Crank Pully Wobble... With video
 

Hey guys... Here is a link to a video of my crank pulley. [ame="http://www.youtube.com/watch?v=fVOSt3_Xwn0"]FT86 Crank Pulley Wobble - YouTube[/ame] What is confusing me, is that the actual pulley looks like it has zero wobble to it... however the bolt that the pulley rotates with has some serious wobble... almost as if it is off center which makes no sense because of how the bolt can only fit completely centered on the pulley... (confusing I know) is this normal? What are your thoughts. As always, thank you for any help you can give.

The way bolts are rolled the head/flange isn't always perfectly center with the shank of the bolt so it's completely possible the head if offset. You can use a dial indicator and turn the motor over by hand to double check the pulley is straight.

It doesn't look like wobble as much as it looks like there is a slight gap between the ID of the pulley and OD of the bolt. Like when someone has some mud just on part of their tire and it looks like it's really out of balance but actually isn't.

Shit! something looks weird...........Attachment 51597

I would guess that as you torqued it, the head pulled a little to one side.
How long is the bolt? Does it have a little slop in the shank? Is there a washer?

Maybe a dab of grease under the head before you thread it on would help it stay centered?

Stop running the car. Get a new bolt.

There's no wobble in the pulley, it's running true. But that bolts certainly isn't. I would also be VERY careful taking that bolt out.

How did you torque it down? Step by step, exactly what did you do?

I paid a shop to do it... I'm just going to go rent tools at autozone and go do this myself. Now I just gotta figure out this part number...

Shiit. Why not take it back to the shop? They should be fixing/responsible

Funny that the manual says:

"Apply engine oil to the thread and washer of crankshaft pulley set bolt."

Part is: Crnkshft pulley bolt 2.0 LITER

http://estore.subarupartswarehouse.c...icleid=1504929

Only $6

meh, mines been doing that since I installed the crank pulley 20,000 miles ago. its just an illusion. youre good.

if the bolt IS actually off, you'd notice it within a 1/4 mile of driving. you engine wouldn't run proper AT ALL.

Man, it's $6 as listed above, and takes about 10 minutes. Why would you risk that?

You'll need an 8mm socket or nut driver (I prefer a nut driver) for two hose clamps. A pair of pliers or strong finger for another hose clamp on a vacuum line. A 10mm socket or nut driver for, three or four small bolts. Pull the sound tube off the diaphram, the inlet hose off the throttle body, and the PCV line off the inlet hose. Take the bolts out holding the filter housing, be careful one hides down a little farther on your right hand side. Being careful of the MAF wires, flip the filter housing up on top of the engine. Use a 14mm wrench to loosen the belt tensioner and pull the belt off of a pulley. Put car in 6th, take out crank bolt. Install new bolt, lube the head of the bolt and thread, torque to 90 ftlbs.

I've seen a few different torque specs, but all are around 90. Some were down to 83 and some up to 94 IIRC. The manual states 14 ftlbs and then 90*. I'm not a fan of torque to yield for this application, but to each their own.

I know this would probably be the right thing to do... IDK why but I don't really trust these guys with my car anymore lol

Thanks for the link!

I wish I could convince myself that this was just an illusion... but I cant lol. I cant "feel the wobble", but it only makes sense that it shouldn't be doing this.

just to wrap this thread up. I replaced the crank pulley bolt... during this process I discovered that the bolt had been installed at about 115lbs... after replacing the bolt and going for 90lbs on the torque wrench there is now very very very little wobble... scary part is that the car actually feels smoother too. Thanks again for the help guys.

This is why DIY is important. Not only do you teach yourself something, you do it RIGHT. I did this pulley install not knowing anything about what to do. Grabbed a breaker bar from harbor freight for a few bucks, gave it a few hard tugs, the rest was history after that.

Never installed coilovers in my life nor knew much about suspension and I did it in my apartment parking lot on jackstands. Sure I bitched when torquing the top hats onto the coils, but at this point in time now, I'm very happy. I saved a lot of money, I learned more about my suspension than I ever knew, and it gives me more confidence going forward doing other projects.

If you have a 1/2" electric (or battery) drill, chuck the bolt into the drill and spin it to see if the head is off. Being over-torqued it is an outside possibility that it started to twist to failure point.......

Glad you found out how to solve this issue!

mine is the same way .. baught a new bolt from subaru and still like that

tq at 90 with a digital wrench tested at toyota ... mine might me a lil less then this video been a few weeks sence i looked at it

Wasn't there something about a pin or something that you had to watch out for when doing this mod? I Swear I saw it in in a video on here (maybe the vortech install & review by dezoris?)

I talked to Jeff at Perrin about this very thing as my bolt head wobbles too. Not quite as much as the first post but it's noticeable. Jeff said that it's normal as the bolts are made up to the same precision, thus may not be perfect. He said it won't affect the pulley at all and I'm fine.

Had the same problem and called Perrin to verify. I did the install like 7 times all with the same result. I'm convinced that the head is just not a proper circle. After driving hard for a few blocks, the wobble definitely diminished a LOT.

The crank nose spacer is what can potentially fall out. It's really not hard to put back in. Did it to me on like the 3rd attempt and I just put it back in, no special mirrors or anything.

Guys, if the bolt is wobbling then it's throwing off the balance of the crankshaft. There shouldn't be any discernible wobble in that bolt or the pulley. Maybe if you used a dial indicator, but certainly not to the naked eye.

