1994 Ranger 4cyl 2wd.

Had this problem for several months, but it is very bad now, and must be fixed.

When I start the truck, or at low RPM, if I have the lights on and the heater blower running, the drive belt will scream, and the Alt meter will drop.
Most times I can shut the blower off for a few seconds and it will stop, once I am up to RPM driving down the road, I can normally turn it back on.

This morning it started screaming coming to work, and shutting down the blower didn't seem to help, right away. I know this sounds like an Alt problem, with the bearings... The alt is only about a year old, and I got out and checked for a hot bearing this mornaing and could not find one, the pully on the Alt. was cool to the touch, I had driven the truck 30 miles and the belt had been acting up for several minutes, long enough to feel heat I would think. Can the idler pully cause this?

As a side note the heater blower only works on hi, it has been that way the two years I have owned the truck, I don't think they are related.

Also, it doesn't matter if the truck is hot or cold.

 

See if you can find an area on the motor or on the bottom of the hood that has the melted rubber that was slung from the belt. That should lead you to which accessory is the problem. I ad an a/c lock up and this is how I determined it was the a/c.

 

Make sure it's not in defrost or floor/defrost mode. If it is then the AC compressor might be the problem.

Otherwise.. pull the alt and take it to a parts store. They have test stands and don't charge you anything to test it.

Rich

 

No AC on the truck, I should have said that, sorry.

I just took a look at it again, I am still at a loss. I plan to take the Alt off this weekend and have it checked. But I'm really thinking it might be the tensioner arm, it will not budge in either direction, it should have some spring in it?

Not even with a strong arm, I'm thinking it is letting the belt get loose when there is a lot of resistance from the Alt.?

I don't see how the arm comes off?

 

Oh yes.. yes it should take at least 15lbs of TQ to rotate the arm. Pull on a loose part of the belt. If you don't see it move then most likely that's your problem.

Usually they have one bolt right in the center of the rotation hub holding it on. Unscrew it and it ought to fall off.

Rich

 

I had a 94 4cyl and TWICE I found the alternator housing cracked open after I took it off.The crack was between the upper and lower mounting points and could only be seen after taking it off.This led to the armature siezing but I never noticed it getting hot.
Remove the three mounting bolts and swing out far enough to see the backside.You don't have to remove the wires to look at it.
I still haven't figured out why after 8 years of driving it , it just decided to crack.
The replacement alternator lasted one week before it also broke the housing in the same place.

 

Wow, thanks for the info Ken, if it comes down to that I will check the Alt. pretty close.

I'm 99% sure it IS the tensioning arm. After my last post I put a breaker bar along with a cheater pipe and gave it what for, I was able to tighten the belt, just a hair more. That made the screaming go away, even with the heater blower on high. But the tension arm still has no give whatsoever in it, my next step is to replace it.

I called about the part, the parts guy said it should be held in place by one bolt, he said just a metric scocket head. But I recall working with this tension arm last year when I replaced the belt and it seemed like it had a torx head on it? I do recall it would come loose for love nor money, this is not going to be an easy fix, I can see breaking something.
Last night I broke the 3/8 breaker bar, getting the tension arm to move...

Thanks again to everyone for the help, I'll update when I get it "fixed".

 

There is one bolt to hold the tensioner pulley assembly on. I am pretty sure it is a bolt, not torx. You may be thinking of the square hole that is used to release the tension for belt changes.

 

Um... unless your breaker bar is made out of pot metal in a back alley of china.. I'm pretty sure you'd strip the bolt holding the arm in place.

No matter. If you can't move it a little by hand, something is not right.

Rich

 

If you look at the top part of the tensioner you should see a small notch with what looks like a pointer. this will be the round part with the bolt going through into the block.Spray some PB Blaster in that little notch.Wait a few minuites and spray it again.It should work it's way down into the spring after a while and help loosen things up.

 

I will have to get a mirror and look at the bolt holding the tension arm on, I sprayed a little WD on it last time, I'll try the PB on it.

I broke the name brand breaker bar in the 3/8 square hole used to hold the tension arm back for a belt change. That is what I mean when I tell you the tension arm is NOT moving...

 

LOL.. Yeah I'd count on replacing it then.

The guts of those things is simply two cylindrical shapes trapped together with either a rivet or a snap ring. Then there is a clock spring applying tension towards tightening the belt.

Rich