84 diesel crank no start.

[k5blazerguy]

I just acquired an 84 been sitting for 8-9 years. I know nothing about it or condition of motor and this is the first 6.2 I’ve ever messed with. Towed it home and put few gallons of fresh diesel in the tank with some seafoam. Unscrewed top bleeder from filter until fuel steady stream no air. Cracked a few injector lines and have few drips out of each one cranking engine. The engine cranks, no smoke out of tailpipe, doesn’t attempt to start. Noticed the glow plug light didn’t come on the dash. Not getting power on other side of relay. Also not getting power to glow plugs. Used a jumper to apply power and glow plug light came on, got power to glow plug connectors,….waited about 5-10 seconds and start. Repeated process. Still same thing. No attempt at all to want to start. Just crank. Batteries seem fine. I had them on a charger for hours as well as connected to jumper cables to my other truck. Before I start replacing everything, hoping there’s something else I can try. I do have power on the injection pump and can hear it click when I connect the pink wire back. I wanna see if the engine runs before I dump a buncha money into it on maintenance stuff. If I can start it, I will prob replace manifold with non EGR and put new injectors, filters and glow plugs just to freshen up the motor.
Any ideas? Could it be bad glow plugs? Am I ok jumping the relay for 5-10 seconds at a time?

 

[cheavyk10]

Not sure about the civilian models but the CUCV starting instructions say to hold the throttle down halfway while cranking above 32°.
I might also try a shot of ether if that doesn't work.

 

[kennyw]

Not sure about the civilian models but the CUCV starting instructions say to hold the throttle down halfway while cranking above 32°.
I might also try a shot of ether if that doesn't work.

Yes to half throttle. ABSOLUTELY NO to either. That is the fastest way to destroy an IDI diesel.

You can do a quick test on the glow plugs with a 12V test light. Clip the ground alligator to your battery positive post and touch the test probe to the glow plug spade after disconnecting the wire. If the bulb lights up, it may be working. If not, it is dead and burned out. This test doesn't guarantee they are performing great, but it does find the dead ones quickly.

 

[CT-BLAZER]

Use a DVM + test. each glow plug separate... Unplug them before testing.

I've used penetrating oil sprayed in the intake to get a dry diesel primed + started.

??? You should see smoke from the truck trying to start it.

The truck is probably still suffering from the same reason it got parked.

 

[Cucv_M1008]

Not sure about the civilian models but the CUCV starting instructions say to hold the throttle down halfway while cranking above 32°.
I might also try a shot of ether if that doesn't work.

Use WD40 not ether

 

[kennyw]

To jump the solenoid, are you going from 12V+to trigger +?

 

[Barrman]

You have the octopus stock glow plug controller. They were problematic when new. That is a worry for a later time though. I suggest you start by checking the glow plugs. You can Ohm check them in the head. But I would pull them to see what brand and model they are and make sure none of them are swollen. I like Delco 60G glow plugs because they are self regulating and in theory can be held on until your batteries go dead without anything bad happening. Here is a video about glow plug testing:

Once you verify all 8 glow plugs are good and there is continuity between each of them and the orange wires on your fender at the relay. Just get 12 volts to the orange wires for 10-15 seconds. I like using the remote trigger starter jumpers auto parts stores sell to hot wire my glow plugs in situations like yours.

That takes care of the heat needed to start. You stated the batteries were good and the engine was turning ok. That is the rest of the heat and the compression needed to start. You probably have air. Which leaves fuel.

Did you pull the pink wire off the Injection pump when you opened the fuel bleeder and spun the engine? If not, you probably introduced air into the IP. You just need to crank it to get it primed again. here is a video about that:

If you get more than 4 minutes of cranking time without fuel at the injectors. Or, if you spin it with the glow plugs out it will really spin over fast. A fuel fog will form out of the glow plug holes when you have fuel. If you don’t get fuel. Then checking the pink wire for power, the solenoid in the IP, the lift pump, the fuel hose on the frame rail before the lift pump, the fuel hose on the frame rail under the passenger seat and the hose at the tank for cracks need to get looked at. Along with the fuel pick up in the tank. Here is a video about the pink wire:

The 6.2 is a nice dependable economy engine once you get everything base lined and do normal maintenance. Hopefully yours is like that for you.

 

[k5blazerguy]

??? You should see smoke from the truck trying to start it.

I’m just thinking of my 12 valve even if the IP is disconnected it will still throw white smoke out the tailpipe tryin to start. (Took me a sec to figure out I forgot to connect that wire back. lol)

To jump the solenoid, are you going from 12V+to trigger +?

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Tried that and my volt meter was still showing nothing on the other side. I’m sure this solenoid is probably bad. I may do a momentary switch, but I also like factory stuff working too.