Sorry to bring this back from the abyss, but after installing my Perrin pulley, I experienced wobble very similar to this, where it's difficult to discern if it's the pulley or the bolt head. The tensioner pulley itself also has a very slight wiggle, but I'm not sure if that's from the pulley, or engine vibration, or within normal operating parameters (can anyone take a video of their OEM pulley area?)

My story goes that I purchased a new bolt with the intent of replacing it and being good to go, only to find that I had pinched the o-ring and it disintegrated over the course of the 25 miles I had driven the car before the special order bolt arrived.

Now I've replaced the bolt and the o-ring, having lubed the threads and underside of the bolt-head, after torquing to 94 foot-pounds according to Perrin's instructions, and it looks just as wobbly as it did originally.

I'm convinced that the tolerances of the pulley, the machined piece that it mounts to, and the crank itself, are very tight. Coupled with a relatively tight tensioner and a high-quality serpentine belt, it's possible for this to be installed imperfectly and still survive for thousands of miles if need be – but I'm not convinced that my pulley is completely straight yet.

I may disassemble it again, put the OEM pulley back on, and test the straightness of the pulley with a micrometer to confirm. It's plausible these just aren't perfect pieces, or something in the anodizing and curing process thickens it enough to cause an imbalance. If I go this route, I'll follow up here

After a trip from Milwaukee to Minneapolis, the pulley and bolt both seem mostly fine. I think some of the perceived wobble may just be natural engine vibration, since the pulley area appears to not have any engine mounting point near-by.

On higher-than-idle revs, the pulley and engine both look straight and stable. On warm idle, the engine does have a tendency to wiggle around a bit. My verdict based on my anecdotal experience still stands; a properly installed pulley, with a new bolt and o-ring may appear to have some wobble, but the tolerances are so tight that the only way to cause damage is to be irresponsible. If you're worried about it, check it every day or two.

I also recall reading in this topic or another similar one, worries about poor gas mileage immediately after installation. I also had this happen; for the first 100 miles or so I was down to a 28.5ish average, when I'm used to getting 34 on 91 ethanol-free octanes. Now that the brain learned about the new bits, everything seems back to status-quo.

MPG bit might be due you removing power when installing, thus ECU reset & relearning fuel trims on startup after assembling. Can be shortened (search in forum).

Computer learning has to be what caused my low MPG. It was a dramatic decrease that then dramatically improved with no difference in my approach towards driving the car.

Yeah, probably. This bit (and how to quicken ECU reset dead pedal fix) IIRC mostly came from tuning/reflashing ECUs side, but might be useful in similar cases, is even mentioned here after pulley installation.

Did ur car shut off due to wobble?

Are you talking to some voice in your head out loud here or the guy from 6 years ago that had this problem?
Just in case he doesn't report back, and he wont since you didn't quote him to ask the question and he last posted some time in 2014....
If your car shut off, it isn't from a wobbly looking crank pulley bolt.
Here is an instructive Youtube video that might help you for the car shutting off issue: [ame]https://www.youtube.com/watch?v=AynXoLjYrKc[/ame]

Also, for your benefit if it turns out to be the gas issue your having, don't keep kushin. :lol:

my bad not really used to this site yet but anyways car shut of while on the freeway like i lost all engine power my lights where working but when i was pulled over i couldn't get it to crank over and then i got it towed home thought it was a starter issue got a new starter got it to crank over it claks anytime over 1800 rpms but once i depress throttle it dies out. i had it running for an hour the other day almost and that was without giving it gas sounded normal i data logged what i had but no clakking sound during that idle period also when car lost power i got p0345 p0340 and p0198 p0197 dtcs got new cam sensors check crank sensor altenator my grounds are good nothing looks to be open on the harness that is visable. thought it could be highly excessive engine knock due to a quater of the tank being 2 and a half 3 week old ethanol but not sure it could be due to anything from loose flex plate but i can crank seems a lil hard to turn with the tools i have and the time i also have available due to my job but gonna prob have it towed to a shop im still under warranty.

That's beyond my pay grade. For sure make a separate new post of all that in the Issues | Warranty | Recalls / TSB here: http://www.ft86club.com/forums/forumdisplay.php?f=72 and I'm sure great help will be along shortly.
If it's under warranty you should be good to go but if I read that correctly, you're running E85 which means they will deny everything possible since you are running that and a tune to go with it. If that's the case, maybe try
filling with some 93 and put back a regular gas tune in and see what happens before surrendering it to the dealer. There's a couple real good people in the "software tuning" subforum in here too that could help if it's all
stemming from the tune.

alright cool thanks man i appreciate the help yes it's still under warranty. plan was to flash back to stock and empty tank and let the motor idle for a lil while so trims will be normal. hopefully they wont trip on the catback ill put oem headers back on also

Catback should't be an issue with any dealer. The header is 50/50. My dealer didn't care though and even with the tune still on it still in there they did warranty work on the fuel pump.
You don't want to switch it all back to OEM and bring it in to have nothing wrong though, be sure it's nothing you've done. Get the E85 out and regular in and try a gas tune. Then I'd
try removing the aftermarket header and back to stock tune. And then after all that, if there's still an issue, bring it in. Remember the dealer can tell if a car has been flashed and if it you
bring it back right after the stock flash going in they may give you trouble. If you removed everything you did in steps and check for codes each time and still are having the issue at least
it's arguable that it wasn't anything you did that is causing it if they confronting you about the tune.

And again ask in the tuning section and/or maintenance since they might save you a trip to the dealer altogether without removing anything or emptying the tank.