Crank pully question

[twoscoops]

I have a 91 TSi and the crank pully has come off/unbolted. My question is will this affect the timing or can it just be bolted back on. I first noticed when the A/C belt jumped and started squealing. I cut the belt and when I pulled on the Alt belt I noticed the pully come up with the belt. Thanks for any help, this thing has been a nightmare so far.

 

[kenamond]

I've only read about working on the timing belt (never changed my own), so I'd ask for a 2nd opinion, but I'm almost positive the pulley coming off wouldn't affect timing...BUT...if things got a bit bound up when things came apart it may have caused the tbelt to jump a tooth. I'd check your timing (make sure the crank, cam and (if you still have your balance shafts) oil pump gears are all timed correctly) to be safe and then install the pulley.

EDIT: There's a great tech article that has all you need to check your timing: http://www.dsmtuners.com/forums/art...l-installing-timing-timing-belt-6bolt-2g.html

 

[Cs4g63]

Are you sure it came unbolted? It is very possible that it seperated.

Picture of a crank pulley that has come apart.

 

[16gpoweredgsx]

I have a 91 TSi and the crank pully has come off/unbolted. My question is will this affect the timing or can it just be bolted back on. I first noticed when the A/C belt jumped and started squealing. I cut the belt and when I pulled on the Alt belt I noticed the pully come up with the belt. Thanks for any help, this thing has been a nightmare so far.

Your timing should be fine, although you will need a new crank pulley, because the hamonic balancer(rubber part) is split or cracking and will keep throwing your belts off, just get a new pulley and belts and you should be good to go.

 

[ILLegit420aT]

Your timing should be fine, although you will need a new crank pulley, because the hamonic balancer(rubber part) is split or cracking and will keep throwing your belts off, just get a new pulley and belts and you should be good to go.

agreed...i had the same type of issue with my 97 420a throwing ac/ps belts, and a new crank pulley was the end result

 

[Defiant]

This is what is called a "blown harmonic balancer". Repeatedly.

Savor it. No other car in the history of round wheels shits off a harmonic balancer at the rate DSMs do.

 

[twoscoops]

Thanks for the help guys, hopefully this one wont be that bad to fix.

 

[kenamond]

I'd still check you timing. I forget where...maybe the engine mini-rebuild tech article that's a mile long...but whereever it was, the guy mentioned that the tbelt can jump a tooth when the crank pulley fails, and I think he was a mitsu mechanic who'd "been around the block". I think the odds are against that, but I'd still check it out. But that's just the perfectionist and OCD in me.

 

[twoscoops]

Will the underdrive/ unorthodox pullies replace this whole thing or will I need something else besides a new belt?

 

[daren_p]

Will the underdrive/ unorthodox pullies replace this whole thing or will I need something else besides a new belt?

The Unorthodox crank pulley isn't a dampening pulley, if this is a street car thats not something I would choose to run. If your looking for an upgrade to the factory pully, that you won't have to worry about coming apart again, look at the Fluidampr.

 

[twoscoops]

OK last question, will a 2g work on my 91 and does it matter if its turbo or non-turbo (OK 2 questions)

 

[91 Turbo Mitsu]

This is what is called a "blown harmonic balancer". Repeatedly.

Savor it. No other car in the history of round wheels shits off a harmonic balancer at the rate DSMs do.

Nothing to do with the post but that is so true it should be framed.

 

[bmoha2]

My car has a full set of bolt on mods. My 2G has now gone thru three crank pulleys. I just ordered a fluidamper pulley friday. I should have bought something similar two pulleys ago.

 

[gsx951]

The Unorthodox crank pulley isn't a dampening pulley, if this is a street car thats not something I would choose to run. If your looking for an upgrade to the factory pully, that you won't have to worry about coming apart again, look at the Fluidampr.

This is very important to understand. There are a lot of wrong-headed people who will argue this to death but a solid/undamped pulley like the Unorthodox is FTL.

 

[twoscoops]

OK this is the newby forum.......what is FTL

 

[gsx951]

OK this is the newby forum.......what is FTL

"FTL" For The Loss , that is to say, affixing an undamped pulley to the nose of your crank will reduce bearing life and often results in crank failure.

On the OEM pulley, the outer section is attached to the inner hub with a piece of vulcanized rubber. As has been pointed out, the OE part is prone to failure; the rubber section breaks down and the two halves separate. An undamped pulley has no rubber section to dampen rotational vibration in the crank. (the crank actually winds up and then springs back.) These rotational forces, which are great enough to destroy the OEM damper, are left unchecked when you run a unit such as the Unorthodox solid pulley.

ATI - The Dangers of Power Pulleys & Understanding the Harmonic Damper

 

[kenamond]

"FTL" For The Loss , that is to say, affixing an undamped pulley to the nose of your crank will reduce bearing life and often results in crank failure.

On the OEM pulley, the outer section is attached to the inner hub with a piece of vulcanized rubber. As has been pointed out, the OE part is prone to failure; the rubber section breaks down and the two halves separate. An undamped pulley has no rubber section to dampen rotational vibration in the crank. (the crank actually winds up and then springs back.) These rotational forces, which are great enough to destroy the OEM damper, are left unchecked when you run a unit such as the Unorthodox solid pulley.

ATI - The Dangers of Power Pulleys & Understanding the Harmonic Damper

Thanks for that link. I learned something.

I'll have to look at the Fluidampr and see if I should go with that (if it serves its purpose and outlasts the OEM unit) or just go with an OEM replacement.

 

[bmoha2]

you can run an unbalanced pulley like the unorthodox if you have a fully balanced rotating mass. maybe...maybe not. I would think not since the harmonic balancer actually works to dampen the rotational forces dealt upon the crankshaft. My question is...What do supra and skyline dohc motors run for a harmonic balancer? It's a much longer crankshaft.

 

[gsx951]

you can run an unbalanced pulley like the unorthodox if you have a fully balanced rotating mass. maybe...maybe not. I would think not since the harmonic balancer actually works to dampen the rotational forces dealt upon the crankshaft. My question is...What do supra and skyline dohc motors run for a harmonic balancer? It's a much longer crankshaft.

Engine balance has absolutely nothing to do with crank harmonics. Follow the link that I posted above.

 

[kenamond]

Correct me if I'm wrong, but the one-liner synopsis of that article is that the harmonic balancer damps out tortional ringing of the crankshaft.