Cold weather churning noise

[JaesRunner]

Hello all! I'm hoping someone could help me locate an odd churning noise in my '87 Runner. Here's some basics: she's running the original 22RE engine and 5-speed manual transmission, has a new master and slave clutch cylinder, new master brake cylinder, all belts were replaced in the last four years, timing chain replaced at 100k (but she has reached the 200k mark), and has a five-year-old water pump. My radiator has a small leak in it, but it does not lose fluid very quickly, so it never runs low. My heater fan is on its last legs and only works on the two highest settings. The a/c crapped out years ago.

So, this winter, we hit temps below 28 degrees for a week straight. A few days into this cold snap, I started up my baby and everything sounded fine (no cold-start problems at all). But once I put her in gear and started moving, a noise like an ice-shaving machine started up in the engine compartment. Whenever I changed gears or took it more than 3k RPM, the churning noise would get louder. I didn't drive very far, about 4 miles, and parked. When I turned off the engine, there was a whirring sound, like a fan winding down. I did my thing and about 20 minutes later I started my runner up and - normal! No funky noises, nothing.

I didn't drive her for the remainder of that cold snap, and when it warmed up I didn't have any issues. But when it gets below freezing, the noises would start up again. At first I thought it was a throwout bearing, but it doesn't seem consistent enough. Also, temperature is the main variable. Any suggestions for where I should start trouble shooting?

I thank you for your help in advance!

 

[crash813]

One thing to consider is also the speedometer cable. Mine gets really noisy the colder it gets. It obviously changes with speed so its hard to tell the difference between it and something tied to the engine.

Past that, I would try to narrow it down between engine or driveline. Is it rpm based, is it tied to the car going/moving, does it change once the car is warmed up? etc.

 

[ed4stoy88]

Could be the power steering pump.

 

[giro]

Lost my original reply.

Was the truck dry when this happened, or could some moisture have frozen, maybe on the wheels/brakes? We had a neighbor who never used her parking brake here in the mountains, and I have had mine be frozen in the engaged position once or twice after driving in snow or slush.

 

[77'911]

You might try disconnecting the speedo cable at the instrument cluster and seeing if the noise goes away. Watch your speed limit, as you might not know how fast your going. Due caution here.
regards

 

[JaesRunner]

[MENTION=99580]crash813[/MENTION], is it RPM based…good question. I want to say that it is because the noise gets louder the higher the RPM, but I also hear it get louder when I engage the clutch (which was why I initially thought throwout). After I park her for a little bit and then go again, the noise disappears, which leads me to believe that when she’s warmed up, everything runs as it should. I don’t have this problem at all from a cold start as long as the temps are above freezing.
[MENTION=12148]giro[/MENTION], she’s parked outside, so there’s definitely a chance moisture got in something, but even on a dry day I’ve heard the noise. I won’t rule that out though, as frost can form on anything around here! I’m sure it’s not the e-brake. Know what that feels like when it’s frozen. >_<
[MENTION=33714]ed4stoy88[/MENTION], wouldn’t I hear a noise when I’m turning the tires as well if it were the steering pump?

@77’911 (and Crash813!) I’ll check on that speedometer cable also. Since the noise happens in any gear, I shouldn’t have a problem testing it out up and down my road without having to do 50!

Thanks for all your suggestions, it’s warmed up considerably now, so I’ll do a little more troubleshooting with your ideas in mind!

 

[JaesRunner]

Woah, sorry for the double post here, I've deleted it! >.<

 

[ed4stoy88]

I have a 86 runner right now that the power steering pump makes a hell of a whirring noise for 3 or 4 min. till it warms up. It's fine after that ,no noise when turning. I've had speedo cable make noise before it was more of a grinding noise than a whirring.

 

[mistersnowman97]

maybe a video of the sound? it may help. but I agree with the above in that it may be the P/S pump. mine did that for a while and one day it just stopped working.

 

[JaesRunner]

Well, (duh) I had to wait until I had a freezing morning before I could troubleshoot! Anyway, new discovery. With the hood up, my hubs was able to pinpoint the noise to my starter. So...is it a starter issue or a flywheel issue?

* * * EDIT * * *

PINPOINTED THE PROBLEM!! :bravo:

Ok, once we determined the noise was coming from the starter (I love having a shade tree mechanic!) we were about to tear into the runner and see if the plunger was stuck. BUT!! When my hubs went to put her in the garage, he noticed that if he held the ignition key too long, it made the same sound, and if he fiddled with the key the noise would stop. So before we prepared for a couple hours of cussing trying to remove the starter, we held off and this morning I tried to replicate the problem. It's another frigid day, and so sure enough she started up and as soon as I pushed in the clutch, the churning noise started up. Then I nudged the key back toward me a bit and the noise stopped.

In my situation, the problem turned out to be the ignition getting stuck in "start" and not returning to "on" when it's cold. I think what's happening is there was still a little bit of current going to the starter and so it's still spinning. When I push in the clutch, the flywheel and starter are colliding (for lack of a better, more technical term) and creating that horrific noise.

So, I think taking my steering column apart is easier than removing my starter!

 

[giro]

Nice detective work! These trucks don't run the starter unless the clutch is pushed in (or the clutch override button is pushed, if available), so that explains that part of it.