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Major crankshaft issues
Topic Started: Nov 26 2011, 10:38 PM (7,534 Views)
compjake
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So, while trying to diagnose the cause of the loud engine knocking, poor idle, and its refusal to do 4000rpms or over I finally found the cause of most my issues if not all of them. But, I'm guessing its going to be a very costly project now. :scared :x
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Thats what the end of the crankshaft looks like when I took the pulley off. To me, this looks really really bad and I'm guessing its time to replace the whole crankshaft. As much as I love being right, please tell me I'm wrong. :'(

Rebuilding this engine is something that financially I just cannot handle right now, this car has my disabled mothers main source of transportation to get to and from dialysis. (That's why she lives with me)
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obaja
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Diesel Power

machine shops can fill that in with weld and machine it back to the correct size for the key. You will have to remove the crank. Hope somebody has better news
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Johnny Mullet
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Fear the Mullet

I have heard of people setting the sprocket on straight and packing it with JB Weld and it will hold. Another guy drilled holes and bolted the sprocket on to prevent a major repair.
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compjake
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Thanks for the ideas but, If I have to remove the crankshaft its going to be replaced. I cant take any chances with this, when I repair this it has to work and if I'm going this far into the car I may as well just do it the right way the first time.

The way I see it is, If i cant grind it out with my dremel and install a new key it will have to be replaced.
I know welding it may make it good as new but I'm borrowing a car to get my mom to dialysis, so I cant wait for a machine shop to take care of it. If I have to pull the crankshaft then I need to just pull the engine, replace the crankshaft rebuild the engine and get it back on the road. I'm working with very little time before I have to return the car I borrowed then I'll be stuck with nothing.
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Old Man


I think maybe I would try getting or making a woodruff key the right size out of brass, then fill weld the space left over, remove the brass key, (weld won't stick to it), hand file the weld back til the sprocket slips on, then new seal, new woodruff key, and install sprocket.

at least that is what I would do in that situation
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compjake
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Great idea, if I had a welder. lol
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obaja
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Diesel Power

Johnny Mullet
Nov 26 2011, 10:59 PM
Another guy drilled holes and bolted the sprocket on to prevent a major repair.
How?
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Memphis metro


obaja
Nov 26 2011, 11:44 PM
Johnny Mullet
Nov 26 2011, 10:59 PM
Another guy drilled holes and bolted the sprocket on to prevent a major repair.
How?
One way would be to drill a hole thru the gear and tap it and put a set screw in it.

Like this, this is not a metro gear but you get the idea.

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You could tap the lip portion of the gear for small set screws or you could grind out a center portion of one of the teeth on the gear flat, leaving enough gear on both sides for the belt but providing a space to drill and tap for a larger set screw that would mount flush within the gear. A good tight set screw should prevent wobble. After seeing a few threads about this problem, me think I will do this to my current rebuild in progress. Although the problems I suspect are comming from previous work being done and the crank gear bolt not being torqued properly. Never the less, its not any trouble to drill and tap for added precaution.
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compjake
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Sounds to me, my best chances are to buy a welder from harbor freight and try to weld it up as best I can. If worse comes to worst I'll return the welder and use the money for the rebuild. :/ i wish there was a better option.
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Old Man


enginedoctorgeo
Nov 27 2011, 12:04 AM
A good tight set screw should prevent wobble. After seeing a few threads about this problem, me think I will do this to my current rebuild in progress.
Posted Image

After drilling the gear and before tapping, slip it in place and drill a small dimple into the crankshaft. This will be a tremendous help in locking everything into position when you tighten the screw.
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Cobrajet25
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Easy fix.

2.2L Subaru Legacies are NOTORIOUS for this. I bought a MINT '92 Legacy AWD sedan for under $400 with this exact problem. Seriously, one owner, bought locally, every maintenance record since new, original window sticker...the works. One of those cars you find once in a blue moon. The mechanic said the engine needed to be replaced. Ha! Under two hours of wrench time and $16 worth of used parts, and it's back on the road. Hasn't given me a problem since, and that was 7,000 miles ago.

All is not lost. Contrary to popular belief, the keyway isn't designed to take the torsional load of the crank pulley and belt-driven accessories. All the keyway does is keep everything lined up when you are torquing the crank bolt. But the key and keyway are forced to take that torsional load when the crank pulley comes loose and the friction bond between the bolt, crank pulley, timing gear, and crankshaft is reduced or eliminated. After awhile, they fail and then strip out like this.

It looks like the side of the keyway that would hold everything in alignment is still okay...it's the other side that has "wallered out" due to the pulley bolt working loose. When you are tightening the bolt, all the components want to rotate clockwise, and all the metal appears to still be present on that side of the keyway. In fact, that side of the keyway looks perfect. Put simply, the keyway stripped out on the side that DOESN'T MATTER in terms of the key and keyway performing their intended function.

Get another crank pulley and Woodruff key. Slap it back together, making sure to have everything in alignment when you tighten the bolt. Once the pulley and key are on, turn them as far clockwise as they will go. They should be in perfect alignment. Using a bit of NON-PERMANENT Locktite on the bolt is a good idea. Make sure to torque it to specs.

You are good to go. Try it.
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earthtoad


.....Anybody Up White City, Oregon way that could Help Get CompJake's Mom to Dialaysis 'til he gets Back on the Road........
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Memphis metro


I was thinking they had come up with a method of performing dialaysis at home. Has this become a reality? Or is clinical dialaysis still the norm?
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clarkdw


I have repaired a number of pulley problems like this on the job. Install the crank sprocket and locate it using a new woodruf key. If the sprocket is too badly damaged to be snug or locate properly use a replacement. Once you are sure the sprocket will locate correctly drill a 3/16" hole in the sprocket/crankshaft. Try to keep the hole approximately centered so it is half on the sprocket and half on the crank. If you can drill in at least 1/2" it should be sufficient. Now get a 3/16" steel dowel and drive it in the hole you just drilled. Presto! New key. It will be retained in place by the bolt and washer. Hardest part is making sure the sprocket is back in the correct location but it looks like your crank still has one side of the keyway good enough to locate the sprocket.

If you don't have access to dowels you can drill whatever size hole you want, cut off the shank of the drill bit and use that. There is always a way.

Removing the crank and rebuilding the engine or replacing the whole engine for a small thing like that doesn't pay. As long as the crank is not completely trashed and the sprocket flops around it should be ok. When you install the sprocket for the final time you could add devcon or JB weld to the keyway as well for extra security and Loctite the crank bolt.
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Scoobs
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:D

if you want a better crankshaft, i got 2 sitting in my garage. for a 3 cyl. if your interested send me a pm.
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