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More weird problems Ford L9000

Welder Dave · 2020-12-09 22:31

The weather was just above freezing so I was able to haul some stock piled clay. Truck started good and the switch I installed for the solenoid valve on the hoist works perfect. The problems I had today were the daytime running lights got dim and eventually went completely out. It was getting dark so was easy to notice. I was also losing air faster than normal. I think the air problem could be cold weather related. The air dryer is a a finned type that I believe is supposed automatically purge itself. The one needle on the air gauge would drop a lot faster than the other one so I think something is maybe sticking. After running for awhile both needles come up to just under 120 PSI so I don't think it's a major issue. It was more of problem trying to drive and put the brakes on to get the sticky clay to dump. Then I had to wait for the pressure to build back up. Also the buzzer was half as loud as normal and didn't shut off until 70 PSI. Is this something to worry about? I don't use the truck much in winter and it's just on my own property. The truck is a 1994 L9000 with a Cummins M11.

Replies25
  1. #1funwithfuel2020-12-09 23:15

    You might have fault in your trailer cord. Common. You have the ancient CR brakemaster, I'm guessing. Not really a dryer, just a place to cool and condense the moisture in the air. Was the dryer popping off rapidly?

  2. #2DB22020-12-09 23:23

    Fords always seemed to have issues with the DRL’s. Might you have an air leak with the brakes applied? Shut off the engine apply the brakes and listen.

  3. #3_Weldman_2020-12-10 00:24

    Ah the infamous air leaks, bottle of soap water might reveal some answers and sounds like you got a live wire grounding out somewhere, surprised a fuse or breaker didn't blow or trip.

  4. #4Welder Dave2020-12-10 01:53

    It's a dump truck but does have trailer wiring and air brake control. I don't think it's fuse related because a fuse would have no lights at all not super dim. I was looking at the lights and they seemed to be too dim (daytime running lights are dimmer but they seemed really dim) then just went out completely. I'll look for some bad wires or a bad ground. Truck volt gauge was low (it always was) but the truck keeps starting and dash lights and other lights work. When I checked a couple years ago it was charging at the batteries so will will check again with a volt meter. The voltage is low sometimes but then comes up just under 12 volts on the gauge in the cab and seems to fluctuate between the 2 positions. Not sure if the ECM controls the charging or a voltage regulator/alternator is acting up? I didn't notice any noise with the air dryer but I had the window up so couldn't hear much. Maybe a bad ground somewhere and it's somehow related to losing the power for the hoist solenoid switch. I wonder if it's just a result for the weird temperature swings we've had that the air system is acting weird? I'll see what it does tomorrow. Supposed to get colder after that. Always had minor air leaks that come and go but was losing air too fast today. Air dryer is similar to this one but may be an older model. Looks like they quit making them a few years ago. Saw one in a 2013 SKF catalogue but nothing recent. NEW SKF 620570 CR Brakemaster Turbo-AC Air Dryer 12 Volt Heater | eBay

  5. #5Tenwheeler2020-12-10 20:41

    Lights sound to me like a bad circuit breaker. Could have a short causing the problem. If you have a light out or unusually dim start looking there. A short can cause your volt gauge to read low depending on how it is wired. Check voltage with a meter at batteries and or alternator. Dryer should purge each time maximum air pressure is reached and no other time. Check air leaks as mentioned. Sounds like you have one at least at times. I would not worry much about the buzzer as long as it is still working.

  6. #6Welder Dave2020-12-10 21:09

    DRL's were working again today and the headlights work so it's not a big concern. The air is leaking at the brakes when you hold the pedal down. I never had anything with air brakes before so don't know if it's cold weather related or just a diaphragm leaking. It supposed to start getting colder now so doubt I'll use the truck much more this winter. Got the clay moved I wanted to. I would have dug more (digging a holding pond) but it was sticking in the box so bad it was counter-productive. I had to take the backhoe over to scrap the clay out. It was packing in the loader bucket too but I got the area cleaned up and on a slope so all the melted snow and water will run into the pond instead of pooling in front of it and being blocked by big pile of clay. Semi-frozen wet sticky clay was like glue.

  7. #7funwithfuel2020-12-10 21:39

    Just remembered. Ford hoods have a tendency to chafe the harness against the radiator. The other thing to look at would be where the harness passes around the steering gearbox. Look closely, I'll bet you see some swollen green wires here or there.

