FFRCobra
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- Raleigh, NC
So my horn stopped working that last time I tried it, just the sound of air bleeding when I hit the button but not enough to get the horns to actually trumpet. Solenoid was thumping back and forth each time I hit the button though. Figured it had to be dirt in the trumpets or the air side of the solenoid so I took it all apart and blew out the solenoid with compressed air and did the same with the trumpets. Problem turned out to be the trumpets. Pushing air through the inlet on the horns didn't make any tune from the trumpets but when I covered them one at a time I got enough air pressure to push whatever it was out and got a good air horn blast. Problem solved so I put it all back together.
Hooked up the shop air to the truck and "uh oh. that's the horns starting to wail" As the pressure built up they got louder and louder and by time I yanked the air supply and opened the drain valves my neighbors were looking for shelter expecting an air raid.
Double checked everything. Yep, wire 25 and 26 in the right place. Voltages all check out per TMs at the horn solenoid (wire 26 has 24+V, 25 was "floating"). Forcing ground to wire 25's input on solenoid does nothing, no solenoid click. I don't really know the mechanics of this solenoid but it seems there should be a spring feature that pushes the piston out until ground signal is received on 25 to pull the piston back and let air flow. Nothing is pushing the piston out.
(By the way, the P2P meter readings for wire 25 appear to wrong. At no time would it have 24 volts as indicated. It would be ground or floating depending on horn switch position. Am I reading something wrong?)
So anyway, fix one part and another mysteriously breaks.
I have to get it out of the driveway tomorrow and it won't build air with the horns blasting (nor would I want to drive it that way) so I had to leave the solenoid off the horns and plug the back of it.
So my questions are:
1) Source a working solenoid for the stock horns (anyone have one)? Or...
2) Suggestions on some bigger badder horns that fit the size and stature of a 5 ton? I always thought the stock horn was a bit high pitched and wimpy for such a big truck. They would have to be an easy swap in and not too expensive (say $100 range) to make it worth it to me.
What would you guys do?
Hooked up the shop air to the truck and "uh oh. that's the horns starting to wail" As the pressure built up they got louder and louder and by time I yanked the air supply and opened the drain valves my neighbors were looking for shelter expecting an air raid.
Double checked everything. Yep, wire 25 and 26 in the right place. Voltages all check out per TMs at the horn solenoid (wire 26 has 24+V, 25 was "floating"). Forcing ground to wire 25's input on solenoid does nothing, no solenoid click. I don't really know the mechanics of this solenoid but it seems there should be a spring feature that pushes the piston out until ground signal is received on 25 to pull the piston back and let air flow. Nothing is pushing the piston out.
(By the way, the P2P meter readings for wire 25 appear to wrong. At no time would it have 24 volts as indicated. It would be ground or floating depending on horn switch position. Am I reading something wrong?)
So anyway, fix one part and another mysteriously breaks.
I have to get it out of the driveway tomorrow and it won't build air with the horns blasting (nor would I want to drive it that way) so I had to leave the solenoid off the horns and plug the back of it.
So my questions are:
1) Source a working solenoid for the stock horns (anyone have one)? Or...
2) Suggestions on some bigger badder horns that fit the size and stature of a 5 ton? I always thought the stock horn was a bit high pitched and wimpy for such a big truck. They would have to be an easy swap in and not too expensive (say $100 range) to make it worth it to me.
What would you guys do?
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