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Crankshaft Pulley Moving

13K views 23 replies 8 participants last post by  zjosh93 
#1 ·
It's moving in & out.

After my bout of changing the radiator hose on Fri. and putting on a new serpentine belt, I put in new coolant and let the engine run for a while, then parked it out front. (The hose blew out & the belt went out at the same time.)

Today, started the Jeep, got almost to the corner (1/2 block) when I heard a noise, then lost my power steering. Seems I threw the new belt.

I finally got the belt back on and tightened the adjusting bolt and the other 3 bolts to the pump. Did not put the shroud back on, so I could see what's going on.

This time I started the the engine so I could watch the bottom of the fan blade near the crank pulley. I gave the engine a little rev.

Holy crap! The crank pulley moved in & out then out as I give it gas, then let off.
The pulley itself does not seem loose (like the bolt backing out), but the between fan & pulley keeps me from getting my hand down there.

If it moves in far enough, the edge of the belt hits something, and that is what threw the belt off, like what happened when I gave it gas from the stop sign. Engine has 330K miles, but runs just fine.

It's a problem I've never run into. Anybody know why this is happening?
 
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#3 ·
I was worried about something major being bad. I will check the pulley itself, but have a bad disk in the back so it's a bit uncomfortable for me.

Problem is that this '94 ZJ isn't worth putting any serious money into, and the used market near me is a bit short on a good affordable used GC.
 
#5 ·
It's not a pulley but a harmonic balancer, pozner, sometimes called a damper, attached to the front of the crank with the belt grooves in it.

There's a rubber isolator which prevents vibration and help holds it together. Chances are your rubber has come apart/broken down letting the non-bolted part of the balancer to come out further than it's supposed to. I would not drive it like this until it's fixed.

You'd probably get by in replacing the balancer and would have to have a balancer puller. Many parts stores have loaner ones and see if you can find a compact one so you don't have to pull the rad. May have to anyhow if not enough space.

Here's a couple balancers from Rockauto and the Dorman is $30 plus shipping while the Dayco is $37 w/probably $10 shipping.

http://www.rockauto.com/en/moreinfo.php?pk=14154&cc=1310943&jsn=426&jsn=426

http://www.rockauto.com/en/moreinfo.php?pk=5431326&cc=1310943&jsn=427&jsn=427

Note the mention of "rubber" in both these descriptions, and it failing it what probably happened to yours. Bet you could pry the front part of the balancer out a little while the bolted part of the balancer would stay where it is. This is not normal.

Hopefully that's all the problem is and don't believe it's a major/pricey disaster. Good luck.

PS. many would replace the front crank seal while you have the balancer off and probably only $5.

PSS. I can relate to a bad back disk and had 2 back surgeries 10 years for a herniated lower disk. No fun and still have some sciatic pain/problems.
 
#6 ·
It's not a pulley but a harmonic balancer, pozner, sometimes called a damper, attached to the front of the crank with the belt grooves in it.

There's a rubber isolator which prevents vibration and help holds it together. Chances are your rubber has come apart/broken down letting the non-bolted part of the balancer to come out further than it's supposed to. I would not drive it like this until it's fixed.

You'd probably get by in replacing the balancer and would have to have a balancer puller. Many parts stores have loaner ones and see if you can find a compact one so you don't have to pull the rad. May have to anyhow if not enough space.

................

PS. many would replace the front crank seal while you have the balancer off and probably only $5.

PSS. I can relate to a bad back disk and had 2 back surgeries 10 years for a herniated lower disk. No fun and still have some sciatic pain/problems.
You are, of course, correct. I can't actually drive it on the road now. I did move it slowly into the yard and took it apart again.
It started with this.



This is what I found after reading your post.
Removed the fan & belt.



Yes, the harmonic balancer is loose.


And here it is.




A mechanic I use for the harder stuff installed a trans cooler. Getting the radiator is going to be tricky, this time. I only have hand tools and I am unsure if I will be able to get that crank bolt loose, working in my front yard.

Thanks for the links to the new harmonic balancers. Going with the Dorman. Not sure on a time-line. New seal is a good idea. I have bad luck replacing seals. If I can't get the bolt loose, I'll have to call a wrecker to deliver it to the garage. Hate to do it, but I may have no choice.
 
#7 ·
Yep, that isn't the first time I've seen a photo of the outside of the harmonic balancer sitting on top of the rad.

You best start hosing down the crank bolt/front of the balancer with rust cutter now. And if you're going to replace the front crank seal you could put some heat around the bolt even if it's using a small hand-held propane torch.

