plode
Member
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- 18
- Location
- South Jersey
So the other day I bought a 1990 M923A2 off of another forum member. It has the Cummins 6CTA 8.3L engine. Engine has a tag says it was rebuilt in 2011.
Been going through it the past two days to see what is wrong with it, and what could use work. I've been trying to follow the TM's but I'm more of a visual person, and the illustrations in the TM's aren't helping me much. I've been searching on here for info as well. I'm sure all of this has been addressed at one time or another, it just is very time consuming having to read through 47 page threads to find what I'm looking for.
What I've found so far wrong with the truck:
1. Coolant leaks. The heater core is leaking, so that is shut off(I saw there is one for a 93 Mustang GT that will fit with some modification to the lid. This is probably what I'll replace it with since it's only $20.
There is also the wye just behind the bottom radiator connection, which seems to have a bit of rust on it, not sure if the leak is coming out of that, or if the hose connections are leaking. I don't have any container suitable(big enough) to drain the coolant into yet, so I haven't messed with it. I'm working on getting a blue 55 gallon plastic barrel that I'm going to cut about 1/2 or so off of to use as a drain pan.
2. Fluid leak. Not sure if it is diesel or something else. There are like 18 million hoses all near it on the frame running to the rear of the truck.
This is looking from under the truck(leak is the pipe with the union, it is directly above the front differential):
This is looking down from above. It is the red/brownish color pipe that goes to a union and connects to a soft line. Again, directly above the front differential.
3. CTIS(of course!). CTIS box blinks all 5 lights. When I click a setting, the valve down on the floor will hiss three times like it's doing something, but then it goes back to blinking all 5 lights. I tried shutting the truck off, restarting it, checked connection to the controller...it must be one of the wheel cylinders. At this point, I'd be happy just disabling the system for now, until I get these other issues sorted out first.
4. Air system.
A. Have a leak in the cab. Apparently the windshield wiper control valve for the passenger side doesn't seal, because it's blowing air out a seal on the wiper motor when the control is in the park position. I tried getting the control valve out today, but there is just so much stuff behind that dash, I can't even get my hands to the back of the valve. I tried pulling the gauge panel out so maybe I could get a better angle on it, but the dash panel won't pull out more then an inch. Not sure what to do there.
It also sounds like the parking brake might be leaking, but a very tiny leak if it is.
B. Transfer case lever is locked down. The button was stuck in, I managed to get it to come back out, but pushing it back in does nothing. I know there is an interlock, but no idea about it.
C. When I shut the truck off, there is air hissing into the intake. I went around with some soapy water and hit all of the lines and connections, only saw two very minor leaks, which I took care of today. I have my dad bringing home fittings from Home Depot so I can connect it to my shop air so I can go around and spray all of the brake chambers without the engine running. The brake pedal also seems very "stiff", but the previous owner says it is normal. Not sure if that is true or not. The only other vehicles I've driven in the past with air brakes were Pierce fire trucks, and their pedals were much more like something you would feel in a normal car, stiffness wise.
When the truck is running, the pressure builds up to 120psi then you hear the thing blow off(more of a long dramatic whine vs what I normally hear on big rigs/fire trucks.)The pressure also drops on both the primary and secondary pretty quick with each brake application. 4 or 5 brake pumps and it's below 90psi and I get the low air alarm.
When the truck is running, something is constantly clicking near the rear axles. I'm guessing this is either something with the CTIS, or ABS.
5. ABS light.
The ABS light was not on when I got it, or for the drive home, but since moving the dash panel out an inch today, the light is on solid. I'm do hear three clicks when I turn the "ignition" switch to the on position.
Another random question- do these trucks have glow plugs? I started the truck up yesterday, it was 14 out. It fired right up but billowed white smoke for a couple of minutes(not coolant, had the diesel smell, not sweet at all). Enough smoke to leave a cloud in my neighborhood
Been going through it the past two days to see what is wrong with it, and what could use work. I've been trying to follow the TM's but I'm more of a visual person, and the illustrations in the TM's aren't helping me much. I've been searching on here for info as well. I'm sure all of this has been addressed at one time or another, it just is very time consuming having to read through 47 page threads to find what I'm looking for.
What I've found so far wrong with the truck:
1. Coolant leaks. The heater core is leaking, so that is shut off(I saw there is one for a 93 Mustang GT that will fit with some modification to the lid. This is probably what I'll replace it with since it's only $20.
There is also the wye just behind the bottom radiator connection, which seems to have a bit of rust on it, not sure if the leak is coming out of that, or if the hose connections are leaking. I don't have any container suitable(big enough) to drain the coolant into yet, so I haven't messed with it. I'm working on getting a blue 55 gallon plastic barrel that I'm going to cut about 1/2 or so off of to use as a drain pan.
2. Fluid leak. Not sure if it is diesel or something else. There are like 18 million hoses all near it on the frame running to the rear of the truck.
This is looking from under the truck(leak is the pipe with the union, it is directly above the front differential):
This is looking down from above. It is the red/brownish color pipe that goes to a union and connects to a soft line. Again, directly above the front differential.
3. CTIS(of course!). CTIS box blinks all 5 lights. When I click a setting, the valve down on the floor will hiss three times like it's doing something, but then it goes back to blinking all 5 lights. I tried shutting the truck off, restarting it, checked connection to the controller...it must be one of the wheel cylinders. At this point, I'd be happy just disabling the system for now, until I get these other issues sorted out first.
4. Air system.
A. Have a leak in the cab. Apparently the windshield wiper control valve for the passenger side doesn't seal, because it's blowing air out a seal on the wiper motor when the control is in the park position. I tried getting the control valve out today, but there is just so much stuff behind that dash, I can't even get my hands to the back of the valve. I tried pulling the gauge panel out so maybe I could get a better angle on it, but the dash panel won't pull out more then an inch. Not sure what to do there.
It also sounds like the parking brake might be leaking, but a very tiny leak if it is.
B. Transfer case lever is locked down. The button was stuck in, I managed to get it to come back out, but pushing it back in does nothing. I know there is an interlock, but no idea about it.
C. When I shut the truck off, there is air hissing into the intake. I went around with some soapy water and hit all of the lines and connections, only saw two very minor leaks, which I took care of today. I have my dad bringing home fittings from Home Depot so I can connect it to my shop air so I can go around and spray all of the brake chambers without the engine running. The brake pedal also seems very "stiff", but the previous owner says it is normal. Not sure if that is true or not. The only other vehicles I've driven in the past with air brakes were Pierce fire trucks, and their pedals were much more like something you would feel in a normal car, stiffness wise.
When the truck is running, the pressure builds up to 120psi then you hear the thing blow off(more of a long dramatic whine vs what I normally hear on big rigs/fire trucks.)The pressure also drops on both the primary and secondary pretty quick with each brake application. 4 or 5 brake pumps and it's below 90psi and I get the low air alarm.
When the truck is running, something is constantly clicking near the rear axles. I'm guessing this is either something with the CTIS, or ABS.
5. ABS light.
The ABS light was not on when I got it, or for the drive home, but since moving the dash panel out an inch today, the light is on solid. I'm do hear three clicks when I turn the "ignition" switch to the on position.
Another random question- do these trucks have glow plugs? I started the truck up yesterday, it was 14 out. It fired right up but billowed white smoke for a couple of minutes(not coolant, had the diesel smell, not sweet at all). Enough smoke to leave a cloud in my neighborhood
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