Wobbly Harmonic Balancer (main pulley) on 1HDFT

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1996 1HDFT motor in a 1996 80-series. I'm on a road trip mtn biking Moab UT, Fruita CO, Hurricane UT. Currently in Fruita; Front main seal suddenly started puking oil. I had it off 5000 miles ago to weld up a cracked timing case. It's still tight (just checked the 32 mm bolt).

Here's the weird thing: the main pulley wobbles when the engine is running. It makes the belt jump up and down a little. Could my harmonic balancer be coming apart?!
 
Better get on it soon before it seriously damages your engine. I've just changed mine after reading all the horror stories online.
 
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I remember when I noticed my harmonic balancer wobble I asked a mechanic if it was ok, and he assured me it was fine. After about 5000 km of driving, sometimes up to 90 mph on highways, I googled up the issue and the search results varied from nothing damaged yet, to crankshaft key way damage, crankshaft nose run out, and catastrophic engine failure. Luckily I came out unscathed. Fortunately all the damage was done to the balancer and the key. I think that as long as the 32mm bolt is tight and your oil level is full, you should be fine the rest of the way. But i'm definately no expert, this is just my experience and take on the matter. I'd change it out as soon as you get the chance, to prevent any damage to the crankshaft.
 
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Your welcome! Be sure to install a new o-ring that sits in the indent of the inner wall of the harmonic balancer that seals between the crank and balancer. I nearly forgot that.
 
More than likely you did not re-check the crank bolt torque a couple hundred miles after having it off? Sure it's torqued? Anyways bolt starts loosening, keyway gets damaged and then wobbling - hence leaking oil. Only gets worse until, like me, you loose your front seal completely (right at the trailhead to Los Naranjas Road - bummer)

Would recommend re-torqueing ASAP - at least until you can fix it properly. May need new Balancer if rubber separated, o-ring and seal.

Luckily Jan and W.C.C. was able to ship us down a package. Edit: luckily you have one!

If you keep driving her you risk damaging the keyway seat, and you will be welding the crank at a minimum....

Know the feeling - good luck!
 
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I replaced mine when the shop I go to had a customer have his truck towed in, when the Harmonic Balancer sh!# the bed. Mine had fine cracks in it and might of had more life in it, but after seeing all the damage the truck had, I rather be safe than sorry.
 
Made it to a friend's in Flagstaff AZ where I can work on the rig.
Georg from Valley Hybrids is sending me a spare balancer and seal. (Ordered a new one from Japan4x4). Had to buy an electric impact (figure it's still cheaper than paying a shop), puller, and bucket to catch coolant. Now if only the weather would cooperate; expecting snow this weekend.
 
Well... Looks like the crank is pooched.
Gonna be a long walk home.


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Oh man, that sucks so bad. Not how I was hoping this would go.
 
Well since I can't make it any worse, and I'm 1000 miles from home... Let's see what we can do. I have a clean used balancer, new keyway, new oil seal, and a tube of JB-Steel. First round only filled part of the hole. Second round is getting close. Need to wait another hour before polishing.

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gerg said:
Since you can't make it worse....weld that bastard in there!
Click to expand...

How bad would the imbalance caused by the weld be for the rest of the motor? Or would new bearings completely resolve any issues it could cause?
 
I was thinking fill the chipped defect with weld and carefully buff it flush for the new pulley. I doubt it would cause an imbalance at all and if it did it would be central. Heck, if it were me I'd be tempted to lay down a couple opposing beads on that bastard pulley too. New crank means pulling the engine and almost taking the entire thing apart. Yould have to be pretty serous about keeping crap out of your oil pan, but youldbe changing the oil anyhow. If you do anything, don't run it with the jb weld. I love that stuff better than binder twine, but it won't hold long at all.

Edit. After an exhaustive 10 minutes of reading, apparently its Superbad to weld on your crankshaft. Oops.
 
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Ok so since reading many fixes on subaru engines that suffer this I came across a good possibility for you. Fortunately loctite, I love that stuff more than franks hot sauce, sort of created a system to fix this issue in a temporary/ semi long term way. Enough to get you home. Here is a couple links.

http://www.miata.net/garage/hsue/crank/loctite_3.htm

http://www.miata.net/garage/hsue/LoctiteCrank2.html



So my very quick nursing advice of welding is not advisable as it weakens the crank nose and well... It can sort of break off some peope said. Welders actually. Who weld stuff for a living. I'm a nurse and don't weld, but rather melt steel together sometimes.

Looks very doable.
 
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Sorry about that man. On the bright side it could of been much worse. At least it seems to be repairable in the short term at least . Maybe a creative machine shop can can come up with a long term fix on the cheap. Another product that seems to come on top of the list is belzona (1111). It's used in Industrial applications. On ebay there's one 1kg for sale a bit less than $200. Maybe something worth discussing with your machine shop.
 
It would be pretty fancy welding as the entire 360 degree of the crank is scored. It's back together and holding. I'm pretty sure that most of the force is not normally on the keyway, but rather the press fit (which was really tight using the full power of a Ingershold Rand electric impact... Rated to 750lbs to drive the pulley on). So hopefully the small dab of JB-weld will hold for 1000 miles. I've got a line on a used crank... Or a new one for $900.
The head on this motor is brand new; only drove it to the end of Baja, then Moab/Fruita/Sedona so it might have 6000 miles on it. I think it's worth a new crank...

Leaving in 5 minutes for home. Fingers (Birfields) crossed.
 
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