A few weeks ago I purchased a 1997 Ranger with the small 4, power steering but no a/c, as my son's first vehicle. It has about 94K miles. I did my first serpentine belt replacement on it yesterday. I will say that getting the long flat serp. belt tool seems really as absolute must and they are not that expensive [$20 bucks or so at most auto supply places]. The question I have pertains to the tensioner. When I pulled it back to get the slack in the belt it was fairly stiff and stayed in the moved position. I put on the new belt and then just moved it back into place. Everything worked fine and the belt is staying in position.

I had anticipated the tensioner would have some spring to it, such that it would automatically return to its normal position, rather than just staying in place. If someone could verify if it is normally "spring-loaded" so to speak I'd appreciate it I am wondering if I am in line for a new tensioner. The other thought is a question of whether given the age of the vehicle the tensioner is stiff because it needs some type of lubrication where it pivots. If so, what type, i.e. perhaps a little spray silicone. If it needs replacement I am wondering if it is a DIY job for a weekend mechanic like myself. I would appreciate any input from other experienced members. Thanks.

 

The belt tensioner is spring loaded and should not stay where you leave it. As you mentioned you might be able to spray some lube on the pivot point and work it back and forth a bit to see if it helps or not. WD-40 would work good to see if anything helps.You could take the belt off so you don't get lube on it and have a greater range of travel while moving it. If no improvement is noted you can replace the tensioner as a unit. Only a couple of bolts hold it in and should be something anyone could do. Check with some of the auto parts stores or maybe you could get one from Ford. Have your son help too.

 

ps. WD40 is just a suggestion as it does penetrate pretty well. You might be able to loosen up the pivot point with this at first, then spray in something else like the silicone you mentioned or something else which will last longer in there.

 

Thanks to both. I'll try the lube with WD 40 first and see if that frees it up but if not I'll replace it. Of course one wonders if it is seized up a little just how much of a knuckle buster it will be to loosen the mounting bolts. But I can handle that with some penetrating oil and a little heat if needed.

I wondered about this also because the tensioner's range of travel did not give as much slack as expected and it was a little bit of a struggle putting on the belt. Thanks again.

 

Sounds like the tensioners spring is broken. As strong as it normally is, if it's rusted up such that the rust is so bad the tensioners spring can't over come it, it's probably time to replace the tensioner assembly.

My tensioner has a 3/8 square drive hole in it's casting, so you can insert a breaker bar or torque wrench in it, to releave belt tension & slip the belt on or off, at the smooth idler pully.

So on replacement, route the belt over all the walled pulleys first, saving the walless, smooth surface, idler pulley for last, to slide the back side of the belt onto. This way you don't have to muscle the tensioner spring very much to slip the belt on or off.

Be careful spraying lubes around the belt or pulleys, as you can cause other problems. Generally silicone should be used carefully around an engine, because if it's ingested by a running engine, it'll take the O2 sensors out, not to mention what it'll do for slipping belts, if it gets on them or the pulleys!!!!!!!! lol

Just some thoughts for consideration.

 

I was going to look at it tonight and see if there is enough clearance to realistically try to free it up at the pivot point with some wd 40, being careful to use the small red straw . I'll skip the silicone for now. I just did replace the belt using a belt tool [essentially a breaker bar with the 3/8 post on it to move the tensioner] and that's how I discovered it was stiff and not springing back. I am very aware that I don't want to get anything near the belt or the pulleys for obvious reasons.

Since I am heading that direction, I am interested if anyone can give me a little more detail about replacing the tensioner, save the r and r of the belt which I know how to do. I've checked on a few sites, including the one which is a sponsor for this forum and a new one is $50-60 bucks. An earlier response said it was a matter of a few bolts. I guess I want to know if it is something that I need to do from under the truck or up top, whether I am going to have some knuckle buster issues with the mounting bolts being seized most likely, and any other tips about replacing the tensioner. Any help from those who have done it before would be appreciated.

 

I went ahead and purchased a new tensioner from the auto parts store. It did not come with a mounting bolt and it appears to be a job you do from underneath. I would really appreciate hearing from someone who has replaced the tensioner before as to whether the mounting bolt is your typical hex to be removed with a socket, is it torx, and should I expect alot of difficulty breaking the bolt loose [i.e. need to use penetrating oil, heat, cheater bar etc.] This is not a job I want to start if I can't finish it since at that point I'd be paying for a tow to the mechanic.

 

I did a quick check on this truck and it does not appear that it mounts using the hole in the tensioner assembly. I am wondering if there is a separate mounting bracket, which may have the same tough bolt issues. Any help appreciated.

