02 WRX Sedan: just found out today that my AC belt slid off, the plastic pulley that tensions the belt literally melted and slit open my timing belt casing. don't know how long i've been running my car with that problem! guess i found the rattling noise. This happened after I installed stage1 clutch 12# flywheel. I was just wondering how the hell that plastic pulley melted? it melted off and was sitting near my fan! the melted plastic, which hardened, stuck on the ac belt and cut open the timing belt case till it finally came off. I also installed Perrin lighten crank pulley, unorthodox lighten pulley set (not underdrive), grimmspeed manual boost, boosting at 16 psi (to be safe), turboxs hybrid bov, but didn't notice the rattlin sound till after 100 miles or so after the stage1 clutch. Could it be that i need to switch to a metal pulley? if there is one? or is something wrong that caused it to melt? Since winter, I've been pushing my car very hard, showing off to trucks and other stupid cars that thought my car was a 2wheel drive import of some sort. ha! down shifting on tight turns and hitting 90 on 3rd gr, burning trucks & cars on the unplowed side of the street etc.....
Had same thing happen to me u will need to replace the pully if not the whole assembly and the front portion of ur timing cover. The plastic pulley works fine the bearing in it either worked loose or u didn't tighten the bolt that fastens it to the rest of the assembly tight enough after putting ur belts back on
check to see if you A/C pump seized.. or maybe that pulley itself seized, overheated and melted.. really teh only reason why
Not the whole assembly Bilknutz, just the plastic pulley. It has little to do with the plastic pulley being bad, but more of the bearing just wearing out. That little sucker spins pretty fast, and the bearing can't hold out forever.
hmmm...it was on pretty tight, boy if i had the time to download the pix, that thing melted off pretty good! sucks that you're right about having to change timing cover, look at it, and a few things have to come off to get to it. maybe i'll find a cheap and reliable way to keep the dust out of it for now.
Driftin240, i think you're logic is logical, i was doing some research and found an autowarehouse parts online, and they sell a couple of stronger material for the accessory idler tensioning pulley, as i found out what it is actually called. but next to one of the pulley was a sale statement claiming that it is made of stronger material to handle sports tuned, and not fail or melt like oem plastic ones. something like that. correct me if i'm wrong, cause i never heard anyone having to switch that pulley when their wrx put out more power than mine. also found out that that belt is for the ac and water pump? what does the water pump do? dumb Q's, car seem to be running fine since i don't need no ac right now...ha ha, but the water pump? Maybe I'll go ahead and order the pulley for $36 and really watch my REDLINE!!! these 02 freaking redline on 1st&2nd gear quick as hell!! VMMM, VMMM, VMMMMMMMMMM!!!
A sports tuned pulley? LOL It's just an Air Conditioning Belt Tensioner, how much power does your A/C system make??:laugh: It's not the pulleys fualt, it's the bearing. Unless they are using a wider bearing, which is unlikely due to space, then you can't make too much of an improvement. The water pump is driven by the Timing belt, so stop reading on whatever site you are reading on. The water pump circulates coolant through your engine, so it's quite necessary. Play carefully young one, otherwise you will be needing more than the $36 pulley...:eek3:
I just went through my timing belt an replaced every other idler on the front of the engine other than that one. About two weeks after the service I was driving my car home from the airport after it sat there for a week. I noticed a whine or squeal almost immediatly. I was able to trace the noise back to the tensioner, being that it was the weekend I ended up having to put a part from o-reallly's (it was a metal part from gates). I am sure that if I had left that pully on much longer it would have melted after the bearing failed. I guess my point would be that it wasn't the plastic that failed, it was the bearing, there was no design flaw with the original other than [parts not lasting forever
ha ha, you're right, i need to play carefully. but with the set up that i have, maybe from the lighter flywheel and lighter pulleys spinning that sucker faster than it's used to like you say that pulley spins pretty fast, but would that lighten flywheel really make the crankpulley(which is lighter too) spin faster causing the pully to spin very fast and melt? since by looking at it, the pulley sits around a metal piece that connects to the bolt that you loosen up to tension the belt. now does the pulley spin around the metal piece or does the whole thing spins? should of look at it closer. but the middle of the pulley in contact with the metal connector is what melted. dumb Q's again, now bearing you mean the part where the belt sits on? the grove of the pulley? i figure due to what you say on space, cause yes it's pretty tight there.
f&egg! i just kept on thinking that it was my stage one breaking in, did sound like squal like water pump failing to a ticking ratling sound, but never thought of checking that pulley, anymore problem after the install?
1. The only way your crankshaft pulley can spin faster, is by the RPM's going higher. Unless you have a built engine that can rev higher than 7,000, you really cant spin it faster. It melted because the bearing failed. 2. The center of the pulley is where the bearing is. It doesn't come serperately, it is part of the pulley. The very center of the pulley is the bolt that holds the pulley to the adjuster and bracket. 3. The belt rides on the plastic pulley. The plastic pulley has a bearing pressed into the center.
Hopefully this helps you understand. This is the parts diagram for an Impreza A/C tensioner setup and the A/C Compressor. I singled out the main parts of the tensioner. All you should need to take care of the broken parts are the center bolt, the pulley, and maybe the adjuster.
thanks alot, I was able to pound the bolt out from the bearing. Suby bro's are the best! look for a black buggeye with perrin stickers on the back, perrin&Grimmspeed on back side windows, sti wings&hood scoop, black out taillights
Haha don't worry about it... Late night post... Looks like Brian has you covered. Good luck with the repair!