And speaking of leaking crank seals mine's leaking on my 04 4.7 WJ. I just purchased this compact harmonic balancer puller to try and avoid pulling the rad. Still have to remove the hydro fan first. Yuk and may have to pull the rad anyhow!

https://www.amazon.com/Performance-Tool-W89712-Harmonic-Balancer/dp/B013OH5VN6/ref=sr_1_1?ie=UTF8&qid=1485221663&sr=8-1&keywords=compact+harmonic+balancer+puller

Since I can't see the front of your harmonic balancer I don't even know if this one would work on yours? And since it isn't very HQ I best try to use it within 30-days in case it falls apart! Lol. Good luck.

PS. nice photos and helps to point out the problem!
 
#9 ·
Thanks coralman and the price was right at $39! ;)

I just opened the harmonic balancer puller kit 2 days ago and it doesn't look too bad quality-wise. It's still going to be a real tight fit and it's been years since I've pulled a HB.

In looking at the main screw shaft it looks like one of the spacer rods only goes up in the inside about 3/4"-1". If I have to get the puller closer to the damper to avoid the rad I almost thought about cutting one of the spacer rods to a shorter length. I realize this may be too short to get the whole damper off and could then switch to a longer rod if needed.

Curious what's the best way to stop the crank from turning when trying to loosen that large damper bolt? I saw some say they remove the starter and jam a big screwdriver against the flex plate ring-gear teeth then against the trans housing. Does this sound logical or is there a better way? Thanks!
 
#10 ·
Both balancers I've replaced were already aftermarket so they had threaded holes for the puller. That might make for a smaller package, but I never had to pull my radiator. The threaded holes also are a good place to put a bolt so you have something to pry against to hold the crank while loosening or tightening the bolt. I'd guess you might be able to fangle something for the non-threaded versions. I've used a block of 2x4 in the starter hole on many cars. To loosen the bolt you can also put a breaker bar on the bolt, turn it to wedge it against the frame, and use the starter to break the bolt free. Just be careful, a breaker bar thrown by the starter is a dangerous thing. Doesn't help tighten it though.

IMS you need to put some RTV under the washer to seal the key way.

Don't forget you'll probably need a crank pulley install tool as well. The balancer probably won't slide on the crank far enough by hand and you shouldn't hammer on the crank.
 
#11 ·
Thanks for the good info Josh! Jamming a chunk of wood in the starter hole sounds like a better option than using a screwdriver/metal.

Afraid I might have to go to the parts store for a loaner balancer installer since most the ones I've seen are pricey kits. I thought maybe I could pull the balancer on with the bolt/washer but have read you risk stripping the threads. And like you said you don't want to pound on the front of the crank with a hammer.

I don't think I'll have a problem getting the crank seal out of the timing chain cover but what about install? I though maybe I could just tap it in with a hammer but don't think it's supported very well from behind and don't want to crack the cover which may be aluminum. Do you use a seal installer for installing this seal and if so what type?

I had watched the below video before of the guy cranking the engine to break the crank bolt free but seemed like a pretty nutty guy to me. Main thing I didn't like was he had the breaker bar handle against another pulley (AC in this case). In bracing the breaker bar against the frame or elsewhere sound like a better idea.



Thanks for any info!
 
#18 · (Edited)
Thanks for the good info Josh! Jamming a chunk of wood in the starter hole sounds like a better option than using a screwdriver/metal.

................

I don't think I'll have a problem getting the crank seal out of the timing chain cover but what about install? I though maybe I could just tap it in with a hammer but don't think it's supported very well from behind and don't want to crack the cover which may be aluminum. Do you use a seal installer for installing this seal and if so what type?

.....................................

Thanks for any info!
Removing the starter and jamming the starter ring is one of the normal techniques. Another is putting two 5/16 X 3" or 4" bolts into the HB hub, use a bar in between to keep the crank from turning.

Back when I worked the parts counter at a big repair shop, the mechanics removed the radiator, stuck an impact gun & socket on the crank bolt, and after a couple of hits, the bolt came right out.

The mechanic said he almost used the starter hole technique because it's easy to remove those 2 bolts to drop the starter, but found another way (he didn't share). This was because he decided not to pull the radiator. He said it was a real job at first, but he has a shop to work in, not the grass.

The puller he used was one of those with 3 ears, with bolts through it, into the hub. A center bolt is tightened, pulling the HB hub off. We all know what it is, but it was NOT one with the 'hooks'.

I noticed a photo in a repair manual to install the seal. They used a huge socket to cover the seal's diameter, then gently tapped the seal home.

Good luck to us all.
 
#12 ·
The block of wood is the safest and surest bet I know. It's soft enough that the teeth dig in but strong enough to take a ton of torque. As far as the balancer install tool, I've always rented it. My other cars don't need it.

I have a few seal install tools I made out of PVC. 2" PVC and various PVC adapters will get almost any seal in straight and safe. I tapped the seal in with the cover on the motor the first time and on the bench the second time. It doesn't take a lot of force. I wouldn't worry about cracking. They make a specific tool to set the seal depth and whatnot. I think Coralman has one. But then perfect is the enemy of good enough.