 

You might check AutoZones web site for parts replacement details on this model.

I've never had to replace a tensioner & have a 4.0L, so I can't offer up any detailed removal/installation info.

If you bought the part from the likes of AutoZone, ect, may of them have a "loan-a-tool" program, that lets you borrow a job tool you might need, for a refundable deposit.

I'm thinking something like a electric wratcheting impact wrench, if you don't have shop air & air tool, for any stuck fast bolts you may run unto.

If you're going to be turning wrenches on this puppy, why not consider a repair manual or CD, it'll likely pay for itself the first time you use it, mine have over the years. Many like the detail of the CD, I prefer the portability of a book!!!!

Just some more thoughts.

 

Thanks for the information. I have both air impact ratchet and gun but with potentially seized bolts I hesitate because of the risk the head would just break off. I bought the tensioner at Autozone and I am going to check back on the mounting bracket, if that is how it installs, just to see it. I also have the Haynes Ranger manual, but believe it or not, it does not detail the procedure for replacing the tensioner. Specific help from anyone who has done this job would be greatly appreciated.

 

Well you could turn the torque down, if your wrench has that adjustment, or just drop the air pressure to it, so your slowly & more gently pecking away at any stuck fast bolts.

Many times the gentler vibration & a over night soak with rust buster lube, will turn em loose with no damage.

 

Thanks. I certainly agree with your points, I think my preference is to try the hand removal method first, soaking with penetrant etc. as you say. I'm hoping someone who has done this repair can comment on the removal process, where the bolts are, what type they are [i.e. hex/torx] and what I should anticipate.

 

I decided to tackle this tensioner replacement on my own so I will close out this thread by detailing the procedure and clearing up a few misconceptions. I purchased a Dayco replacement at the local auto supply to use. After removal of the serpentine belt I jacked up the truck and went underneath to try to determine how the tensioner is fastened in. There is no mounting bracket. On the Ford OEM tensioner, a 13 mm bolt is recessed in the center of the bottom pivoting mechanism. It was a matter of using that size socket [you have to use a 3/8 wrench with small socket to fit in the recess] on a 3/8 breaker bar to bust it loose. There is no room between the tensioner and the radiator fan to use a gun or even an air ratchet in my judgment. I had to put a small pipe on the breaker bar to get a little more torque to loosen the center bolt.

After that it was a matter of switching to a socket wrench to ratchet out the bolt. It was not rusted. Either Ford in its spec or the last technician who replaced the tensioner did a wise thing and put a small O ring on the end of the bolt to aid in keeping out moisture, so I left that on and put a little petroleum jelly on it to seal some more.

Mounting the new tensioner is easiest from up top. where you can see the rectangular key on the back of the unit that fits in the slot where it mounts. Then it is a matter of simply tightening it up. The Dayco tensioner does not have the recess in the bolt hole as does the Ford OEM so it is a little easier.
Clean your hands well of all the grease and dirt before you reinstall the belt.

The only difficulty I ran into was because the 3/8 key hole in the top pulley, used to pull slack on the tensioner to mount the belt, was positioned differently with the Dayco. On the Ford OEM, there is a flat at the top of the pulley, whereas the knockoff tensioner has a corner at the top of the key hole. You wouldn't think 1/4 turn would make a difference but with a larger serpentine belt tool you run into the air cleaner and then the right fender trying to get enough slack to get the belt on. I solved the problem by switching to my small 3/8 breaker bar, there was a lot more room to move with it and that gives you plenty of slack to slip the belt on easier. It is easiest to slip the belt over the idler pulley last. Let the tensioner go to pull off the slack, clear out your tools and start it up. Let it run 3 minutes or so to make sure all is well and the belt is seated properly.

So for those who need to do this repair some day, that is the procedure. You won't find it in the Haines manual but thankfully it turned out to not be that bad.

 

Good to hear you finally bit the bullet & got it done & apparently without any of those hand wringing problems you envisioned!!!!! lol

Feels good to win one, once & a while doesn't it!!!!

Would be interesting to know if the spring was broken in the old tensioner??

 

Thanks. With an older vehicle you never know. Its starting one of those jobs that if you don't finish it the vehicle is disabled that are the stressful ones, which would be the case if you could not get the serp belt back on, or screwing up the brakes. Call the tow truck. I'm just really surprised this fairly common repair is not in the Haines manual.

I'm fairly certain the spring inside the tensioner is broken. You'd have to pry it apart to look but I'm moving on-saw a fair bit of surface rust when I was under the truck and I plan to scrub the loose stuff off and seal up the metal.