Restart procedure post Overhaul. Won't crank.

[MatthewWBailey]

INTRO:
This is a new issue so I'd figure I'd start anew. As most know I've torn apart the truck to replace the oil pump, lots of lines, U-joints, reflash the ECM, reroute exhaust. All is back together (except fluids) but I'm trying to re-torque the TC bolts just as a PM. Since I can only access 3 bolts at a time out of 20, I thought I'd would crank the engine slightly to spin the flywheel.

Problem is, the engine won't crank (of course). This is the first I've tried it since reinstalling the ECM. Batteries are good and the AIH is coming on and off after turning main switch on. I'm using the remote panel but same problem exists when using the dash controls. Starter switch dues not activate the aux relay or starter. Panel shows all the usual lights when power is on but engine is off,.... "check trans", "charging system", "engine oil pressure", "AIH", "low air", "park brake".

I'm going to go see what relays are on, specifically the neutral relay. I assume the ECM is working since the AIH is going on and off normally.

Question: I have no coolant, motor oil or trans fluid in the machine. Will no trans fluid prevent the neutral signal from activating?

 

[Ronmar]

I wouldn't crank it until i get fluids in it. You use a socket on the alternator pulley bolt to roll the engine over for this type maint.

K26 Neutral energizes which powers the coil of K11 alt excite, when you turn on the ignition. K11s coil gets its ground path thru the oil pressure idiot light circuit. K11 provides 24v pin 30-87 when energized, which feeds the start switches which in turn power the aux start solenoid. When the engine starts and the oil pressure ckt opens, K11 de-energizes and provides 24v ign power via pins 30-87A to enable the alternator regulator.

 

[MatthewWBailey]

I wouldn't crank it until i get fluids in it. You use a socket on the alternator pulley bolt to roll the engine over for this type maint.

K26 Neutral energizes which powers the coil of K11 alt excite, when you turn on the ignition. K11s coil gets its ground path thru the oil pressure idiot light circuit. K11 provides 24v pin 30-87 when energized, which feeds the start switches which in turn power the aux start solenoid.

I didn't realize the alt pulley bolt would work for that. I got 6 bolts torque checked by rolling the engine over by hand but that stopped quick once I got some compression. My belt is not on there yet so might as well do it.

 

[Ronmar]

Yea thats the process in the manual for TC bolts and to roll her over for valve adjust…

 

[MatthewWBailey]

Yea thats the process in the manual for TC bolts and to roll her over for valve adjust…

I tried it but the belt slipped too much. No biggie. I used a pair of chain grips around the small boss of the balancer. It turned fine. Got all tightened to 25ftlb. Most were not at torque as you suspected.

I'm assuming the trans has a sensor for fluid level because the neutral relay is off. Pretty definitive. I should've checked the codes damn it. Anyway, I'll buy 60 quarts tomorrow somewhere. I still have to flush it for the ATF changeover. I bit off lots of workload on this one. Maybe too much for my energy level but nearly done now.

 

[GeneralDisorder]

Interesting - I thought our transmissions didn't have the fluid level sensing option. I haven't run across any evidence of it anyway.

 

[MatthewWBailey]

Interesting - I thought our transmissions didn't have the fluid level sensing option. I haven't run across any evidence of it anyway.

The display says N.

 

[GeneralDisorder]

The display says N.

I drive a WTEC IV, but my display says "NN" with ignition on, engine off. And N means neutral which indicates it should be ready to run the starter.

My guess is you have something going on with the crank circuit.... But the transmission at least *thinks* you are good to start. Haven't proven the relays it's responsible for are good or being commanded by the controller but it seems the WTEC thinks everything is good to go.

 

[MatthewWBailey]

I drive a WTEC IV, but my display says "NN" with ignition on, engine off. And N means neutral which indicates it should be ready to run the starter.

My guess is you have something going on with the crank circuit.... But the transmission at least *thinks* you are good to start. Haven't proven the relays it's responsible for are good or being commanded by the controller but it seems the WTEC thinks everything is good to go.

I'll trace it out tomorrow. I ran thru the aux relay wiring since I had all that open, to make sure I didn't dislodge something. But Lots of cables got jostled and pulled-on all around the trans. Maybe I cut something by accident who knows.

 

[Ronmar]

Doesn’t the WTEC 3 keypad only have a single character display(red LED) If it thought it was good to start it should close relay 26 to indicate it was in a valid neutral state. Power for the K26 coil comes directly from the TCU…

 

[MatthewWBailey]

Doesn’t the WTEC 3 keypad only have a single character display(red LED) If it thought it was good to start it should close relay 26 to indicate it was in a valid neutral state. Power for the K26 coil comes directly from the TCU…

This manual says there a fluid level check. The Allison 3070 manual talks about an oil level sensor. Doesn't say if it prohibits anything. It's Not something anyone would ever really experience since no one runs with a drained pan, but it's just interesting. Hypothetically, if you ran over a tree limb and it tore one of those cooler lines and made a good leak, you could drive home, it'd drain out and the next day you'd be empty. Would you expect it to start? If I was out in towel country, I'd like it to start regardless.

 

[GeneralDisorder]

From what I understand the oil level feature is optional and the military didn't opt for it. Maybe it doesn't apply to our extra-deep pan or possibly the controller doesn't have enough GPIO to assign for that function with our AWD and extra 1st gear low range..... IDK but I'm about 99.95% positive we don't have that stuff.

 

[Ronmar]

yea i agree, I think the mil opted out, at least of the functionality. now the sensor may actually be there and used by the TCU internally. Fill it with oil and find out

 

[MatthewWBailey]

yea i agree, I think the mil opted out, at least of the functionality. now the sensor may actually be there and used by the TCU internally. Fill it with oil and find out

Well I double checked again and Both K11 and K26 are off when ignition is on. Based on the circuit, K11 can't energize if K26 is off.

I have to finish the exhaust first so this'll have to wait for that and a fluid refill. I'll test again immediately after refill. Buying 60quarts of atf and 44 of coolant should be a fun shopping trip

 

[Ronmar]

Well I double checked again and Both K11 and K26 are off when ignition is on. Based on the circuit, K11 can't energize if K26 is off.

I have to finish the exhaust first so this'll have to wait for that and a fluid refill. I'll test again immediately after refill. Buying 60quarts of atf and 44 of coolant should be a fun shopping trip

Correct, K26 powers K11 and the oil pressure switch removes K11's ground and de-energizes it when it sees ~15 PSI of oil Pressure. K11 de-energizing shifts 24v ign power from the start circuit to the alternator enable ckt.

I like this ckt design better than the A0, at least if you have an oil pressure sw issue, it will still shut down K11 and bring the alternator online when you shift out of neutral...