Aluminum crank pulley question (for those who have done theirs)

[LoboMan7409]

Hey guys my dad and I started to do my crank pulley and we got it off but neither of us knew what this thing was on the inside of the pulley. I dont really know how to describe it but it kind of looks like the slots in a brake rotor so I will post some pics. Please just tell me what it is and what I need it for.

http://i56.photobucket.com/albums/g172/LoboMan7409/DSCI0006.jpg

http://i56.photobucket.com/albums/g172/LoboMan7409/DSCI0005.jpg

http://i56.photobucket.com/albums/g172/LoboMan7409/DSCI0004.jpg

[XtremeGaGt00]

thats your 24x crank sensor...you need it...inless the new one came with it on it...

[LoboMan7409]

that is what my dad thought, do you know where I can pick one of those up because mine got bent.

[notsoaveragej0e]

Is that what they use to get the timing on the engine right?

[XtremeGaGt00]

no not timing issues, just a sensor to tell the pcm what position the engine is at...basically, thats all...id go to a gm dealership and get a new one...

[canadian_racer]

It can cause the your car to lose low end torque mine needs replacing. They are about $80 Canadian usually they are in stock.

[LoboMan7409]

cool thanks guys

[Malaclypse]

It can cause a misfire if the ring is misaligned or starts slipping. Ask me how I know... =(

[canadian_racer]

What code did you get?

[LoboMan7409]

how do you align it? Can I get that part from GM parts direct.com?

[canadian_racer]

You have to take it to a dealership and have a Crank Shaft Position Variance relearn...or something like that. If not the car will still run really rough

[Malaclypse]

What code did you get?

It didn't set a code and I'd already done a CASE learn. The PCM didn't register a misfire because it uses the 24x crank sensor for misfire diagnosis.

It was an issue with the very first of the FFP pullies. The clearences were just a bit loose on the pulley and when heated and cooled enough, the ring slipped on me. Sent it back and Mike at FFP corrected the design and took care of the origional pullies that were bought. Works great now.

[LoboMan7409]

It didn't set a code and I'd already done a CASE learn. The PCM didn't register a misfire because it uses the 24x crank sensor for misfire diagnosis.

It was an issue with the very first of the FFP pullies. The clearences were just a bit loose on the pulley and when heated and cooled enough, the ring slipped on me. Sent it back and Mike at FFP corrected the design and took care of the origional pullies that were bought. Works great now.

so what did you have to do to get it to work?

[Malaclypse]

so what did you have to do to get it to work?

I sent the aftermarket UD pulley back to FFP to be modified to hold the ring properly. Reinstalled the UD pulley when I got it and things were fine after that.

With a bent reluctor ring, though. You need a new pulley w/ ring. I bought a pulley when I did the change just to have a spare.

[LoboMan7409]

what if I didnt get an underdrive pulley I just got the stock size, would just getting a new one of those rings work?

[ihatemygrandamg]

The original ffp pulleys didnt have screws to hold the sensor in place,and it would slip and cause misfires. If yours has screws put some thread locker on them just to be sure they dont move. Also maybe try putting the pulley in the oven for a bit,and use some grease so you dont damage the crank. DO NOT TRY TO POUND IT ON.

Do you have an ffp or an rsm? ffp is a great cheap mod imo

[LoboMan7409]

well my dad has a pulley presser or something but I just dont know what I am going to do about that little ring or what ever

[ihatemygrandamg]

Be very careful installing the ring. When I did mine, I broke my crank positioning sensor lol. Just be really careful doing this, research,and air tools help alot if you have access to them ;)

[LoboMan7409]

well the only thing it what I circled in my pictures, I am at a loss at what to do

[ihatemygrandamg]

Not to offend you but you should def do more research before jumping right into things. Thats what I do before doing any mods/repairs. You learn from other peoples mistakes lol

[canadian_racer]

Thats true. Plus its cheaper lol

[LoboMan7409]

well that is what I did I went and bought the crank seal and the pulley press but I didnt know this was on there sooooo oh well that is why I am asking for help

[ihatemygrandamg]

Well like I said man I was just giving you some advice for next time. If the crank sensor wasnt too bent you could try to fix it very gently, but youll most likely need a new sensor to get the car to run right.

[Malaclypse]

Technically speaking the sensor is mounted to the front cover. The part Lobo is worried about is just the trigger ring for that sensor.

Yeah. New crank pulley is in order and things will be well. $80 new from the dealer. JY probably quite a bit less.

