6.2L Wait to start light not coming on

[85 USMC M998]

I forgot to add, that when I installed the new GPC the plugs cycled on.

 

[shor2832]

Good evening! I just joined this site after purchasing a 1992 M998. I have been driving it for the past week or two to my shop and back and love it. This morning, however, the wait to start light did not come on and she wouldn't start in the cold. I didn't try to keep cranking.

I did a quick search on the internet and discovered a couple ideas of what it could be - I got under the dash and saw that it seems to have the upgraded start control box, a KDS CR-2699. Does it make sense that I believe someone upgraded this box? Also - what should my next step be? I think I should disconnect the battery, and pull the plugs on it and make sure there is no corrosion. Then I was going to check the glow plugs with a multimeter, still in the engine, looking for an OHM reading of 1.5-5?

If the KDS box is indeed an upgrade, is there a way to test it to make sure it works? Does this box prevent stacking and ultimately melting my glow plugs?

Any help would be greatly appreciated - I sold my wife on this idea based on the fact that the M998 would be very reliable and rugged. I can hear her yelling at me now when she finds out that its broken down after a week or two! HELP

Thanks in advance,

Sean

 

[Retiredwarhorses]

Good evening! I just joined this site after purchasing a 1992 M998. I have been driving it for the past week or two to my shop and back and love it. This morning, however, the wait to start light did not come on and she wouldn't start in the cold. I didn't try to keep cranking.

I did a quick search on the internet and discovered a couple ideas of what it could be - I got under the dash and saw that it seems to have the upgraded start control box, a KDS CR-2699. Does it make sense that I believe someone upgraded this box? Also - what should my next step be? I think I should disconnect the battery, and pull the plugs on it and make sure there is no corrosion. Then I was going to check the glow plugs with a multimeter, still in the engine, looking for an OHM reading of 1.5-5?

If the KDS box is indeed an upgrade, is there a way to test it to make sure it works? Does this box prevent stacking and ultimately melting my glow plugs?

Any help would be greatly appreciated - I sold my wife on this idea based on the fact that the M998 would be very reliable and rugged. I can hear her yelling at me now when she finds out that its broken down after a week or two! HELP

Thanks in advance,

Sean

A reliable 25yr old military vehicle? I would sell it now...LOL

HMMWV "High maintenance money wasting vehicle"

 

[shor2832]

I get that, just don't tell her!
I like to tinker just as much as anybody else.
Any ideas

 

[85 USMC M998]

Good evening! I just joined this site after purchasing a 1992 M998. I have been driving it for the past week or two to my shop and back and love it. This morning, however, the wait to start light did not come on and she wouldn't start in the cold. I didn't try to keep cranking.

I did a quick search on the internet and discovered a couple ideas of what it could be - I got under the dash and saw that it seems to have the upgraded start control box, a KDS CR-2699. Does it make sense that I believe someone upgraded this box? Also - what should my next step be? I think I should disconnect the battery, and pull the plugs on it and make sure there is no corrosion. Then I was going to check the glow plugs with a multimeter, still in the engine, looking for an OHM reading of 1.5-5?

If the KDS box is indeed an upgrade, is there a way to test it to make sure it works? Does this box prevent stacking and ultimately melting my glow plugs?

Any help would be greatly appreciated - I sold my wife on this idea based on the fact that the M998 would be very reliable and rugged. I can hear her yelling at me now when she finds out that its broken down after a week or two! HELP

Thanks in advance,

Sean

Sean
My KASCAR Non-Swelling Glow Plugs Ohmed out between 2.0 -2.6 Ohms
I have a Yellow Label KDS Box CR2695 and Yellow Band Temp Sending Unit (TSU).
Did your Volt Meter pulse back in forth (indicating that the GP's wire cycling on/off)? From your post it doesnt sound like it.

 

[shor2832]

No the voltmeter did not pulse like it usually does.

 

[StackJ]

After a survey of KDS kits for sale, wow. $350 last year, now seeing $650 to $950. Ugh. Shoulda followed my gut and bought one.

