Noisey engine accessories?

[andymac0035]

What you are saying makes sense, but my car is doing that with the compressor "off" too. I always shut my heater (or A/C) off before I shut my car off. So it should still be off on start-up right? Or maybe I'm just missing the obvious (wouldn't be the 1st time).

[gadget73]

no, removing the belt won't affect anything or cook the converters.

See if its not the belt tensioner before assuming its the AC though. Its right underneath, and they go bad too. It was one of the first things I replaced on my car actually, mine was making a high pitch squeaking noise. The one on the truck went out with the typical grindy bearing noise, same on the Mark VII.

[andymac0035]

Thanks, I'll make sure I check that pulley as well.

On the A/C compressor......I noticed tonight that I couldn't get it to come on at all.
When it didn't come on with the defrost setting I tried max A/C, full fan and still nothing.
So I'm going to see if unplugging the harness gets rid of the noise 1st. If not, I'll be checking that idler pulley while I'm taking the belt off.

[merc91]

yeh i didn't have my compressor on at the time she blew but for some reason she still grabed, i took off the harness after i was on the side of the road and it was alright until i could get a junkyard compressor, thats still unplugged, just using it for the pully basically.

good luck

[andymac0035]

I tried unplugging the A/C compressor today. Same shit, noisey on cold start-up.
Then I plugged it back in and messed with the heater controls to see if I could get it to grab. Finally did with max A/C (cold full fan). When it grabbed it all but stalled the engine. The the idle recovered and smoothed out. But, the compessor was kicking on and off. I thought the compressor was supposed to run constantly on max A/C (cold full fan).

After that it quited down, but by that time it may have been running long enough to quiet down on it's own. We'll see what happens when I get off work tonight.

Next step will be pulling the belt and checking that idler pully.

EDIT-
I forgot to mention, that when I got this car the A/C did not work. There was no R-12 in it....well the tiniest pffffffttttttt came out the nozzle-thing, but then just compressed air after that. I used an R-134a conv. kit.....but that's all......no new hoses/o-rings/and-whatever-that black cylinder-thing-is (evavorator/accumulator?....ehh I dunno). It took all 3 cans to fill it too. The cans came pre-mixed with ester oil in them BTW.

[gadget73]

If the compressor won't stay on, its probably low on charge. If you didn't replace any of the seals, the 134 went out the same leak as the R12 did. Not likely related to this noise though. When they seize, they just seize without warning. I've never noticed one making abnormal noises until the smoke starts to come out from under the hood. It also depends if its the compressor or the clutch bearing that fails. The bearings make noise, and unplugging them won't help. If the compressor itself seizes, it will spin fine as long as you don't try to engage the clutch. Pull the belt and spin the pullies, you'll find the noise source.

[andymac0035]

I pulled the belt today. Started the car and all was quiet. Took it for a short drive and all was still quiet. Put the belt back on.....didn't make the noise then either. It warmed up some today (but it's still cold) so that might have something to do with it. Or the fact that the engine was now warmed up.

The compessor was working when I put the belt back on too. On newer cars I know that below a set temp (usually 50 deg F) the compressor doesn't come on. I learned about this when I bought a 1999 ranger xlt. Would my 91' be like this as well?

I spun all the pullies before I started the engine. None of them felt sloppy. The idler made no noise. The A/C made a slight noise, and the smog pump made a little noise. None really sounded like a bearing noise, I dunno what I'm listening for since I'm sure the sound would be different spinning it by hand right?

The smog pump was the "noisiest" but it didn't sound like what I heard before.
It's a pump so there should be some resistance right?

Will the smog pump and/or A/C pump off of a lincoln Mark VII work?
Or are they reverse rotation like thier water pump is?

[gadget73]

Its not temperature regulated, just pressure.

Smog pump ought to be the same, but unless you have really anal inspection where its required I wouldn't bother. AC compressor I think is different, probably mostly the mounts. Might be wrong on that tho.

I'd mostly be feeling for the bearing grinding or feeling otherwise rough. If you've ever spun a bad bearing by hand, you'll know it. Good bearings rotate smooth, bad ones bind, grind, or just feel wierd.

