alternator/power steering belt!

For all you that are mechanically inclined...

The belt on the alternator and the power steering system keeps popping off!

I've tighten all the necessary bolts to keep it in place, tightened the tension, tightened ALL the bolts on the system, yet the belt has "popped out" twice in the past week. Can't take it to the shop yet (this weekend), so short of super gluing the belt on the pulley, what else do i need to check? someone suggested that it might be the harmonic balancer but that system is related to the timing belt, or is it?

thanks in advance.


Josh
1999 Mitsu Eclipse GST

Both the PS and ALT belts are coming off? Mabey the waterpump pullies are not put on the water pump properly. Run the car and see if the water pump pully is wobbling. If not check to see if the belts and pullies are glazed.

Both the PS and ALT belts are coming off? Mabey the waterpump pullies are not put on the water pump properly. Run the car and see if the water pump pully is wobbling. If not check to see if the belts and pullies are glazed.

Actually , kinda sounds like the stock 2-piece crank pulley has gone bad. When the outer ring seperates from the inner ring , you'll get belt problems like that. Mine simply refused to stay on the pulley at all , first time it ever happened to me. If thats the case , you can pull off the d-side inner fender-well and wiggle the crank pulley around by hand and see what it does. Shouldn't be any play at all. If it did seperate , sounds like a good time for a UD-pulley upgrade. I had the Unorthodox SS set , but I don't recommend it to people who only cruise , as the alternator does not charge much at idle. Get the Unorthodox Crank pulley by itself , that should be good enuff. :biggrin:

Ah , crap , I just realized it was a 2G , so I don't know if they still used the 2-piece crank pulley or not on those years. :banghead:

Even if its the crank pully it shouldnt effect the PS belt

Even if its the crank pully it shouldnt effect the PS belt

Yeah , but it would affect the alt belt. I dunno how exactly the 2G's are setup , is it still the same as the 1G for belt arrangement? I gotta look at mine tommorrow and see how the belts run. But just a wobbly water-pump pulley wouldn't affect the alt belt , that I know of. That's why I said crank pulley. :p

I gotta look at mine tommorrow and see how the belts run.

You dont have your engine bay memorized by now?? :shakehead

Like rockin said, the 2 piece damper/pulley is the most common cause for tossing belts. Both gens used them. I wouldnt recomend a non/dampened crank pulley though, as it has been related to crankwalk in other non-dsm cars. If you are tossing the PS belt too, the common link is the water pump pulley. For 2Gs, there was a TSB for a known issue with the alignment of the accessory pulleys. In my case I Can see a visible missalignment of both pulleys, and they both wear into the tbelt cover. Try to line them all up by eye and see if anything is off. Close one eye, and line them up like gun sights, dont be a hoser and half ass it either. ;)

Like rockin said, the 2 piece damper/pulley is the most common cause for tossing belts. Both gens used them. I wouldnt recomend a non/dampened crank pulley though, as it has been related to crankwalk in other non-dsm cars. If you are tossing the PS belt too, the common link is the water pump pulley. For 2Gs, there was a TSB for a known issue with the alignment of the accessory pulleys. In my case I Can see a visible missalignment of both pulleys, and they both wear into the tbelt cover. Try to line them all up by eye and see if anything is off. Close one eye, and line them up like gun sights, dont be a hoser and half ass it either. ;)

Seems to me there are spacers on the 2G (and 1G) pulleys (don't remember which ones) that sometime get forgotten or lost when they are taken off.
On the other hand I gotta disagree with you on the non-dampened UD pulley statement. The 4G63 should be balanced well enough internally from the factory to run without a dampening pulley. So I've been told before , and after running my 92 Eclipse for a year with one , I can beleive it. Now I understand that other cars have problems with those types of pulleys , both Mk3 and MK4 Supra's stick in my mind with regards to that.

I really hate to get back into this discussion again. I cant remember what board it was on. At any rate, the harmonic dsmpener is not there to fix and unbalanced motor. Its there to dampen the HARMONIC, cyclic stresses put on the crank by the individual crankthrows/power strokes. It is not there to dampen vibration. If DSM motors didnt need a harmonic damper for ANY reason the mitsu engineers wouldnt have included it, the cheap bastards. Heres the first link that comes to mind, some good reading:

http://dinancars.com/html/danger_of_power_pulleys.htm


Pleny of people run solid pulleys and never have problems. But this falls under the why take the chance to free up 4 HP category ;)

welp, got word from the mechanic that one of the pulley systems that's connected to the engine has a rubber bushing or whatever-you-call-it that's falling apart. it's circle bushing that prevents the pulley and i guess the rod from causing friction and grinding against each other.
anyway, the rubber is falling apart so there was a lot of 'play' (wobbling) so that caused the belt to 'pop' off.

sheesh, and she only has 40k miles on her too. i wonder what else is falling apart?

Take some time to check for free play in the pulley systems whenever you get your cars on a hydraulic lift.
thanks guys!

