so after 3 years of trying to get my hands on a k5la my buddy found an old one in a junk pile beside his house and gave it to me… only problem is, sometimes all the bells will sound and sometimes its only the smallest one…and that was around 120 psi from a portable air tank… i thought maybe they just needed to be cleaned on the inside but i could use some advice… any help??
You may need to rebuild the internals. PM Curt S. I’m pretty sure he sells the diaphragms for those.
Hornblasters sells them as well.
ok thanks ill look into doing that… but also i took the cap off the one that works and its actually looks greased up while all the others and dry… think maybe i just need to put some sort of grease or anything in there? opinions?
Zero anything should be in there. Please take pics of everything. We will be able to help figure this out. The reasons there not sounding can be numerous. I rebuild these things for a living so I can direct you to what you need to do. Pics are really whats needed.
If they were outside for years unused they may be in bad shape.
k here’s some pics… all the internals look just like the one i have showing…and its definitely been weathered…
What would you take for them? 
If it were me, I would have them media blasted first. Then you can paint them in your garage real cheap. But I would recommend getting new diaphragms and seals in them.
Ugh. That is a fixer upper.
Use a good penetrating oil and soak every bolt. Those older bolts are prone to breaking even on horns that are maintained.
You can try using a red scotch brite on the surfaces where the diaphrams go. Bell and back cap sides. It looks you may have pitting in there. So they may need media blasting or remachined.
As far as asethics of the horn i wouldnt do anything but media blast them. Even then you wont have a perfect horn as there looks like there is alot of pitting.
I am willing to bet the diaphrams are shot too.
To have a proper sounding horn you gonna have at least 200 dollars into this thing with parts. If you dont media blast them youll have a ton of horns into them to repaint them properly.
To have a restored one in perfect working order ready to be painted your looking at 300-350.
Nothing is free.
Get some pics with all the diaphragms shown, both sides, pics of all bells inside the kettle, and pics of every back cap showing the inside. Also need your plans for the horn. Since I do this every day I can accurately tell you what you’ll need, time needed, and costs vs you or myself or someone else fixing it.
well for my plans, i’ve always wanted a nathan to put on my truck… just never had the money to buy one…i can get a restored k3 off of ebay for around 400 dollars. i payed 100 for this one… how much do you think its worth with the condition its in? and ill be sure to post some pics tomorrow
What I have seen tops, about 350.00.
Corrision really kills the bells worth, regardless if the diaphragms are good. If all the bell nozzles need machining and new diaphragms and seals are needed your looking at 400-500, if everything needs work or replacing.
New diaphragms and seals are 35 for used, 45 for new ones for each bell. Machining the nozzles is about 40 dollars each bell. Media blasting a k5 starts at 150.00. Broken bolts add to the cost as well.
It can get very costly to fix. Not trying to scare Im just letting you what it can cost given the few pics I have seen.
The rubber cushions can prob be saved, a few of the diaphragms may be saved as well. Without pics I cant give you an exact price to fix it.
You dont see this often as most horns arent left outside.
alright here’s some more pics… lemme know if you need to see anything else in particular…and you said you rebuild these for a living right? i was thinkin maybe shippin this thing to you if you was up for it…i just want the thing to work…
more pics
Diaphragms look like some can be re-used if not beveled or warped.
Rubber cushions can usually be restored. Not always in a case like this. They sometimes will have parts of the silicone stick to the diaphragms. If you can get them out of the back cap you can try to pry them apart. Blow compressed air in the center hole of the back cap.
Hardware is junk.
Diffuser disks are ok just need cleaning.
Now the bells, 2 of them look to need possible re machining. 3 look decent for just a blasting. All bells will have pitting on them, but it wont matter since its under the truck. The extent of how deep cant be determined until there blasted. But its only cosmetic.
Your basically looking at new hardware, possible 10 new or used disks, media blasting everything, and possible remachining of 2 of the bells. If the bells need major work they can be fixed. Its about a 2 week turn-around, or if you dont want to wait I can switch them out for with the same type of bell. Just need to pay the cost of me fixing them.
You will have pics of everything before any work is done to better explain whats needed and your options.
Shoot me an email. MrLed@Comcast.net
Or call me Tommorow from 8am to 8pm EST.
Curt S. 570-499-1821