[andymac0035]

Its not temperature regulated, just pressure.

Not sure I understand how that works, but if it's not a temp. thing then I guess the outside temp. isn't a factor. I know when I bought that ranger (new in 99) it said (in the owners manual) that certain heater funtions would only cause the compressor to run if it was more than 50 F outside. Something to do with defogging the windshield by drying the air.

All 3 pullies spin freely. There is an odd feel to the smog pump, but I figured that was because it's supposed to pump stuff and the engine was off. It doesn't grind. I suppose, since you said it wouldn't hurt anything I could just take that belt back off for a while and see what happens.

Reason I was so suspicious of the A/C pump was because I suspect that it's been without refrigerant for a long time. I figure there would be more wear on that bearing sense the clutch probably hadn't kicked on it quite some time. Also is a bit damp (as in oily) around the clutch assy too.

[gadget73]

There is a low pressure switch on the drier. If the pressure gets too low, it shuts the compressor off. Thats about the long and short of it. Pressure is linked to temperature, but its also linked to charge so either condition will cycle the compressor, but there is no outside temperature sensor that keeps the compressor from running.

Oil is probably the compressor front seal leaking. The bearing will be permanently lubed with grease. Or, more accurately, its permanently lubed until its no longer lubed. Freewheeling doesn't really cause excessive wear. Most cars don't engage the ac compressor for at least half the year. Whether or not there is any refrigerant in there has little bearing on whether the clutch bearing is going to fail.

[andymac0035]

Thanks for the answers, I'm starting to understand things a lot better now.

Do you think it was just a coincidence that this all started happening when it starting getting really cold and frosty up here?

[gadget73]

grease stiffens up in the cold. Belts also shrink, and become harder. Probably not coincidence. At work, I have problems with things failing when it gets hot, and when it gets cold. Drastic temperature changes screw with things.

[andymac0035]

Well, I took that belt off again before I left for work today (geez I'm working a lot of O/T) (No weekend for me). That noise was gone. All quiet at start-up when I left to come home tonight as well. So I know for sure it's one of those pullies. I spun them by hand again. I'm starting to think it might be the smog pump (it felt a bit odd). Like maybe the bearing is just starting to get "dry". Ehh, I don't really know, I'm guessing. The sound (with the belt hooked up) kind of reminds me of what a small electric motor sounds like when it's burning out.

So I figure I'll grab the smog pump off the mark vii parts car as I'm sure the guy getting the motor isn't going to use it anyways. I figure if I swap it onto my car it'll tell me where the noise was (or wasn't) from.

I'll admit it, I'm anal....my gut instinct is to either have a complete functional sytem or completely de-smog the car. (which is "kind of" legal here). But I believe you when you say I'm not hurting anything just running without that belt. And also it made my exhaust a touch louder.....always a plus. As is the extra power ditching the belt frees up.

Out of curiousity......so all that pump does is pump air into the cats?
What's so important (to the EPA) about that?
And why don't I need to care if it runs or not?

[gadget73]

The smog pump actually does three things. On startup, it pumps air to the back of the heads so that there is actually flame coming out of the manifolds into the converters. THis is so they warm up faster since most of the emissions a car produces are before its warmed up. After a couple minutes, it stops doing that and pumps some air to the rear converters. Mostly thats for temperature regulation. The rest of the air just dumps to atmosphere. The little venturi on the side of the smog pump also produces a bit of vacuum for the cruise control so the cruise works under heavy engine load.

Truthfully, I've never had problems with my cruise control without the smog pump being present. I also have no problems passing inspection, either with the old original converters or with my current exhaust.

[Tiggie]

Smog Pump noise... mmmm... I ditched mine and the motor sounds like a real motor instead of buzzing vacuum. All of the smog pumps I have ever had feel weird as compared to a correctly functioning A/C clutch or any other engine assessory.

Without the smog pump, mine cuts off cruise during extended hill climbs (cruise still functions 95% of the time). Still running the factory cats (all four) and I've never had a problem with mine.

The only time you need to care is if you need it for inspection purposes. It really doesn't free up much power unless yours is bad (in which case it will soon lock up and need attention anyway).