TPITuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
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Just noticed Crank Pulley Wobble on LB9 - What to dO?
My crank pulley is wobbling pretty bad and the car is idling rough and shaking... how bad is this... what effects can it have on my (118k miles) 5.0 LB9 TPI... auto... ?
By crank pulley, I assume you are talking about the harmonic balancer. It is made of 1 metal hub with a metel ring around it with a thin rubber devider. This is what absorbs the vibrations created by the engine. In time the rubber can wear and the unit does not perform well. You can replace for $30-$40. Need to do before the whole thing comes apart. Most times when that happens the inner hub breaks off and drops into the oil pan taking the timing chain with it.
__________________ 1972 Corvette
Original LT1 350/HO Engine
Keith Black 9.7:1 Pistons
Replaced original Solid Lifter Cam with
Comp Cams Marine Roller Cam
Original 4 Bolt Steel Crank
336 Posi Rear Chunk
1991 Speed Density TPI setup
With Holley Stealth Ram Intake
DFI 7 conversion in progress
You need to determine first what is actually bent. Wether its the crankshaft snout, the pulley or there's something wrong with the Balancer. Remember the job of the balancer is to smooth out the rotation of the Crankshaft. If this falls to happen, it can snap the crank in half. If it's the pulley, your going to have problems with the belts, sooner or later. If its the snout, I'd go ahead and replace the crank and rebuild the bottom end while your there. In the long run you would be time and money ahead. (IMO)
Damn, I hope its not the snout... and rebuild? I doubt I would I need the car on the road ASAP, plus I don't know crap about how to rebuild, it would probably end up running worse!
So I guess to determine this I would have to remove the pulley and just get a close up inspection of it?
Replacing the balancer is fairly simple. Take the belts off.Remove the center crank bolt and then the smaller bolts holding the pulley on. You'll need a Harmonic Balancer puller, its shaped something like a "Y". Some people like to put the crank bolt back in minus the washer at this point. You'll use a bolt at each leg of the "Y" and bolt the puller onto the balancer. Then there is a big screw that screws into the center of the "Y" This center screw will then be tighten down against the crank bolt or whatever your puller uses, and by turning the screw it will draw the balancer off.
Important Notes: Some like to use a anti-seaze compound between the snout and the inside of the balancer. My Fluidampner came with it. And remeber to PROTECT the crankshaft threats, this is probibly the most inportant part.
Speaking of Fluidampner I got a kit from Summit several years back which included everthing: Dampner, Timing Mark and a very high quality puller/installer. Complete with instructions. Just an idea.
Snouts usually don't bend unless you've been jacking up the car by it or have the belts way too tight. And Pulleys just don't bend either, for that matter. My guess would be the balancer. But make certain first.
Try snugging down the 3 pulley bolts and the center balancer bolt. If that doesn't fix it, remove the assembly and replace it. It may or may not be a case of the outer ring slipping. However, keep in mind, if the pulley is wobbling, then one of 2 things is bad. Either it's not bolted down right or the entire balancer assembly is loose/broke. The pulley is mounted to the inner hub, the same part that bolts to the crank.
Hey thanks for all the info elcamin0_77us, it'll help me out a lot. Stekman I'll see if its just not bolted up right or something like that, it sounds like a much easier fix . I'm going to try to compile all the parts needed from AutoZone, since I can get a discount from there.
I don't know how this started I just got the car, hopefully the previous guy (who did seem desperate to sell it) didn't mess up the snout.
No I can probably email to ask him, there were lotta things wrong with the car that I didn't even think to check, pretty stupid of me... like the cd player not working, he mentioned it was new, so I assumed it would work and didn't care to check it, boy was I wrong. I also assumed the passenger side door was lockable/unlockable via the actual key, but I didn't notice that either, I should have checked when he already had it open for me! He pretended to be honest with me and told me all the things that were wrong, except for the major ones!
These are my choices... anyone know whats so high performance bout that pioneer high performance? I think I'll go for Dorman if the problem is in fact the balancer.
Originally posted by C4 Suke No I can probably email to ask him, there were lotta things wrong with the car that I didn't even think to check, pretty stupid of me... like the cd player not working, he mentioned it was new, so I assumed it would work and didn't care to check it, boy was I wrong. I also assumed the passenger side door was lockable/unlockable via the actual key, but I didn't notice that either, I should have checked when he already had it open for me! He pretended to be honest with me and told me all the things that were wrong, except for the major ones!
Sounds like the guy I bought my first car from. Sold me a '90 Plymouth Sundance w/ 147k miles on it. I put 9K on it before I totalled it. Needed a LOT of work, and I wish I had replaced the transmission mount. That was stupid of me not to do...ended up messing the tranny up a bit, but I never had to worry about it since I totalled it anyways. Massive brake failure followed by locking up the steering wheel. Now though, the guy and I are pretty good friends (we're co-workers at an apartment complex). Oh yeah, on that car, my passenger side wouldn't work with the key at all either
. I'm going to try to compile all the parts needed from AutoZone, since I can get a discount from there.
