1994 K75S High-pitched chirping noise when hot?

[Zagando]

Update; Haven't had time to get a new fuel filter yet; will post results once I do and get it installed.... Jeff

[Zagando]

I replaced my 3 year old fuel filter with a new one (Napa 3012 $5.39) today, put some Chevron unleaded in the tank and went for a ten-mile ride around town in the heat of the day.

Not a chirp or squeal to be heard so far; my fingers are crossed that Don was right on target with his diagnosis and that I'm good to go now.

If I am speaking too soon I'll be back to report further but for now I am a happy camper. Thanks Don!

[PGlaves]

Don is almost never wrong.

[deilenberger]

I replaced my 3 year old fuel filter with a new one (Napa 3012 $5.39) today, put some Chevron unleaded in the tank and went for a ten-mile ride around town in the heat of the day.

Not a chirp or squeal to be heard so far; my fingers are crossed that Don was right on target with his diagnosis and that I'm good to go now.

If I am speaking too soon I'll be back to report further but for now I am a happy camper. Thanks Don!

Jeff - !!

Hope that was it. I learned about this from Brian Curry who had a filter plug up - and there was the clue of the chirp noise. It was just unusual enough that I actually remembered it..

Paul, thanks much. Means a lot coming from you.. Hug Voni for me!

[98lee]

Jeff,

If you still have your old filter, you can test it to see how plugged it was by gently blowing through it in the direction of the arrow. If there is ANY resistance, it is dirty. If there is significant resistance, it's plugged up and definitely your problem.

[Zagando]

Thanks again, guys. Although I haven't ridden the bike again yet I really do have a hunch that the problem is solved.

I did blow through the filter afterwards but I think I might have been blowing the wrong way. There wasn't much resistance as I recall but it's only the second time I've ever dealt with a K bike filter thusly. Coincidentally, the same day I was blowing through the filter I had been blowing through some elaborate medical apparatus during a clinical research study of lifelong non-smokers I was participating in to determine my lung capacity!

So even if there was any resistance in the filter I might not have been able to notice it as I was blowing as hard as I could about a dozen times earlier that day.

I'll post a followup next time I go for a decent ride which may be later today; been moved in for a couple of months now and I've hardly begun to discover all the great roads around Albuquerque yet.

[98lee]

You have to blow VERY LIGHTLY.

[Zagando]

Just got back from a 136-mile ride that I made kinda on the spur of the moment. Left at 3:30pm local, got back about 3 hours and 20 minutes later. All two-lane.

For those of you familiar with New Mexico, my route was ABQ-Carnuel-Tijeras-Escobosa-Chilili-Estancia-Tajique-Torreon-Punta de Agua and my "destination" was Quarai Nat'l. Monument. Spent 10 minutes there to take another look at the ruins of the huge old church there (last visit was in 1979) and then I turned arouund and headed home.

It was a gorgeous puffy-white cloud New Mexico summer afternoon and the ride was PERFECT.

Not a whimper, screech or chirrrrrrrp was heard the whole time.

Wow, what a feeling!

[Zagando]

No problems until my next longer ride on August 7th. Near the tail end of the 145-mile loop the chirp popped in a few times for a few seconds.

With a couple more rides around town about a week later the chirp was definitely back and as loud as ever. The last ride it was screeching and warbling like a police whistle (UK) and when I pulled onto the driveway I got off and got down next to the running engine. It was so loud I coudn't tell where it was coming from.

While I already went back to Napa and got another fuel filter to have on standby I am now wondering about another possible culprit that's making the noise.

I noticed that my headlight and aux. lights were dimming a bit at idle like when I was sitting at a stoplight at night; something I haven't noticed before at all. Could the alternator be making all the racket? Maybe the brushes are wearing out or? Another possible clue is the fact that when I went out to the garage to start the bike (was planning on another 125-mile RT to Santa Fe today)---the battery was too dead for the indicator lights to come on. Leads me to believe my alternator hasn't been charging much at all (I also did have a loose battery connection that I discovered and fixed on the 6th, though).

Sorry to be back here with the bad news so soon after what I thought was the fix (and may still be if there was some junk left in the tank after I replaced the fuel filter).

If anyone knows of such a thing as a chirping alternator on a K bike, do let me know. Meanwhile, the battery is being charged with my trickle charger for a good long stretch.

Otherwise, I'll go ahead and replace the filter again despite the very short time it's been installed. Could be another batch of bad gas, too---who knows?

[LOSTBOY]

The noise you describe arrived with smaller fuel pump fitted from 1993. It tends to occur with hot fuel and/or low fuel levels. A Service Bulletin from that era advised us to install a length of submersible fuel line to the return pipe in the tank and to direct the hose over the fuel pump.

[Zagando]

Interesting news; I suppose the extra fuel pouring over the fuel pump would serve to cool and or quiet it down, right?

My best option might be just keep the tank filled up as I know that no K75 fuel pump likes a low level to begin with.

Now I am wondering if this is a telltale sign that my fuel pump is going to need replacing sometime soon. When I took it out to inspect it and replace the in-tank fuel lines/filter and pump sock three years ago the rubber surround was firm and intact---so I don't think it's any kind of goo issue---at least.

Anyone else care to weigh in on this? Perhaps my alternator issue (if it is also going faulty on me) is a coincidence in the first place. Oh, woe is me; almost all of the things my bike needs done (new fork seals, new front wheel bearings, valve adjustment, alternator(?) and fuel pump(?)) are either beyond my limited expertise, capacity or budget these days.

Thanks for the insight, Lost Boy, though; it helps.

[LOSTBOY]

Those pumps were noisy even when the bikes were new. Hence the service bulletin. Installing the hose in the tank is not expensive or terribly difficult.

[Zagando]

I still have some leftover in-tank fuel line from my partial renovation done three years ago. Where, exactly is that point that I would attach it to before positioning the other end over the fuel pump, please?

[42906]

I'de like to see where this run of fuel hose goes too, as I have one of these newer style pumps in a very early K-100RS.

[Zagando]

I filled up the tank again today thinking that the fully submerged fuel pump might behave thus but that notion was quickly dispelled. Still as noisy as ever.

I think that idea of running a fuel line over to the pump is nonsense; yet I will be the first to apologize should/could I be proven wrong. No amount of fuel is going to cool it down enough to be quiet.

I suspect that my pump is beginning to die or wear out---nothing more or nothing less.

Hope that it's not a dangerous situation brewing as I ride around New Mexico in the 90+ degree heat and the pump (or something inside the tank, presumably) chirping like a canary on steroids. How do fuel pumps die?

Curious to hear any stories about other's going south and whether it is usually sudden or long and drawn out.

---Perplexed in ABQ