Harmonic Balancer Coming Loose

[taro]

Hello all, I've recently had trouble with my crankshaft pulley coming loose on my '98 with about 170k miles on it. Tonight, I've read about the pulleys wearing out. Question: if my pulley was wearing out, would it cause my crankshaft pulley bolt to come loose or is this a bolt issue (I'm imagining that a pulley that is out of balance could cause the bolt to loosen, but I just want to make sure)?

 

Also, I tightened the bolt to 150 lb-ft was this not tight enough? my torque wrench only goes to 150 lb-ft. should i try to go tighter?

 

Thanks, Taro

[Simon]

150 should be plenty. I'm not sure of correct torque spec on the bolt, but I'm sure that's over. Try a bit of locktight on the bolt. The bolt shouldn't come loose, and I've never really heard of it happening on a Pathfinder. If your HB is coming apart, there'll be looseness between the outer pulley, and the inner hub, as the rubber wears away.

[taro]

Simon, thanks for the response. when i had it off last, i didn't even think about inspecting the pulley itself. i've never even thought about one of them coming apart. i did notice the lip of the pulley being chipped away in some areas, but did not notice any play between the inner and outer sections. it'll be easy enough to get it off, it's barely on right now.

 

the torque spec on the bolt is 141 - 156 ft-lbs (ft-lbs/lb-ft, which is it?). if the pulley's in good shape, i guess i'll put some loctite on it and maybe yank on it a bit more after my torque wrench tells me i've hit 150. Thanks, Taro

[Simon]

well, if there's chipping on the pulley, is it on the insde or outside lip? If it's the inside, maybe it's hitting the timing cover?

[madhornet]

yeah my buddy had his 98 come loose we re torqued it and it was fine for months locktite is a good idea

[colinnwn]

(ft-lbs/lb-ft, which is it?).

 

An engineer would tell your it is lb/ft (pound feet) as it refers to torque (a vector). The alternate ft/lb (foot pounds) refers to a unit of work (a scalar). In practice they are frequently used interchangeably.

Edited September 15, 2010 by colinnwn

[taro]

Well this time, it stayed tight, but the pulley was still moving as if not balanced. I went to autozone and got a new pulley. put it on in the parking lot and the same thing happened. what i did notice was that there was not any woodruff key for the pulley, which i think is the problem, which probably means that i didn't need a new pulley

 

btw-the description for the pulley said woodruff key included when needed, but no key.

 

a quick search did not reveal any sources for keys. would the dealer stock this? were the same keys used for all of the 3.3 or other engines?

 

Simon, the old pulley does not appear to be coming apart. the part that is chipped is on the inner side? i know my pathfinder did sustain front end damage, which did not show up on car fax but i don't know if that had anything to do with the chipped pulley.

 

madhornet, i forgot about the loctite again, but i have to take it all apart again anyway i'll loctite it for sure next time.

 

colinnwn, thanks for the info!

[MY1PATH]

is the keyway on the crank worn? the Key should fit in snug.

 

A slight wobble at low rpm is normal for these engines, some say its consequece of having such a long snout. the Banacer increases effectiveness under speed.

rev the engine lightly, you should see it smooth out fairly quickly and then resume its little jig once it slows down. Id you really wanna see it dance turn your idle down to 300rpm (yes mine ran that low) [warning there is not sufficient oil preassue under 500rpm]

[taro]

MY1PATH, thanks for the info. The bad news is that the slot for the key is damaged and I could not get it seated it its slot, which is a complete bummer. This wad compounded by the fact that my battery is totally dead I presume because the crank pulley is not turning with the crank and therefore the batt isn't charging.

[taro]

My pic didn't come through from my phone. Here's the second attempt.

[taro]

I forgot to add that that plate (the timing belt cover?) behind where the pulley sits (I assume) is only being held in place at the lower section of the plate by the pulley itself as the lower bolt tab has broken off and the lip that contacts the pulley is falling apart. Fun, fun, fun

[MY1PATH]

You'll want to check you timing gear keyway as well it that one goes so will your engine.