  8. #8Welder Dave2020-12-10 22:04

    I'll have to look. The hood is modified because it's a plow truck with a front mount pump. The grill doesn't tilt forward. There is a harness and electrical plug zip tied right by the grill though.

  9. #9Truck Shop2020-12-11 07:45

    Just install a AD-9 dryer that CR was a POS even when new.

  10. #10Welder Dave2020-12-11 13:20

    The leaking air is somewhere back at the brakes. I didn't have anybody to help me listen to exactly where it's coming from. Could it be related to the colder weather?

  11. #11funwithfuel2020-12-11 15:08

    Does it only leak when the brakes are released? Or does it leak all the time.

  12. #12Jonas3022020-12-11 15:23

    I use a stick to hold down the brake pedal cheaper and queiter than a helper too Probably not cold related if its leaking when you push the pedal could be a worn though line or a diaphragm maybe even a valve it will be pretty obvious when you put a stick on the pedal and slide underneath

  13. #13Welder Dave2020-12-11 15:27

    It only leaks when you apply the brakes. It was frustrating trying to move the truck a little and hit the brakes to get the sticky material out. I'd have to wait for the pressure to build back up if I did it a couple times. I'm guessing one of the brake chambers is leaking but could try a stick on the pedal. I think some chambers had been replaced and others looked old and a little rusty.

  14. #14DMiller2020-12-11 16:26

    Likely a Service Diaphragm failed. Typical.

  15. #15Welder Dave2020-12-11 17:02

    Have read it's often best just to replace the whole brake chamber. There's a truck wrecker not too far away that does mechanical repairs I could take it to. I just don't want them telling me I need a bunch of other stuff done. The truck is just used on my land, I'm not driving it on the road except to get it fixed. I'll find out where the leak is coming from first.

  16. #16DMiller2020-12-11 17:39

    Service side is a Non Issue, Apply brakes vise grip the chamber stud at the base or back the brake adjustment off until the rod extends and holds it in Apply position, then is just the lower clamp and a diaphragm. Under a Maxi is a tad different.

  17. #17Welder Dave2020-12-11 18:15

    I've never done anything with air brakes but know they can be dangerous if you don't know what you're doing. I'll see if the weather warms up again and try to pinpoint where the leak is coming from. It sounds like a simple repair for someone who's done it before.

  18. #18suladas2020-12-11 18:24

    Replacing a brake pod is super easy, if it's leaking I would just scrap it and replace, they are like $45. Not dangerous to replace one, it's only dangerous if you try to open them up. This time of year if i'm hauling clay, I coat the inside of the box in used oil to stop it from sticking.

  19. #19Truck Shop2020-12-11 18:52

    Just make sure you cut the stem the right length.

  20. #20Jonas3022020-12-11 20:15

    It's about an hour easier to replace a diagram and they are like $2.50 though i splurge for a new band usually so like $8 total and 10 mins time not all cans should be replaced and not all should be fixed I've replaced around 60 of them this summer in our little fleet piggybacked about as many and put diaphragms in a bunch too

  21. #21Welder Dave2020-12-12 00:53

    I'll have to see if we get some warmer weather. It's not a big priority right now but does need to get fixed. If it's one of the rusty pods, maybe it's better to just replace the whole thing? I know some of the rubber plugs for where the cage bolt goes are missing. That probably doesn't help anything.

  22. #22suladas2020-12-12 01:57

    Honestly never knew it was that easy to open them up and replace. Of the times i've had shops replace them, not once has one ever mentioned replacing that seal, it's always the can. I can understand if you have that many trucks, but for me 1 truck 1 trailer i'm happy just replacing the can. Also when I tried to cage one of my trailer one once it wouldn't cage because it's so rusty.

  23. #23Truck Shop2020-12-12 07:25

    It wouldn't cage probably because the spring was broke in the park side. I in stall piggybacks.

  24. #24skyking12020-12-13 00:58

    My L9000 is a 92, and it is plumbed on one tank to run shop air into it. If you have a big air compressor, chock the wheels, release the brakes, and do the stick on the pedal to go hunt down your leak. It is nice to have both the quiet and all that air so you can track it down.

  25. #25Welder Dave2020-12-13 01:04

    I have a little compressor so it will run off a generator. I need to wait till the weather warms up. Supposed to be -27C tonight.