Hard starting/white smoke

[mead]

Hello all,
My son's 1985 1028 is experiencing what he calls hard starting.
For the first start of the day, it takes about 3 to 4 seconds of cranking for the engine to start. White smoke comes out of the exhaust pipes for about three seconds, and then it goes into a high idle for a couple of minutes before dropping down to a lower RPM. Other than that, it runs fine all day long, and restarts with no problem at all. My son seems to think there may be a problem with the injection pump, or the injectors.
I was kind of thinking that's just the nature of diesels to be a little rough upon start up, but was curious what any of the other members on here think. Is there a way to test the injectors or the injection pump? I have looked through the technical manuals and can't seem to find that information. Thanks for any suggestions.

 

[91W350]

Weak or non functioning glow plug system.

 

[Coffey1]

I also concur glow plugs check that system out.

 

[mead]

Glow plug relay tests fine, and glow plugs were replaced just a couple of months ago.

 

[Carlo]

What condition are the filters?

 

[mead]

Good question. I will check with him.

 

[nyoffroad]

Glow plug relay tests fine, and glow plugs were replaced just a couple of months ago.

Still could be a bad GP or just a bad connection, this time of year I'm thinking it's more than just one GP, possibly a wiring issue?

 

[91W350]

Or a bad card.

 

[rsh4364]

Mine did this when batteries were bad and didn't spin starter/motor fast enough.

 

[MarcusOReallyus]

Glow plug relay tests fine, and glow plugs were replaced just a couple of months ago.

There's a lot more to the system than just the GPs and the relay testing okay. Have you tested voltages at the GPs while they are engaged?


I suggest reading the GP threads listed in the Useful Threads sticky.

 

[Gripy]

Out of which tail pipe is the smoke coming out?

 

[forest522]

There was a glow plug system guidebook out there at one time. It goes into detail several tests to confirm the system is working. I agree with a previous post, that system is alot more than just the plugs and the relay. A new card may be in order. Without proper warming times and additional glow time that is managed by the card and the temperature sending unit (drivers side rear, behind the valve cover) starts and warming will be difficult.

 

[cpf240]

How was the GP relay tested? What were the readings, and where were they taken? I would also test the glow plugs, just because they are relatively new, doesn't mean one, or more, couldn't have failed already.

 

[mead]

There's a lot more to the system than just the GPs and the relay testing okay. Have you tested voltages at the GPs while they are engaged?


I suggest reading the GP threads listed in the Useful Threads sticky.

We disconnected the terminals from the glow plugs and measured 11 volts when the wait light came on. Is that correct?

 

[MarcusOReallyus]

If ALL the terminals are not connected to the GPs at, and the relay is engaged, you should see full battery voltage there. If it's still stock, you should see 24 volts, if the bypass has been done, you should see 12 volts.

11 ain't right. What do you measure at the battery itself?

 

[mead]

We disconnected each terminal individually to test the voltage, while all the rest were still connected to the glow plugs.
Don't know if the bypass has been done or not. How could we tell?

 

[MarcusOReallyus]

Okay, got to find out if the bypass is done first. Look on your firewall, behind the air cleaner. There's a covered resistor there normally. In a stock truck, it is in series with your 24v buss bar and your GP resistor. One of the recommended mods is the "resistor bypass", meaning that this resistor is bypassed and your GP relay is fed 12v only. Some people will just disconnect the GP from the resistor, and attach that lead to the 12v port on the firewall. Some will remove the resistor entirely, which makes it really obvious.

Look up the "helpful threads" sticky, find the one on the resistor bypass, and study that, including the pictures, to make sure what you have. At this point, I'm guessing you do NOT have the bypass, but either way, we gots ta know!

Check that out first, then measure what you are getting at the GPs without disconnecting any, and then with ALL of them disconnected, and report back on what you find.

 

[MarcusOReallyus]

Any update on this?

 

[mead]

Thanks for checking in. Really appreciate all information. Been distracted with other things but will update as appropriate.

 

[MarcusOReallyus]

Been distracted with other things but will update as appropriate.

Ah knows what that's like!