URGENT I need help with hard starting m1008

My 6.2 is really hard to start cold, I have to spray with wd-40 ( glow plugs are disconnected) to start. after it warms up, it will start on the first crank for several hours. I just finished replacing the lift pump, thought that the problem was a worn out check valve allowing fuel to drain back into the tank, but still having the same problem.

get the glow plugs back in working order. I just used a push button switch on mine. Most 6.2's will not start with out glow plug action when cold due to the "low" 18.5 to 1 comprestion. Now my deuce with 22 to 1 will fire up befor Im able to let go of the starter switch. My flame heater has never worked at it starts at -10 below.

When i said it had cold starting problems, i meant that after it had been sitiing for about 8 hours, it is hard to start. The temp around here right now is averaging about 85 F during the day and about 75 F at night, I shouldn't need the glow plugs at all to start it when its this hot outside.

The glow plug timer cycles every time you start it, not just when it's below 85 F. My kid and I each have 6.2 diesels and they need the glowplugs to start, period. Richard hit it when he said they are a low compression [for a diesel] engine and need warm fuel to fire. If you've recently run the engine, then the fuel in the pump will stay warm for a long time and the engine will start easy. 8 hours is too long, believe me we've been there and done that.

You might want to try replacing the pressure switch on the bottom of the fuel filter. I have heard that these are common to leak air into the fuel system and drain back to the tank. Mine will do something along these lines if it is below 1/8 tank of fuel and parked with the front uphill.

Is the pressure switch a military part or is there a GM part # for it? Also does anyone have a spare glow plug controller and the card that goes under the dash?

It is a military part, and its totally not needed. It is only there for the STE-ICE system, and does nothing but cause trouble otherwise. I have read somewhere about people taking it out and putting some sort of plug in its place.

As for the GP controller, I have no idea... Although I am starting to see $ in rebuilding them!!

I keep telling everyone that the military glowplug system can be problematic and if it starts acting up to replace it with a bypass relay switch "if your cheap" or you can update it with the civy controler and change out the tang connectors for 1/4" glow plugs. I drive my truck everyday, and have for the past month without a single starting issue since!!! sometimes you have to weigh the possibilities of trial and error with military item, or just suck it up and go with something that works. [] my glow plugs come on pretty much every time I turn the key to the on position unless its really hot out and I've been doing alot of stop and go driving. *see the glowplug system update thread for info on what I did and why. My build direction made the civy update the best option for my build up, it may not be the best option for you and you could otherwise do a relay bypass switch. This is all depending on if your glow plugs system is actualy the problem!



PS. the compression ratio on the stock military 6.2 is 22.3 not 18 you can get 19/1 pistons and they work great with a turbo!

I have a manual switch hooked up to the glow plugs, but it doesnt help with the starting problems. I could glow it 5 or 6 cycles and it still wont start any easier( sometimes motor will sound like its trying to start, but wont) Just curious, would starting fluid fire if the starter is not cranking fast enough to ingite the diesel? I know it is a lot more violent of a burn, but would it take less to set it off? How do you have a starter checked, do i have to pull it off the truck and take it in or is there a way to tell how fast its cranking while its in the truck?

:nono: DO NOT USE EITHER IN YOUR 6.2 :nono:


if you need to use something to assist in starting, use pure silicone spary, it works wonders!!



It really sounds like you are losing your prime. For really good answers on the 6.2 go check out www.thedieselplace.com



I can probably give you the #1 answer they will suggest... put a clear hose on your return line from your pump. watch it for air, most likely when you are having starting trouble.



the Military Vehicle mailing list at www.mil-veh.org will say before you do anything, replace the fuel pressure switch on the fuel filter base.... It seems that it can cause a bunch of different problems.

CCATLETT1984 said:

I have a manual switch hooked up to the glow plugs, but it doesnt help with the starting problems. I could glow it 5 or 6 cycles and it still wont start any easier( sometimes motor will sound like its trying to start, but wont) Just curious, would starting fluid fire if the starter is not cranking fast enough to ingite the diesel? I know it is a lot more violent of a burn, but would it take less to set it off? How do you have a starter checked, do i have to pull it off the truck and take it in or is there a way to tell how fast its cranking while its in the truck?

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did you check to make sure that you have at least five working glow plugs, some plugs can burn out quiker using a manual switch and sometimes the dropping ressistor "on the fire wall" will cease to funcion and it will let the whole 24 volts through and fry the plugs "remember this a plug doesn't always mushroom at the tip when it burns out" I had the same thing happen to me it sounded like it wanted to catch but it wouldn't, I checked the plugs and found 6 out of the 8 were dead and only one was swollen at the tip

as stated in above posts the ambient temp during the day is around 85F and at night it is only dropping to about 75F (read= hot as hell), i shouldn't need the glow plugs at all at this temp. I am going to try to find the pressure switch and see if replacing it helps, the fliter is stock so i will check and see if the switch is too.

THE 6.2 NEEDS THE PLUGS
I DOVE A HUMMER IN TEXAS (HOTTTT)AND IF YOU DIDN'T WAIT FOR THE LIGHT THEN IT CRANKED AND CRANKED AND IT WAS A NEW TRUCK PICK IT UP IN THE SADUI BRAN NEW

the temperature switch on the glow plugs is set to open when the coolant is 125 degrees or so, "it may be higher than that, but I'm sure its close to that" meaning that it wont stop the plugs from operating unless the switch opens and turns off the glow plug system. This info might be redundant, I'm assuming that you did check the plugs!!

I think I have to agree on the temp.... they dont trigger when the truck has been sitting in the sun all day on a 95 degree day.... I have to figure that would probably equate to about 125 in the engine! HOT STUFF!

My M1010 won't start without the glow plugs if it hasn't been run that day and I am in Mississippi.

If the glow plug relay is not working proplerly it could give you a random sort of problem. Even if you can hear the loud click it is no guarantee that the electrical circut to the glow plugs has been made or made well. When I have had the relays act up, the yellow glow light in the dash acted differently. it would stay on longer of shorter durations than normal for the temp of the day or engine temp. That relay and the plugs themselves are the only things that have been bad on CUCV's that would not start for me. That often maligned circuit card has always worked when installed into a known good truck.

Michael said:

My M1010 won't start without the glow plugs if it hasn't been run that day and I am in Mississippi.

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I got my m1028 from camp shelby hattisburg, mississippi! is that anywhere near you?

I've had a few civi 6.2's and i drive one now with a banks turbo. If the engine coolant temp is below 125 deg f it will not start without the glow plugs. That's because it's a inderect injection diesel. The fuel is sprayed into a prechamber with a half moon shape opening. This improves milage and driveability. You might try gmdiesel.com, it's a fourm like this one but it mainely deals with civi trucks.

another excellent forum is http://www.thedieselplace.com