 

[k5blazerguy]

You have the octopus stock glow plug controller. They were problematic when new. That is a worry for a later time though. I suggest you start by checking the glow plugs. You can Ohm check them in the head. But I would pull them to see what brand and model they are and make sure none of them are swollen. I like Delco 60G glow plugs because they are self regulating and in theory can be held on until your batteries go dead without anything bad happening. Here is a video about glow plug testing:

Once you verify all 8 glow plugs are good and there is continuity between each of them and the orange wires on your fender at the relay. Just get 12 volts to the orange wires for 10-15 seconds. I like using the remote trigger starter jumpers auto parts stores sell to hot wire my glow plugs in situations like yours.

That takes care of the heat needed to start. You stated the batteries were good and the engine was turning ok. That is the rest of the heat and the compression needed to start. You probably have air. Which leaves fuel.

Did you pull the pink wire off the Injection pump when you opened the fuel bleeder and spun the engine? If not, you probably introduced air into the IP. You just need to crank it to get it primed again. here is a video about that:

If you get more than 4 minutes of cranking time without fuel at the injectors. Or, if you spin it with the glow plugs out it will really spin over fast. A fuel fog will form out of the glow plug holes when you have fuel. If you don’t get fuel. Then checking the pink wire for power, the solenoid in the IP, the lift pump, the fuel hose on the frame rail before the lift pump, the fuel hose on the frame rail under the passenger seat and the hose at the tank for cracks need to get looked at. Along with the fuel pick up in the tank. Here is a video about the pink wire:

The 6.2 is a nice dependable economy engine once you get everything base lined and do normal maintenance. Hopefully yours is like that for you.

I know I’m getting 12v to the GPs after jumping the solenoid with a wire. I’m betting that solenoid is bad. I didn’t realize you needed to unplug the IP hot wire while bleeding. I can try that again. So, if I’m getting fuel to the injectors then more than likely could be Glow plugs are bad what it seems like. From what I’ve read this motor still needs glow plugs in hot weather?

So for now I can continue to hot wire the GP solenoid to heat up the plugs, but I sounds like I should prob just replace the glow plugs. If I can just hear it run then I’ll replaced everything on it. Just tryin to see if the motor is good.

 

[Barrman]

Just to see if it runs. jump the glow plugs 10 or so seconds, crank 20-30 seconds, wait a few minutes, repeat.

The 6.2 will put white smoke out with fuel and no glow while cranking. No smoke of any color normally means no fuel.

159° inside the engine or lower for the 6.2 is considered cold And glow plugs needed.

 

[k5blazerguy]

Just to see if it runs. jump the glow plugs 10 or so seconds, crank 20-30 seconds, wait a few minutes, repeat.

The 6.2 will put white smoke out with fuel and no glow while cranking. No smoke of any color normally means no fuel.

159° inside the engine or lower for the 6.2 is considered cold And glow plugs needed.

I was kinda thinking same thing I wasn’t getting enough fuel. I cracked a few injector lines and had few small drips. But I’m not sure what’s normal. I know the 12 valves will spray out the lines when bleeding. But no smoke out the pipe should mean no fuel. May be a combination of not enough fuel and bad GPs.

 

[Barrman]

Verify the IP solenoid is getting power and clicking. Then crank it over. You can crack the lines at the injectors but it really doesn’t help and just makes a mess.

Since you have a 12 valve. If this 6.2 runs you need to be aware of the design goals of the 6.2 From 1979.

Fit where a small block Chevy gas engine would, make the same power as a 2 barrel 305 and get twice the mpg of the 305.

That was the goal and it was met perfectly. Notice trailer pulling or going up hills without slowing down or even running 70 down the highway is not part of the goal? Without a turbo on the 6.2 you will be let down by the performance compared to the 12 valve. Even with a turbo you might be let down. However, they are half the weight of a 12 valve and in 4 low are amazing off road.

 

[k5blazerguy]

Verify the IP solenoid is getting power and clicking. Then crank it over. You can crack the lines at the injectors but it really doesn’t help and just makes a mess.

Since you have a 12 valve. If this 6.2 runs you need to be aware of the design goals of the 6.2 From 1979.

Fit where a small block Chevy gas engine would, make the same power as a 2 barrel 305 and get twice the mpg of the 305.

That was the goal and it was met perfectly. Notice trailer pulling or going up hills without slowing down or even running 70 down the highway is not part of the goal? Without a turbo on the 6.2 you will be let down by the performance compared to the 12 valve. Even with a turbo you might be let down. However, they are half the weight of a 12 valve and in 4 low are amazing off road.

Yeah I’ve never driven a 6.2 but I wasn’t expecting much from it. Just excited to have one. The IP is clicking when I connect the pink wire so I would assume it’s working. Gonna go ahead and replace all the GPs and fuel filter then bleed the system again and see how she does. Fingers crossed the motor is good. If if runs, I’ll be looking for a non EGR intake to swap with. Then do 1/8” fuel turn. It’s a clean truck. Would make a fun daily driver.

 

[Barrman]

Don’t expect more than a wisp of black smoke out the tail pipe on hills from the 1/8 fuel turn up. Getting the timing right for your engine and your elevation will give you a more seat of the pants feel improvement. Turbo is the only thing you will feel after the first test drive.