 

[85 USMC M998]

No the voltmeter did not pulse like it usually does.

Rats.
My yellow label makes a clunk noise (solenoid energizing) when I first turn it on. Not sure I’d the Silver does or not, no experience with them.
I guess I would check all other items first (GPs, TSU, Connections & Battery Voltage). I have the ohms values of a good TSU @ 80 DegF if you need it (attached below)

 

[shor2832]

I disconnected batteries, and pulled KDS box. Wiring harness connections look brand new.
took a peak in the box, looks new, no evidence of anything fried.
took each glow plug out and tested on multimeter- all passed at over 1.5 ohms.
next I'm going to reinstall kds box, hook up batteries and test key ignition switch.
Tsu looks new as well.

 

[shor2832]

 

[1 Patriot-of-many]

delete

 

[frank8003]

Me thinks it is time for a "HMMWV won't start" solution sticky.
Or something like that......

View attachment HMMWV S3 HMMWV box.pdf

 

[shor2832]

So after going through disconnecting batteries, removing and inspecting kds box, glow plugs,
TSU, and ignition switch, I put everything back together and she is working. Voltmeter does pulse
for a minute or two like before when I first start. Thanks for the responses.

Vehicle is a 1992 M998, with the 6.5L.

 

[85 USMC M998]

Ahh the case of take it apart and put it back together and everything works. Glad you are back in business.

 

[NormB]

Ahh the case of take it apart and put it back together and everything works. Glad you are back in business.

Those packard connectors and 25 year old dielectric grease aren’t infallible.

I’ve been going through as many connectors as I can this past year one by one cleaning, slathering dielectric grease on the rubber, deoxit on the terminals, reconnecting stuff. I’d really like to get another decade’s use out of the wiring harness.

Glad to hear it’s running.

 

[shor2832]

Thanks- that seems like a good idea.

 

[mdss]

I got one for you guys, see if you can help me solve this problem. Have the nartron smart start (s3) green box with extra diagnostic port. 12480779 tsu in my 998. Was having problems with wait to start. Would just flash when turned on.

Truck cranks and will eventually start with a bunch of white smoke ( gp not heating up ) when cold. No ground problems, starter problems etc. Replaced all gp with brand new the light now stays on 5 sec then goes out. Sometimes the light will stay on 5sec then flash 2 times and go out. Other times it flashes the 10-15 times etc and goes out.

I noticed that when the light comes on it is not cycling the volt meter like it should so clearly the gp are not getting heated up. So, I said okay ******, I took the same smart start green box that I have out of my other 998 and the tsu of which wts light comes on for about 10sec or so cycles correctly on my other 998 and fires up every time in cold weather etc first crank. I installed that box, and the tsu from the other 998 that fires up perfectly and tested gps all is well with gp.

After installing those new ones I turn on ignition and wts light comes on for 5sec then goes out will not cycle gp.... checked all connections and ground everything is good. I even swapped out the temp sensor for good measure. Batteries are brand new voltage is good btw. I am running out of ideas here and this system really is simple so I'm not sure what the deal is? Ideas?

 

[mdss]

So after an immense amount of trouble shooting, turns out the 24v brand new military gp were the problem. They ohmed out just fine but for some reason the s3 did not like those plugs. I got a brand new set of the same exact plugs and everything works fine. What I find interesting is those plugs went through two separate s3 boxes and tsu. Both with same result and not working even though they tested fine. Installed a new set of plugs and works. Theories? Aside from the obvious dud set.

 

[1 Patriot-of-many]

So after an immense amount of trouble shooting, turns out the 24v brand new military gp were the problem. They ohmed out just fine but for some reason the s3 did not like those plugs. I got a brand new set of the same exact plugs and everything works fine. What I find interesting is those plugs went through two separate s3 boxes and tsu. Both with same result and not working even though they tested fine. Installed a new set of plugs and works. Theories? Aside from the obvious dud set.

Chinese made knockoffs? That's really weird.