engine and battery negative pole).
No voltage between the 2nd to front right glow plug and the battery's positive terminal.
12 volts between the front right glow plug and the battery's positive terminal.

In the past few years at least, in the cold, I've had to hold the manual glowing switch (that I installed) and hold the pedal slightly down to keep the engine running until warmed up and white smoke went away after driving a half block with the glow on. Maybe I left them on too long (longer than usual), burned them out and need new plugs?

I also noticed what looked like liquid under the lift pump. Maybe the pump sprung a leak and isn't putting enough pressure to the IP?

I haven't tested the relay or fusible links with a multimeter or 12v continuity light.
I also haven't tested resistance (to check continuity) between glow plug wire connectors and end at the relay connector.

I guess if the wires are ok, it's time to change the plugs and check to see if the lift pump really has a leak.

This may have to wait a few days until it stops snowing and freezing in the driveway.

I believe I put 60g plugs in here and had them originally when I found one that broke off (cylinder closest to the driver). The Wellmans off eBay I put in died or were defective quick. I'm planning on getting Bosch 80034 Duratherms if I can get them. Oreilly special order hasn't called me back yet, Napa requires prepaid special order, Autozone has them but only ship to home. Amazon is usually quickest, but only 7 plugs. 7 or 7 packs of 8? come on.

 

[ak diesel driver]

good price on ebay

 

[Will L.]

Focus on all 8 gp working properly. Then Identify liquid under the pump- leaking fluid usually means sucking air and harder starts and poor running.

Verifying fuel pressure would be the steps later, but you sound like you are getting enough fuel to fire with the smoke, but if you have the gauge handy it would not hurt. Do you have a compression tester? When you remove all the gp is the perfect time to get the numbers and know where you for this issue and the future.

You know not to use starting fluid unless igniting the fire to collect insurance money right? IDI diesels are way different the DI diesels Starting fluid will kill it quick.

Today was a nice 70 degree day here, how cold is it where you are?

 

[oilyfuel]

Sounds like making sure the GPs are working is a good first plan. There is some question about the plugs and wiring.

I guess discovering the lift pump having a leak is the next thing to look at / fix, regardless of starting.

I don't think I'd ever bother with starting fluid.

Got warm today, 40s maybe? Forecast is 22 tomorrow I think and snow this weekend. I'm hoping the car survives and I don't need 4x4.

 

[Will L.]

I asked about temperature and forgot to ask about using the block heater. Does plugging it in help? Sounds like your cold enough that it should. That s a clue as well of the glow plugs not being in good enough condition.

Another trick that has worked for some people is using a heat gun into the intake. If it is too cold it wont get it but it has worked for me when my gp were bad.

 

[oilyfuel]

Oddly enough, I haven't really noticed lately that the block heater makes much difference. This must have been an increasing problem until this breaking point. I've had to manually switch on the plugs on every cold startup to get rid of white smoke and drive about 30 feet before it's gone and just stutters without them on.

good price on ebay

Thanks for mentioning that. I ordered some there today. Way cheaper than Autozone and Napa and probably same time to deliver. Oreilly never called me back about availability on this, "Special Order" item.

Someone mentioned an east coast trick of connecting exhaust pipe from a warm vehicle to heat up the cold one by pushing hot exhaust through the open cylinders. I suppose it could work, but a heat gun through the intake sounds much easier and better. I contemplated using a heat gun to heat the cab when it was really cold (-10F). Then I thought of rigging a heat gun to the hood to the intake scoop connected to a timer. heh. Might actually work.

Today I tested the glow plug wires and they all seem good. No more leak apparent under the lift pump, so either air sucked in, or only leaking during cranking. when I get the plugs, if I get a compression tester, might test the cylinders if it's not too cold, at the same time observe fuel mist / air purge/bleed, and see if the plugs fix the problem. Otherwise, I'm guessing lift pump has a problem.

 

[Will L.]

I know you don't want to hear it, but your going to have to find that leak. That is most likely part of you problem.

Do you have the clear return line coming out of the ip to watch for bubbles?

 

[oilyfuel]

I bet you're probably right. Once I replace the glow plugs, I'm sure it'll either not start, or still be hard to start. I'll have to check under the lift pump before and after doing any cranking to see if it's leaking. I've also replaced the o-rings on the square fuel filter before and haven't noticed it leaking fuel, but I suppose it could still be allowing air in. I haven't done the clear return line yet. Any idea what size ID that is?

 

[Will L.]

1/4"

 

[oilyfuel]

Thanks!

 

[oilyfuel]

today, cranked, smelled fuel, saw liquid under the pump. must be leaking.

 

[3500GMC]

Check your oil. Sometimes the failed mechanical pumps will let fuel into your crankcase.

 

[oilyfuel]

I changed the the glow plugs and it started up. I had burned out the AC Delcos (Don't know if they were 60g or something else, says 45 on them). I put in some Bosch Duraterms #80034 and it even seems to be running better. Didn't see leaks. Since it started right up, I'm assuming there are none. The lines are old enough to be replaced though of course. Just not today. There is other more importance maintenance to be done. Thanks for the replies!

 

[Will L.]

Cool!