Kevin, thats a great article

Exact same think happend to me last week. i was slowing down and suddenly heard a lot of slapping around under the hood. I immediately stopped and found the PS and Alt belts had popped off for no reason, still intact I put them back on and drove home. (I was close to a friends house and just grabbed a 12 mm wrench and that is how I put them back on). The next morning I started it and the alternator belt popped off. Put it back on and made sure everything was good, drove fine for 2 days. Then the alt belt popped off a third time and once back on, the ps belt popped off. I can see a slight wobble in the crank pulley and figured this was to blame. How easy is it to replace?? Good place for an OEM or comparable part?

Thanks!
Steve

Exact same think happend to me last week. i was slowing down and suddenly heard a lot of slapping around under the hood. I immediately stopped and found the PS and Alt belts had popped off for no reason, still intact I put them back on and drove home. (I was close to a friends house and just grabbed a 12 mm wrench and that is how I put them back on). The next morning I started it and the alternator belt popped off. Put it back on and made sure everything was good, drove fine for 2 days. Then the alt belt popped off a third time and once back on, the ps belt popped off. I can see a slight wobble in the crank pulley and figured this was to blame. How easy is it to replace?? Good place for an OEM or comparable part?

Thanks!
Steve


Steve:

I went ahead and let the shop get an OEM.
In retrospect, it's probably something i could've replaced on my own, had i known what to look for.

More than likely, there's some sort of rubber bushing or soemthing that prevents the crank pulley from grinding against the rod.
If you can get it up on a jack, nudge the pulley with your hands on the 12 and 6 o'clock positions and check for play (just like you would your rims to check for your wheel hubs.)

ALso, check to see if the bushings have any sort of wear. That was the culprit for me. The part was about $175 or so, $300 total from the shop.
Hope this helps and good luck!

The damper pulley is 80 bucks from mitsu. No where else to get it. Lifespan is typically 50k to 80k miles, while some cars will go well over 100k before it fails. But thats rare. I think I'm on my 3rd or 4th one at 17k.

Its just a harmonic damper, just like all the old v8s had. Nothing to do with rubbing, rods, cusions, etc. Just absorbs harmonic vibrations in the crack caused by the cyclic application of force to the individual crank throws, in a particular sequence. The article I linked to describes it much better :)

Its easy to replace on your own. There are 4 12mm bolts holding it on. If you are comfortable changing/tensioning the alternator and AC belts, then you will have NO trouble doing this. Just remember the pulley/damper bolts to the crank tbely sprocket, and its aluminum. So the torque is light, about 18 pounds. ;)

Thanks for the info. So what is the part that is actually replaced? All I can see is a double pulley holding the 2 belts. When running there is a slight wobble. In the haynes manual it looks like it is held on by 1 bolt, are there multiple pieces bolted together and then a single bolt to the crank?

thanks
Steve

well ima guess its like any other car in the world lol pull the center bolt then use a puller to take off :) hope that helps have a good 1

Thanks for the info. So what is the part that is actually replaced? All I can see is a double pulley holding the 2 belts. When running there is a slight wobble. In the haynes manual it looks like it is held on by 1 bolt, are there multiple pieces bolted together and then a single bolt to the crank?

thanks
Steve

Nope. Not bolted together. If that were true , for one , you wouldn't have to replace it. No , the 2 pieces (inner and outer) are held together by a thin band of rubber , which is why these things fail over time. Its because the rubber drys out and cracks , and eventually , due to the torque/drag placed on it by the accessories , the outer pulley will seperate from the inner pulley and go a little sideways , or in extreme cases
, come off altogether. There is only one bolt that holds it on. Hopefully you have an impact wrench , or a breaker bar , as that is about all that will take it off.

That one center bolt (actually has a 1/2" square drive reciever) holds on the crank sprocket for the T belt, dont remove that one ;) Remove the 4 smaller ones (12mm or so). Now that I think of it, on one of the setups, not sure if the split is 1g/2g, or 6 bolt/7 bolt, you may have to remove the center bolt because the big washer covers the pulley and wont let it come off after the 4 bols are removed. But I'm not sure. If this is the case, just be careful not to pull the crank tbelt puley away from the block. Thats all we can do, the next step is to get your ass under the car and drive it on ;) Hope that helps.

That one center bolt (actually has a 1/2" square drive reciever) holds on the crank sprocket for the T belt, dont remove that one ;) Remove the 4 smaller ones (12mm or so). Now that I think of it, on one of the setups, not sure if the split is 1g/2g, or 6 bolt/7 bolt, you may have to remove the center bolt because the big washer covers the pulley and wont let it come off after the 4 bols are removed. But I'm not sure. If this is the case, just be careful not to pull the crank tbelt puley away from the block. Thats all we can do, the next step is to get your ass under the car and drive it on ;) Hope that helps.

You got me on that one , I totally spaced that out. Its been over a year since I had my last car all in pieces. IIRC , the center bolt has a washer , but still only holds on the inner T-belt pulley , with the 4 bolts holding on the outer accessory pulley. This is on the 6-bolt car. I'll look at my Galant tommorrow , because even being the NT 4G63 , it should still be the same , being the 6-bolt engine. Thanks , Kevin , I knew I was forgetting something ........ :shakehead