I fixed both keyways up with a bigger better fitting key because stock one is too short an if it doesn't stay seated it tears up the hole.

here's what I did

If you ding up the plate in back just pry that off as well. gently tap it flat again, clean up the ding and open the hole up just barely with a dremel.

Idnno why they made it so it snaps onto a groove in the crank when the pulley pushes it against the sholder protruding from the seal anyway.

Inspect your keyways, the original woodruff key was 2-3mm too short which allowed it to walk into the pulley and out of the crank slot. If you are victum of this and they are worn here is your fix.

 

clean them up and have someone with welder come over.

just put a stich weld in the center of the worn area

get a 18x5mm woodruff key (stock was too small)

using a 1/2"x1/8" grindstone on a dremel clean up the keyway and lengthen it to fit the longer key.

It should fit snug maybe even have to gently tap in w/ hammer. Try not grind deeper just yet.

slide the gear or pulley over the shaft without the key to make sure the saft is cleaned up enough

insert the key and check deepth. make the keyway just deep enough so that the pulley or gear has to be slapped in firmly with the butt of your palm.

 

[taro]

MY1PATH, thanks for the info. I have not gotten into welding and so i limped it over to my mechanic who said he has done a couple of keyways with good results. He ballparked the repair around $500, which i guess beats the price of replacing the crank or engine. I'll keep y'all posted.

[MY1PATH]

MY1PATH, thanks for the info. I have not gotten into welding and so i limped it over to my mechanic who said he has done a couple of keyways with good results. He ballparked the repair around $500, which i guess beats the price of replacing the crank or engine. I'll keep y'all posted.

 

 

I paid a guy for is driveway, tools and to stitch the 2 keyways while I spent 2 days doing cams lifter and t-belt.

The only thing I didn't do was the weld itself. the whole deal cost me $300.(not allowed to work on my rented property)

 

If you called one of those portable welder guys he'd have you stitched and you could clean it up for a fraction of the cost you were quoted.

[taro]

MY1PATH, you bring up a good point. my issue right now is time. i am living the redneck life of sorts in that i have the '98 pf, an '82 fj40, and an '04 kawasaki ninja 500. on thursday night i lost two driveshaft bolts on the fj40 and had to park it at an oreillys until yesterday because i wasted too much time trying to source the bolts locally.

 

on the pf, i think i spent thursday evening putting the harmonic balancer back together, realizing it was wrong, i spent friday redoing it with a new harmonic balancer only to realize that the key was not included only to redoit again on saturday once i bought another key only to figure out that the keyway was damaged to the degree that the key would not fit.

 

so on tuesday, i rode my bike to the pf, which has been sitting at the shop, to get the tools i needed for the lc. rode over to the lc. got it fixed, rode back home, then jogged 4.6 miles to get the lc. so now i've got one working car and a working motorcycle. i too currently do not have any space to work on things (apartment complex) and currently do not have the will to do anything more on the pf for now

[MY1PATH]

I hear ya, just tryn' to save u buck but things don't always work as planned. best wishes to ya.

[taro]

MY1PATH, oh it's most appreciated. last year, when i had garage space and back-up rides, i definitely would have taken it on. hopefully, i'll get to the place where i can do multiday projects again. thanks for all of your help. best wishes to you too.

[taro]

my mechanic called on friday. he fixed the keyway and the final charge was $385. if it holds, i'll feel pretty good about the cost of the fix vs the cost of a new crank, etc.

 

he was pretty excited about telling me how he stacked pennies together to approximate the keyway and how the welding he did did not stick to the pennies due to their copper content. sounded great to me!

[MY1PATH]

thats allot better than $500.

did he check the timing gear keyway too?

I use aluminum sheets as backing to hold fillers in place to weled steel and vise versa.

[taro]

Correction: $366.77

 

i don't think so as he didn't mention it and i forgot to ask him about it when i took it to him (he's not a nissan specialist). i'm assuming i had problems with my crankshaft keyway because when my pulley came loose, i let it run when i was trying to figure out what was going on. it wasn't very long, but i'm sure with as loose as it was (at least half-inch play in the pulley) and the alternator, a/c compressor, and p/s pump protesting, it was enough to do what it did. i'll hope for the best for the timing gear keyway for now