You could probably fake a balancer install tool with some 1/2-20 all thread, a common 1/2-20 lug nut, and a stack of washers. With clever shopping you could probably get it all for under $10.
 
#14 ·
The block of wood is the safest and surest bet I know. It's soft enough that the teeth dig in but strong enough to take a ton of torque. As far as the balancer install tool, I've always rented it. My other cars don't need it.

I have a few seal install tools I made out of PVC. 2" PVC and various PVC adapters will get almost any seal in straight and safe. I tapped the seal in with the cover on the motor the first time and on the bench the second time. It doesn't take a lot of force. I wouldn't worry about cracking. They make a specific tool to set the seal depth and whatnot. I think Coralman has one. But then perfect is the enemy of good enough.

You could probably fake a balancer install tool with some 1/2-20 all thread, a common 1/2-20 lug nut, and a stack of washers. With clever shopping you could probably get it all for under $10.
Thanks again for the info Josh! I wouldn't doubt I could make the seal installer. I have plenty of 2" PVC pipe, adapters, and even removed metal pipe that size for all the plumbing I do here. I've also heard of others using all thread rod with nuts, washers, etc, for pressing it in.

I've replaced plenty of trans and TC case seals and will just be careful around the timing chain cover.

Yep, Mr. Miller Tools has them all! :D

I'd pull the radiator.It makes a lot of stuff a lot easier, particularly when you're trying to fit the puller in there.
I'm going to put a piece of 1/4" plywood on the inside of the rad to protect it. If I find there's not enough room for using the balancer puller I'll definitely be pulling the rad. I know it would probably be easier to pull it ahead of time but would rather not pull it if I don't have too. Thanks for the input.

PS. I cut a lot of firewood and would bet I could cut just the right size piece of log to set on the ground if I wanted to brace the breaker bar handle against if for removing the crank bolt using the starter. Could even attach the handle to the piece of wood so it won't move. May end doing that if I can't break it loose by hand since I'm sure all the road salt has helped seize the bolt.

PSS. haven't heard much from pozner who started this thread and don't want to take it over. Curious if you're going the diy route or take it to a mechanic?
 
#15 ·
While I had to stop reading for a second with the words "perfection" and "enemy" in the same sentence, I have to agree with Josh. It doesn't matter if you have all the tools and do everything you can do to insure a good outcome. Sometimes stuff still turns out like ****. As to the OP, I would consider going back with a mopar balancer if there is anyway you can swing it. A parts dude at oreily's told me they had to stop selling Dorman awhile back because of quality issues. At the time mopar balancers were on BO, so I got one made by a company out of Australia but I can't remember the name. It has lasted since installed in 2014 without issue and has been removed and installed several times. Dorman may have improved quality since then but I don't know how you would tell.
 
#20 ·
Nothing wrong with having it done if circumstances push in that direction. At 67 I have some physical limitations too and I'm not going to risk my back dropping a transmission alone. There is also a big difference between doing some jobs on a lift vs crawling on concrete.

Interestingly it was my long time go-to mechanic who noticed that my balancer was starting to go (wasn't as drastic as yours) and it was he who said I'd probably enjoy doing that job myself. (BTW I used the 'two bolts in the pulley and a long screwdriver' technique to hold the crankshaft)
 
#21 ·
I hope those Dorman Balancers are OK since that's what I used. Mine came off in the driveway when I started it (clang-klank). The wife said "what the hell was that?" I said, that's the sound of you walking to work. Mine landed on the ground. I used a 1/2" breaker bar wedged against the frame and just gave the starter a slight bump. Bolt came right out. Bought a puller set from AutoZone and took it back when I was done with it. Since the radiator was leaking, I took it out which gives you a lot of room to work with. Other than the parts guy at AZ transposing the numbers and giving me the wrong balancer the first time, which set off a series of unfortunate events, not a bad job having to do it out in the street. My back isn't that messed up (yet) but laying under a car and having to work overhead scrambles my inner ear so I can't walk straight for about a week afterward. Wish I had access to a nice car lift, too big to fit on the motorcycle lifts at work.
 
#23 ·
I used the Dorman as well. I think it will work just fine.

For a cherry on top of these travails, I thought I had finally trashed my AC compressor during the summer. It made a horrible sound, like chunks of metal inside. It was worse when I was right up on it, with the hood up and scared me enough that I ran to the door to shut it down quickly.

Guess what? It wasn't the AC compressor, it was the bad harmonic balancer making the awful racket. It never even entered my mind that it was the harmonic balancer. And anyhow, I couldn't see it from the top.

After I got the ZJ back, I got brave and turned on the AC. There was no noise at all and it was still blowing cold air (it was 85 the day I picked it up. Sorry, snowbirds.). I checked it again on Saturday with a very short trip to the store. Works fine, no more noises. The weather turned a lot cooler, so no need to purposely run the compressor, but I'm a happy camper.
 
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