startup noise

[john112deere]

'09 Ranger, 4.0 SOHC, +/-33k miles. Sometimes get a pretty loud "grinding" for a second or two on startup.

Truck's done this on rare occasions since new, but it's getting more frequent.

My best guess is A/C compressor clutch, but I don't know.

Initially, it was only if I left the truck for a week or more in high humidity...did it when I got back to the truck Sunday, though, after sitting less than three days- and did it again yesterday afternoon, again sitting about two days.

Had been thinking it only did it when the A/C was left switched on (a practice I try to avoid), but yesterday the HVAC was off.



My concern is that it's gone from a VERY intermittent problem to a somewhat more frequent intermittent problem...but it's still pretty intermittent. And at the rate I put miles on, my warranty will be gone before Thanksgiving.

Thoughts on what it could be?


EDIT: On thinking about it, duration is probably closer to half a second.

 

[blacksnapon]

My first thought is the starter drive not pulling back completely after starting.

 

[john112deere]

That occurred to me after posting this, too...

It kinda sounds like it's coming from high on the front of the engine (like where you'd expect a belt chirp or water pump squeal to come from), but noises can be deceptive- especially lower-tone noises.

 

[dixie_boysles]

its not a rattle right?

 

[john112deere]

Not a rattle, no.

 

[dixie_boysles]

ok, just making sure it wasnt the dreaded timing chain issue

 

[john112deere]

No, I don't think it's that.

But...that warranty's still got a while to go- another year or two, anyway. It's the bumper-to-bumper I'm about to run out of. (And, frankly, with mixed feelings. I like the idea that I don't have to come up with the cash if something breaks...but honestly, dealing with the dealers around here is more hassle than fixing the durn thing myself for most stuff.)

 

[kiwi f150]

My first thought is the starter drive not pulling back completely after starting.

x2