Noobie question-- Trying to get the altenator out, however when I loosed the tensioner nut, it doesn't seem to be offloading any slack from the serpentine belt. Currently I can rotate the tensioner pulley nut with my hand, however the belt is still not loose enough to remove from the pulleys.

This 1990 K2500 was an old plow truck, and has some very rusty bits. I was wondering if it is possible for the tensioner to be rusted in place? I've whacked it lightly with the 18mm wrench, however the Haynes manual implied not to use excessive force. I'm worried if I keep going that the pulley will come off and leave me with an interesting dilemma of refastening it in a tightened state. It seemed to be tensioning / detensioning properly during the first 1/4 of loosening it.

I should mention that while there is some corrosion on the tensioner, it's not nearly as bad as other areas.

Any advice appreciated!

x

that nut on the pulley should be there to remove a worn pulley for replacement. up at the top, on the swivel mounting part should be a square hole for a IIRC 3/8 breaker bar to swing it free. are you doing this?

tesioner should look like this
http://www.rockauto.com/catalog/moreinfo.php?pk=857559

Well, NOW I am. That's why I didn't want to take the thing out all the way--I was worried I was removing the pulley wheel itself, despite doing exactly what Haynes had pictured...

I am never ever buying a Haynes manual for anything older than about 1984 again...

lol.. i was in the same boat when i tried to change my first serp belt, so your not alone.

Hmmm... can't find the square drive for the tension. The top item doesn't have anything otherthan a nut holding it to the bracket. If I can find a camera ill take a picture. The only other option is there is a small hex head bolt sticking out of a slot where I can see the tensioning spring.

I will see if I can tak a picture...

I don't think i've ever used a 3/8 square drive I've always put my wrench on that nut and pushed the tensioner out of the way

ya, i've gotten the belts off with the nut, but needed the drive hole to get it back on

Ok, front we have the following. The tensioner pulley is on the left, the actual tensioner is in the middle, and the alternator is on the right. Note the metal bit in the center of the actual tensioner is not easily to connect tool to rotate it...

http://www.timekill.org/photos/truck/DSC00007.JPG

(http://www.timekill.org/photos/truck/DSC00007.JPG)

From the back, there are no further places to get a tool on the tensioner, other than the nut holding it to it's mount (which, oddly enough, appears to be attached to the alternator...)
http://timekill.org/photos/truck/DSC00008.JPG

(http://www.timekill.org/photos/truck/DSC00008.JPG)
Hope this helps. Due to some DNS issues I can't tell if the pictures will appear correctly or not

ok that one is different. is that a cap in the center of the mount and does it remove? i'm just guessing now

i had dug this up out of the 6.5 forum for you with a link in the thread showing some pics, but i'm not sure if it will help

http://www.dieselplace.com/forum/showthread.php?t=304217&highlight=serpentine

I found the following, that basically is in tune with the Haynes manual. Note he has the socket on the pulley nut and not on the tensioner in Picture #2:

http://www.dieselplace.com/forum/showthread.php?t=370587

This brings me back to my original question if this is the case... ;-)

You gotta carefully use a pry bar..... That whole assembly will pivot to the pass side to loosen the belt.

Update: It moves about 1/16 of the way around with a little more light pounding, however it then abruptly stops. This is with the pulley wheel bolt loose. I am unsure of the total range of motion. In the pictures from the forum link I gave above, the fan shroud and some other items are not installed which make space a little more cramped for me. I think I'm going to either need to remove the tensioner entirely (which should be interesting, given it's still taught) or think of why it's stopping movement after rotating only a bit to the left (as you face the engine from the front).

Any words of wisdom at this point would be nice, such that I'm not taking a pulley off while the tensioner it taught..

That's right put your wrench on the pulley nut and push or pull, don't turn the nut push/pull the pulley. I don't know why you're calling the pivot part the"actual" tensioner. That whole unit is the tensioner, the pulley puts tension on the belt. leave the pivot part alone and just pull on the nut of the pulley.

Just read your last post. retighten the nut. I've used a ratchet but a wrench can slide in easier and give some more leverage. it's like pulling on a compound bow, tough to start but then there's a point where it gets easier. Good luck
P.S. Don't remove the tensioner. It's really not that tough.

ok, looking at your pic. if you tighten the nut (turn clockwise) will it not release the pressure on the belt so you can remove it? i might be looking at it wrong. i've had to pull on belts and pry on tensioner before so i could relieve tension to get belt off to remove a bad tensioner

edit. i see everyone else is helping now too. good.

don't try to remove tensioner with belt on. when it lets go with a few bolt threads left, you'll screw the mounts

That's right put your wrench on the pulley nut and push or pull, don't turn the nut push/pull the pulley

OOOOOhhhh! Makes more sense! Then are you basically pulling against the tension spring? Is there any way to ease off the spring so I'm not having to pull with one hand while removing the belt with the other (and trying not to get finger in between the belt and a pulley? That would suck if I let go of the tensioner arm at that moment...)

. I don't know why you're calling the pivot part the"actual" tensioner. That whole unit is the tensioner, the pulley puts tension on the belt. leave the pivot part alone and just pull on the nut of the pulley.

I was calling the pivot the actual tensioner because it has the spring that creates the tension, for which I assumed the device is named. It made sense to me at least... :rolleyes:

Tighten the bolt back up that you loosened and get a prybar out.

http://i118.photobucket.com/albums/o103/josephhodge/tensioner.jpg

Yeah pry bar work well too. Once you get the tension off it holds pretty easy and the belt should kind of fall away.

A pry bar will shurely slip out[guess how I know]. Use the nut on the pulley.The tensioner should be replaced if over 100,000 miles. They will bind too tight and takeout alternater water pump and all other accessory bearings. I use a dayco-No slack from rockauto. About $40.

Just returned from HF with some pry bars and noticed that the clearance between the pivot and the pulley was quite tight (with most of the force going down, not towards the passenger side) increasing the change of mishap per bk95td's suggestion. I'll give it a shot on prying at the bolt face tomorrow since the Missus came home while I was out...

Thank you everyone for the suggestions, diagrams, and pointers. I really appreciate it! I'll try to post some updates after I get another shot at it. I'll also take a look at getting a replacement tensioner (odo currently around 115000 mi)

I don't think i've ever used a 3/8 square drive I've always put my wrench on that nut and pushed the tensioner out of the way

X2 I never even noticed there being a square hole. I've always used a 16mm socket, ratchet and a piece of pipe to make the ratchet handle longer

The alternator is out! I'm glad I made an impulse buy of a larger pry bar (http://www.harborfreight.com/30-inch-jimmy-bar-92590.html) because it works perfectly. I was not able to get the bar on the end of the nut, however after a few attempts I found that the curve of the pry bar could be used to get the tensioner pulley to move just right if I started on the passenger's side of the radiator hose. As an added bonus, the bar I used is just long enough to rest on the vacuum pump pulley, so I can put the belt on fairly easily once I get the alternator checked and replaced if needed.

http://www.timekill.org/photos/truck/alt-out-2.JPG
(http://www.timekill.org/photos/truck/alt-out-2.JPG)

Thanks!

i just changed a serp belt on the neighbors 1994 6.5. same system on it. i put a wrench on the pulley nut and tried to tighten it(i put a snipe on the wrench for more leverage), and the pulley just moves out of the way.