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What is your opinion on this (a little long winded, but stay with me):
It relates to a tandem axle truck (not MV), but you guys know everything!)
Cummins ISM 400 (I think) engine, equipped with emergency shutoff (a spring-loaded flap in the air intake that can be triggered to snap shut).
Going on the highway at about 55 mph, the shutoff triggered itself (long story short; it took me a while to figure that out). Lights, buzzers, the whole shebang; stranded.
Re-set the shutoff flap and attempted to start; cranking sounded like battery was dying (I know for a fact that the batteries are 100%). I thought "uh oh"...then she caught, started with severe knocking, belching smoke that enveloped the whole truck. Shut off immediately.
Mechanic came, checked, retrieved codes, said "it's nothing" and cranked her up. Rough idle, smoothed out, smoking more than normal.
Turns out, the emergency shutoff does not set the IP to zero when it triggers; the IP keeps injecting fuel, just the air is shut off.
Now....to me that seems that there is so much fuel that gets dumped into the cylinders that the "cranking like the battery is dying" means the starter is pushing through (near) hydrolock!
That would also explain the knocking (piston slapping?) and extreme smoke.
What do you think the consequences of this triggered shutoff are likely to be? Mechanic said to just run her hard to get rid of the smoking (he thinks it is just unburnt fuel in the exhaust).
I have an M35A2 and would be worried about anything from cracked head to bent rods. I would certainly NOT run my truck hard to remedy the issue....
Not an issue on the Cummins? Lower compression?
It relates to a tandem axle truck (not MV), but you guys know everything!)
Cummins ISM 400 (I think) engine, equipped with emergency shutoff (a spring-loaded flap in the air intake that can be triggered to snap shut).
Going on the highway at about 55 mph, the shutoff triggered itself (long story short; it took me a while to figure that out). Lights, buzzers, the whole shebang; stranded.
Re-set the shutoff flap and attempted to start; cranking sounded like battery was dying (I know for a fact that the batteries are 100%). I thought "uh oh"...then she caught, started with severe knocking, belching smoke that enveloped the whole truck. Shut off immediately.
Mechanic came, checked, retrieved codes, said "it's nothing" and cranked her up. Rough idle, smoothed out, smoking more than normal.
Turns out, the emergency shutoff does not set the IP to zero when it triggers; the IP keeps injecting fuel, just the air is shut off.
Now....to me that seems that there is so much fuel that gets dumped into the cylinders that the "cranking like the battery is dying" means the starter is pushing through (near) hydrolock!
That would also explain the knocking (piston slapping?) and extreme smoke.
What do you think the consequences of this triggered shutoff are likely to be? Mechanic said to just run her hard to get rid of the smoking (he thinks it is just unburnt fuel in the exhaust).
I have an M35A2 and would be worried about anything from cracked head to bent rods. I would certainly NOT run my truck hard to remedy the issue....
Not an issue on the Cummins? Lower compression?