Oh, little bit of advice for switching that reluctor ring over if that's what you're ultimately after. Get a small hole punch and a 8 oz ball peen hammer. Set the pulley on a hard surface with the narrow end down. Gently tap the back lip of the ring and work your way around the pulley to remove it. It might help to heat the pulley in a 200* oven for 15 minutes or so.

Once the ring has been removed from the stock pulley, inspect and make sure none of it is bent. The lip isn't such a big problem, its the part that has all the "windows". So long as that is round you'll be fine. Now install into the new pulley by gently tapping with the same punch. Go at opposite points though and walk the ring down until it seats against the back of the pulley. Then install any screws (if supplied) with threadlocker. Install pulley on vehicle and go to dealership to perform CASE learn.

[ihatemygrandamg]

I never got a case learn,but I never got an ses light.

What I did to get the 24x ring out was put the outer ring of the pulley on 2 blocks of wood, the sensor facing down. Take a screw driver and put something soft on the end and place it on the lip of the ring. Then take a hammer and gently tap it out. Like I said it might be easier to heat it up, just be very careful.

[gectek]

so is the 3400 pulley from ffp stock sized? if not and it is underdrive, then wouldnt you have to worry about alternator output and water pump output, being under driven like that

[ihatemygrandamg]

Ive had no problems with mine and Ive had it on for almost a year. Great mod for the money.

[zhd1000]

so is the 3400 pulley from ffp stock sized? if not and it is underdrive, then wouldnt you have to worry about alternator output and water pump output, being under driven like that

no it's not the stock size.. it's 1.1" smaller and weighs about 3lbs less too.. and on FFPs website the show a voltage reading before and after the pulley and the output dropped from 13.85v to 13.75v..

[AaronGTR]

I never got a case learn,but I never got an ses light.

What I did to get the 24x ring out was put the outer ring of the pulley on 2 blocks of wood, the sensor facing down. Take a screw driver and put something soft on the end and place it on the lip of the ring. Then take a hammer and gently tap it out. Like I said it might be easier to heat it up, just be very careful.


You won't always get an SES light but may still need to do a case learn. I did with mine. Basically any time you change the crank pulley, change the pcm, or do a full write on the pcm, you need to do a case learn to make sure the pcm and sensor are in sync and properly timed.

[LoboMan7409]

Thanks everyone that is exactly what I was looking for. You are all awesome :applause:

[LoboMan7409]

Well I got the pulley on there and lemme tell you it was not fun. And right now I am a little scared because while I was putting it on I heard a loud pop but I guess Ill find out when I get the rest of her together, thanks to everyone for their help

[ihatemygrandamg]

You won't always get an SES light but may still need to do a case learn. I did with mine. Basically any time you change the crank pulley, change the pcm, or do a full write on the pcm, you need to do a case learn to make sure the pcm and sensor are in sync and properly timed.

Hey I never got a case learn after putting in my ffp or my pcm. I guess thats why my car is a pos lol

[Sprucegagt]

You won't always get an SES light but may still need to do a case learn. I did with mine. Basically any time you change the crank pulley, change the pcm, or do a full write on the pcm, you need to do a case learn to make sure the pcm and sensor are in sync and properly timed.

When I changed my ring over, I never had a misfire nor rough idle. Instead it ran nice and smooth. But I made sure my ring was in the exact same position in the FFP pulley as it was in the stock unit.

Also you don't need a CASE learn if you do a full PCM write.

[AaronGTR]

When I changed my ring over, I never had a misfire nor rough idle. Instead it ran nice and smooth. But I made sure my ring was in the exact same position in the FFP pulley as it was in the stock unit.

Also you don't need a CASE learn if you do a full PCM write.


Same here. I didn't have any misfires or rough idle and I made sure the ring was in the exact same position. I still had to do a case learn though since it was switched. My bad on the full write issue. It doesn't "have" to be done... normally when I do a case it's after switching pcm's and I'm doing a full write anyway so I usually am only doing a case after a full pcm write. The rest of the time if you try to do a case and it's been done already it tells you it's not needed.

[aumax]

where did you get your pulley ?
i look everywhere and i cant find one !

PM me

aumax

[AaronGTR]

PFYC carries them. http://www.pfyc.com/c/GAUNDER/Under+the+Hood.html

That's a stock diameter (non-under drive) light weight aluminum pulley. The company who actually makes it was called RSM (now Z spec). I've never had any problems with mine, but RSM doesn't have the greatest reputation.

If you want a light weight underdrive pulley try fast forward performance. http://www.fastfwdperformance.com/ It looks like they are shutting down though so I don't know if you'll still be able to get one from them.