Crank Pulley Strange Problem

[Utah92svx]

I had the belts on my car pop off the other day. While I was replacing them I noticed that the crank pulling was pulling itself into the engine so the other pullys don't line up right. Seems the crank pulley has sunk into the engine about a rib or two for the belts to line up. I have the front belt on but offset on the pulley but cannot get the A/C belt on due to the problem. Has anyone ever seen this problem before, or any advise what could be causing it?

[Trevor]

Originally Posted by Utah92svx

I had the belts on my car pop off the other day. While I was replacing them I noticed that the crank pulling was pulling itself into the engine so the other pullys don't line up right. Seems the crank pulley has sunk into the engine about a rib or two for the belts to line up. I have the front belt on but offset on the pulley but cannot get the A/C belt on due to the problem. Has anyone ever seen this problem before, or any advise what could be causing it?

The OEM crank pulley incorporates a rubber connection which is flexible so as to absorb torsional vibrations in order to protect the crank shaft from high frequency stresses. It would appear that this has become detached and your pulley is therefore running off centre. A replacement pulley is most likely the answer.

[oatmeal]

i have the exact same problem on my svx, the harmonic balancer has separated from the crank pulley (that may account for the incredibly good price i paid for the car and the fact that bluebird isn't talking to me (about the car)). i read about the function of the harmonic balancer on wikipedia, and i tend to agree with it's purpose. the questions i have are:

1. how often does this happen? an oem balancer is $200.-, but if it fails frequently why wouldn't subaru have built a stronger harmonic balancer?

2. if i go with a solid billet crank pulley $172.- and run high rpms, how badly does this hurt the motor?

though i haven't verified it yet, it looks to me like the timing is set by a timing mark on the harmonic balancer. i was all set to "glue" the harmonic balancer together with 680 green loctite retaining compound until i saw the numbers on the timing belt cover. (note: to get 680 green apart after it sets up, you have to use a torch to heat it to above 600 degrees to take it apart).
i still may take this approach after carefully re-aligning the motor a tdc, unless there is a binding reason that this shouldn't be done.

[immortal_suby]

Originally Posted by oatmeal

1. how often does this happen? an oem balancer is $200.-, but if it fails frequently why wouldn't subaru have built a stronger harmonic balancer?

2. if i go with a solid billet crank pulley $172.- and run high rpms, how badly does this hurt the motor?

though i haven't verified it yet, it looks to me like the timing is set by a timing mark on the harmonic balancer. i was all set to "glue" the harmonic balancer together with 680 green loctite retaining compound until i saw the numbers on the timing belt cover. (note: to get 680 green apart after it sets up, you have to use a torch to heat it to above 600 degrees to take it apart).
i still may take this approach after carefully re-aligning the motor a tdc, unless there is a binding reason that this shouldn't be done.

1. It should only happen once - normally we see them separate around 120-150k. Some last longer, some don't.

2. The solid vs. stock debate is long. Do a search here and you will find many threads about it. here's one We have not had a case of any engine failure due to a solid pulley reported. As Trevor stated, The pulley is not a true harmonic balancer,it is only a dampener. $172 is alot for a solid pulley - you should be able to find one closer to $100 if you decide to get a solid one.

A safe bet would be a stock pulley or you can go solid - the choice is yours.


The pulley does nothing with engine timing so don't worry about getting it lined up the same. The slot on it may only be to check engine timing with a light. Since the svx engine control system does not allow timing adjustment then it is pretty much irrelevant. Feel free to try to glue it back together and please let us know how it works out.


We have had some keyways wear out due most likely to improper torque on installation. Make sure to torque properly when you put it back on.

[oatmeal]

thanks for the timely reply and the kindly advice. looks like the solid pulley will win for reliability issues. the thought of blowing apart a rotating object moving at high speeds surrounded by a multitude of expensive oem parts, while appealing, probably isn't for me. that fact that the legacy comes with a solid pulley (boy, i hope i read that right) means that subaru addressed the same problem on later engines. the perrin legacy pulley looks like the right fix, this car is a daily driver, not a stock car; so an underdrive is more trouble than it's worth imo. can't wait to get this thing back on the road.

[kwren]

underdrive pully works great just have to work out the belt size, but many things in life have to be worked out! Get one on ebay and they will tell you the belt size for the svx gost buy it now, 50 bucks