 

[imiceman44]

Yeah I’ve never driven a 6.2 but I wasn’t expecting much from it. Just excited to have one. The IP is clicking when I connect the pink wire so I would assume it’s working. Gonna go ahead and replace all the GPs and fuel filter then bleed the system again and see how she does. Fingers crossed the motor is good. If if runs, I’ll be looking for a non EGR intake to swap with. Then do 1/8” fuel turn. It’s a clean truck. Would make a fun daily driver.

If you get it running and you need parts, let me know.
I also have a non egr intake ready in box to ship.

 

[2INSANE]

Any luck so far?

The first thing I would do is install a clear hose from IP return nipple to return line. This is a super cheap way to diagnose any fuel issues.

You could also install an inline fuel primer to help prime the fuel if you still have a mechanical fuel lift pump. A lot of times that mechanical fuel lift pump quits working. Sometimes it’s best to just take it off, put a delete plate over it, sell the pumps rod for $40 to Bostic Motors and install an electric lift pump instead. It really solves a lot of problems.

Next up would be your heat! Glow plug that is. Best mod is to bypass the Oem stuff and go with a mechanical push button. If the ohms read good on the glow plugs, I wouldn’t waste the money on new Gps.

 

[k5blazerguy]

If you get it running and you need parts, let me know.
I also have a non egr intake ready in box to ship.

I wish I had seen this before I just bought a J code intake. lol. This truck survived the fires. Was the only truck in my back yard I couldn’t get out in time that survived. So gonna get back on it and make it run. My son will end up with this truck for high school. Ordered a set of glow plugs and new relay solenoid hoping that’s why it won’t run. May finally have time this weekend to mess with it again. Just getting caught up on everything.
I’ve never owned or driven a 6.2 so excited to get it running. Been looking for a Banks kit for it and found a guy in CO that has the turbo and some pipes but not the manifolds or crossover, so don’t think I can do much with that. I don’t think I’ll find those parts so makes the turbo useless. May end up researching the 6.5 turbo to add onto it once I can get it running. I know it’s not gonna have any power compared to my 12 valve. But I think keeping this truck with the 6.2 in it sounds kinda cool and different.

 

[k5blazerguy]

Any luck so far?

The first thing I would do is install a clear hose from IP return nipple to return line. This is a super cheap way to diagnose any fuel issues.

You could also install an inline fuel primer to help prime the fuel if you still have a mechanical fuel lift pump. A lot of times that mechanical fuel lift pump quits working. Sometimes it’s best to just take it off, put a delete plate over it, sell the pumps rod for $40 to Bostic Motors and install an electric lift pump instead. It really solves a lot of problems.

Next up would be your heat! Glow plug that is. Best mod is to bypass the Oem stuff and go with a mechanical push button. If the ohms read good on the glow plugs, I wouldn’t waste the money on new Gps.

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I ended up ordering a new lift pump, fuel filter, air filter, glow plugs, glow plug solenoid and J code intake I found on eBay. First time I’m reading all these posts since the fires and thinking about this truck again. Hoping I can get it fired up soon. Electric pump may be a good idea too!

 

[k5blazerguy]

So, replaced the box fuel filter, replaced the glow plug solenoid. Put a momentary switch on it to manually control the plugs, and all new glow plugs,…….
While cranking, I bled the filter and had a steady stream flowing……cracked injector lines and nothin. One of them maybe got wet inside the connector. I can confirm I hear a click when I disconnect and reconnect the pink wire on the IP. Went back to cranking and tryin to bleed one injector at a time. Nothing…
Took the return line off the top of the IP and put my thumb over the fitting to try and build pressure hoping to force fuel out the injector line, nothing. (Fitting was oozing diesel out while cranking)
Next step is to bypass the lift pump with an electrical or just put an electrical after the lift pump to bleed the injector lines without cranking and potentially ruining my starter.
Does it sound like a bad IP? There is some tamper paint on some of the bolts on the housing. Seems like it was gone through at some point before sitting. But who knows.

 

[imiceman44]

So, replaced the box fuel filter, replaced the glow plug solenoid. Put a momentary switch on it to manually control the plugs, and all new glow plugs,…….
While cranking, I bled the filter and had a steady stream flowing……cracked injector lines and nothin. One of them maybe got wet inside the connector. I can confirm I hear a click when I disconnect and reconnect the pink wire on the IP. Went back to cranking and tryin to bleed one injector at a time. Nothing…
Took the return line off the top of the IP and put my thumb over the fitting to try and build pressure hoping to force fuel out the injector line, nothing. (Fitting was oozing diesel out while cranking)
Next step is to bypass the lift pump with an electrical or just put an electrical after the lift pump to bleed the injector lines without cranking and potentially ruining my starter.
Does it sound like a bad IP? There is some tamper paint on some of the bolts on the housing. Seems like it was gone through at some point before sitting. But who knows.

If you fuel is at the IP and it's not pushing fuel to the injectors then it's the problem.
A good one can even suck fuel if the lift pump is not strong enough.