Inside the Horn Compressor

I took apart my horn the other night. I am now certain that I could have just left it in the car and removed the top to oil it. But when I pulled the screws off the top it didnt come loose. And rather than breaking anything I opted to pull it out to have a look. The top just needed a good tap to get it to come free.

I was able to pull the horn out without removing anything else from the car. I just went in beside the spare tire well.

Once I oiled the compressor with pneumatic tool oil and got it all back together, everything worked great!!

Here are some pics of what you will find inside the compressor.


Aaron
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Very nice, thanks for sharing

 

Very interesting...looks a tiny bit like the interior of a Wankel engine in that you have an offset rotor with moving tip seals.

 

My horns quit working immediately after my accident. Had Continental look at 'em and all they required was a little oil.
I was told by the service advisor it periodically requires a drop or two of oil to keep them beeping...

FYI, YMMV...

JIM

 

I just started looking into my non function horn today. I assume my 1989 328's compressor is the same or very similar to yours, looks like it so far. My only access seems to be the wheel off(driver's side) and removing the top wheel well cover.

When I press the horn button it sounds like a motor is running but no horn. Is this indicating the need for oiling only, most likely?

The oiling procedure, looks like removing the metal pieces and oiling in the grooves does it?

Thanks

Jeff

 

where exactly did you place the oil? and how much (drops)?

 

Also, my compressor has two plastic nipples like your with a connection to only on to the horns. What is the other one for, a drain maybe for excess oil to drain?

jeff

 

When I press the horn button I get nothing. On the PPI they figured either the relay or the compressor- any thoughts? Where exactly is the compressor, and does anyone know where the relay is?

...really need to find a service manual for this thing.

 

Mine's under the driver's side front fender just posterior to the pop up lights. I had to remove the wheel and top well cover to get access. The OP seemed to be able to get at it from the spare tire well, I'd guess you could as well. Some car's horns seem to be on the passenger side. Did you check the fuse and relay? Someone with your model will need to chime it to know where but if it's not too difficult, check both sides behind the head lights.

Jeff

 

I was going to edit my post, as I found it just under the passenger side headlight. All is fine on the rear nut, but getting at the front one could be a bit more of a chore. Unless someone has a better suggestion, I think that I am off to get a short 14mm wrench to get in there.

A bit off topic, but does the fuse box cover just hang there by a prayer, or is there some secret to getting it to stay in place?

 

ALCON (All Concerned),

I have an 81 GTSi. The compressor is located on the passengers’ side up front. During the summer I removed the three screws holding the top on the compressor leaving it in place and gently coaxed the top off with a screwdriver and hammer. I do not think it had ever been off before. Tap, tap, tap, off it came. Dry as the Sahara in there. I had a white pad of cotton(?) where your copper matrix is (in your photos) and sitting on top of that was a small copperish colored spring. Added some 3-in-1 oil reassembled leaving everything in place (to include the useless spring). Be careful taking it apart as if you put it back together wrong it will just drone, with No "Beep!!!!!" The blades in the photo sweep INTO the direction of travel. They do not sweep back (like an airplane wing).

Anyway, 3-in-One is too glue-like during the winter. Compressor spins but no "beep" until normal hot temps are achieved. Horn always takes a second to "beep" even when hot. Any suggestions?

V/r,

mwr4440

 

Okay, after getting a stubby 14mm wrench I was able to pull the condenser. It seemed to be moving reasonably freely, but oiled it anyway (the hard part had already been done). I checked for power with the horn depressed using a meter, and nothing. So, it is likely the relay, as the fuse is fine. Any idea where I can find this darn relay? Or, can anyone think of any other reason for the horn to not be working?

 

In mine the relay in with the main relays with the fusebox. Location shown on the relay/fuse cover and in the manual.

Also, an old thread recommended squirting the oil into the intake when running to disperse, therefore no need to remove or take apart. Makes sense to me.

Jeff

 

compressor you can buy from harbour frieght indentical to orig ferr comp $25 fits snug as abug in oem compr bracket + you get 2-3 horns so i ended up using small horn zip tie small horn to comp sweeeetttt...........

 

When you are in the car, push the horn button and listen carefully. You can hear the relay click if it is working. Keep in mind that there are TWO fuses that power the horn. One that supplies power through the horn button to activate the relay, and one to supply the power to the horn through the relay. Check that both fuses are not only good, but the contacts are clean on both the fuse ends and the tabs in the fuseblock. Then check and see if you actually have any power in the fuseblock. They are notorious for melting and malfunctioning. After you discover that the fuseblock is a gigantic piece of **** that is going to require regular maintenance to keep from stranding you, order my replacement set for cheap money and never worry about it again.

Birdman

 

I kind of assumed the relay for the exact reason that you pointed out- you cannot hear it 'click' when you depress the horn.

It was already on my list to pick up your fuseblock, but having only gotten the car a couple of days ago I have not followed up on it yet.

 

Here is my before/after air pump R&R: http://www.ferrarichat.com/forum/showpost.php?p=136030145&postcount=92

Still looking for correct top label.

 

You don't have to remove the vanes to lube the pump. In fact, you don't have to even disassemble it. Just squirt some oil inside the air intake & beep it a couple of times. Then repeat the oil & beep for good measure.

CAUTION: If you do remove one of the vanes, be sure to put it back in exactly the position it cam out of, & facing the same direction. The vane tips wear small grooves in the air pump body, If you put a vane in wrong, it' won't seal properly.

 

Hi. Horn stopped working. Am I correct in assuming that if a) the fuse is fine, and b) there is no sound whatsoever (no click either) from the horn, that it's probably the relay that's gone?

Thanks!

 

That's one possibility (and certainly the easiest thing to try replacing/swapping), but it could still also be the horn switch, the horn switch wiring (inc. the ground connection), or the slip ring in the steering column.

Was it working and suddenly stopped working, or has your horn never worked?

 

Just got the car so I'm not sure. Tried swapping the relayed to no avail. The horn button seems to be in good condition, ground is attached etc.
I'll go for the compressor next. The odd thing, though, is that there's no clicking sound whatsoever, which makes me think it's an issue with power rather than the compressor. Thoughts?

Thanks

JP

 

Yes, if you've got the key "on" and press the horn button, the horn relay should "click" (regardless of the condition of the horn air compressor).
One thing you can do is remove the horn relay from its socket and touch a jumper wire from the female terminal 30 to the female terminal 87 as shown in this jpeg (which simulates a closed horn relay):
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If the horn air compressor spins, then you know you've got some sort of upstream electrical problem in the steering column:
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The older style units have a flip lid on top that says "Put oil here"........the later ones lack this fitting it seems.

As some have pointed out FIAMM horn kits are pretty prevelant in Parts Stores here now, different note combos for different makes.

 

I had a problem with my horn in that the contact in the steering column was worn. The horn worked when the wheel was turned, but not in the straight ahead position. So the next time you go driving, press the horn as you are turning through a corner. If it works in some positions, then you need to take apart the column and fix the contact.

 

Happen to have the SKU for it?

In another thread I noted a vane popped out when I took the lid off. Another slipped out when I was re-assembling. I'm having a dickens of a time getting the vanes situated to create enough pressure again. Not all are extending out of their slots. I'd just assume drop in another compressor at this time. BTW: mine is a three-screw top with no oil hole.


As to the vanes: I can't seem to see wear marks. But I do note one side is smoother than the other. I'm assuming the smooth side is toward the back of the spin from frication.