legacycentral bbs

Okay, here's the situation. For starters, my car is a 93' Legacy L FWD sedan, 197k, manual, 205/60/15 treads. I got back to my car today after hiking and when I turned it over I heard something start knocking real bad so I immediately turned her off. I look under the hood and find that I can wiggle and turn crank case pulley ? (drives the two belts going to the alternator, pumps, compressor, etc.) easily by hand. Clearly this is what was knocking and making such a racket. It seemed that the bolt had just backed itself out some. So I get out my tools (always keep them in the trunk) and I proceede to tighten this guy up. Now I noticed that there were degree markings and what appeard to be a notch that somebody filled in with a weld on the pulley. From what I could tell from my Haynes manual that notch was supposed to line up with the zero degree mark. So I rotated (easily by hand) to where it was lined up and tightened the bolt down. I don't over torque it and then I go and turn over my car to see if it is fixed. I start hearing a racket and then the sound of slipping belts so I turn it off. Now the pulley is no longer straight and is running the belts off. Is this something I can fix in the field or do I need to get it towed back? I can and have done a bit of mechanic work but not much with this stuff. I could really use some help on this and time is an issue unfortunately. Thanks guys.

Lee

Unfortunately, I can't help you with this particular problem, but these threads MIGHT be of use to you:

http://www.bbs.legacycentral.org/viewto ... ank+pulley

http://www.bbs.legacycentral.org/viewto ... ank+pulley

First you need to remove the belts so you can accurately tighten the crank pulley.

I would however take the crank pulley off and see if the keyway & key are damaged/rounded. If it is......you may be in for a costly repair/motor swap. The keyway also serves to keep the gear on the crank which drives the timing belt working properly. If the keyway is rounded and the gear moves, timing will not stay set and all hell breaks loose.

If everything is ok....put the pulley on, and tightening the crank pulley bolt to 120-140 ft/lbs. If you have an auto, stick a breaker bar or something big down the access hole on the pass side of the bell housing on the trans to lock the motor. If you have a MT, put it in gear, have someone stand on the brakes while you tighten things up.

There is no need to worry about timing or anything of that nature. if the key is there, and your pulley slides onto it and doesn't slide around the crank, you are OK. just tghten up the bolt and go.

MK

Thanks for all the help and so quick, tomorrow I will have it towed back to my house and I'll get at it. I'm hoping (keeping fingers crossed big time) that the key way and all is still in good shape. My car has been performing fine (other than leaking a little oil, keep finding oil sitting on top of the block around the water pump but that's another issue for another time) so I'm thinking the timing isn't off and all is well. For a while I'd hear a small knocking sound while driving but turning the heat on would always solve it. Now I know what it was. Do you think has potentially caused much damage? Thanks again guys, I don't want to lose my precious Legacy .

I don't mean to jack this thread, but would the changing on the timing belt require the removal of the pulley?

yes, changing the timing belt would. in his case tho the only belts are the ac and pc/alt belts.

MK

The only way you can get to the timing belt is to remove the pulley and then remove the plastic cover to gain access to the timing belt. At least that is how it shown in my manual.

Lee

If you didn't have the covers you could switch the belt without removing the pulley, just might make it a little harder.

Steve

evolutionmovement wrote:If you didn't have the covers you could switch the belt without removing the pulley, just might make it a little harder.

Steve

No you couldn't......I just did this job last weekend, and there is no bloody way you're going to get the belt out of there without removing the main crank pulley.....plastic covers or no plastic covers!

Plus you wouldn't really be able to see the alignment mark on the crank gear.

http://www.main.experiencetherave.com:8 ... imingbelt/

look at this pic and tell me you're going to get the belt out from behind the pulley?? Not to mention removing the idler pullies.....and you really almost have to have them off to even get the belt off

http://www.main.experiencetherave.com:8 ... P_2728.JPG

I believe when I did it I removed the tensioner (and maybe the pulley) which gave me enough slack to work the belt off one of the cams. I haven't tried putting one back on, but I imagine it may be able be done in reverse. I had to do this on my kitchen engine as the damn pulley wouldn't come off. I broke a cover to do it. Eventually I made a fixture to lock the cams and crank pulleys stationary so I could pop the bolt.

Steve

Keep an eye on that bolt! The previous owner of mine did not, it came slightly loose, the pully came off center, and the threaded end of the bolt snapped off inside the crank. (hence how I traded a rabbit for my turbo leg)

Luckilly most of the half moon groove was still there, but getting a bolt back inside the crank was another story.

Sounds like this crank pulley is an issue that comes up a lot, does damage result from this very often? I love some of the little things on my subie (lights wired to the ingnition, etc.) but sometimes I wonder.

Lee

You wonder about the subaru engine because repair people use the wrong torque spec?

I see your point Ciper and it is valid. A properly engineered engine will work as designed only if it is built per proper specs but it seems that there should be a better way to hold the crank pulley on (our old chevy van had this problem come to think of it so I imagine this is a tried and proven effective method if done right). Guess I still had a little b***hing still in the system due to my car still being out in the national forest .

I cant really imagine a better way to attach it. The sheer strength of that little half moon key has godda be a lot. The weakest part of the assembly would be the groove in the crankshaft, and its probably the hardest metal in the whole car.

Yeah that little key has got to be some beefy stuff. It handles sheer load from the timing belt and crank pulley....

Well it turned out to be worst case senario, or close too. The keyway has been chewed out and overall worn beyond repair so the crankshaft has got to go, though I am certainly open to ideas. How labor intensive is this? My father and I can do a fair bit and are both engineers and pretty good with mechanical stuff, however, if it is going to involve removing the engine I don't know if I want to mess with it. The timing belt looks pretty good and I think was changed out about 10k before I bought it, 15k ago, possible incorrect torques?

Lee

can you replace just the crank sprocket?

well, if its the crank itself thats chewed, your pretty fucked. To replace the crank, is probably one of the most costly, and labor intensive things to do.

However, considering these are non inturupt motors, I can think of a couple gehtto fixes, depending on you tooling situation.

Dowel pins. Drill a hole through the middle of the timing sprocket, through the crankshaft. insert pin. same with the back of the main pulley.

If you cant do that, Ive seen some amazing things done with JB Weld.
I personally have never used it, but I know the stuff dries really hard, and if you cleaned the crank shaft really well, it might just fill in the half moon groove enough, and stick.

Both the pulley itself and the shaft have been worn and damaged. A new pulley would not sit square and true unfortunately. The timing gear looks to be in fine shape though so at least it's one less thing I have to replace.

Lee

is it just the keyway on the crankshaft that is damaged?

MK

This has to be done with a new pulley, the key fitting perfect, is absolutly the most important thing. The pully fits so perfectly on the crankshaft, that that tiny little gap filled by JB Weld, has nowhere to go. It then comes down to the sheer strength of the metalic epoxy, which is strong shit.

again, this is the last resort. Good luck.

The keyway has been sheered out but the shaft itself has also been ground down (small oily bits of fillings can be found in the openings of the timing gear from this). The closer to the timing gear the more wear there is. The very outside of the lip reads .942 in. and the inside is somewhere around .920 in, decreasing linearly. We have a welder and my father and I welded the harmonic balancer back on our old van one time after we discovered the threads had stripped out (we didn't have anything to lose and it got us another few years) but I don't believe I can fill the decrease in diameter and still machine it down properly.

Lee