pully problem

[luckyflip]

well today i was driving home from the mall when i hear a "thump" sound.As soon as that happens the battery light turns on and the ac isnt as cold.At first i thought my belt snapped but it kept driving ok. well i get home and see what had happened,what i find is suprising to me ,the pully where the alt/ac belt goes came off a bit and turned sideways a bit,the powersteering belt is the only thing holding it in place. i always thought it was all one peice. so my question is what exactly do i need to replace? im stumped. and also if i take it to a shop how much should they charge me? meaning what too much .
thanks guys

[PhatAccord]

sounds like your crank pulley broke off...
hopefully you just need a new crank, new drive belts and possibly the little crank key that lines it up (if it fell off)
check to make sure the threads on the crankshaft are okay

[NAiL05]

Agree with the crank pulley issue. I had the same issue. Over time the rubber dampening in the middle of the pulley cracks and the pulley decides to separate. Just change the pulley and you will be fine.

[johnl]

The pulley isn't just a pulley, it's also a harmonic damper made from two pieces of metal (inner part is steel, outer part is typically cast iron, because cast iron is heavier than steel). These metal pieces are bonded together by a flexible rubber insert.

Harmonic crankshaft vibrations cause high frequency shaft oscillations (flexure) and also cause movement between the two metal damper components and within the rubber insert. These vibrations are strong enough to cause the rubber insert to get fairly hot as the rubber absorbs the energy of the vibration, and over time this 'heat cycling' causes the rubber to degrade and eventually to fail (oil is also very bad for the rubber). This is more of a problem for engines that see a lot of higher rpm work.

The point of the damper is to dampen the harmonic vibrations that would otherwise cause the crank to oscillate excessively, potentially strongly enough (at higher rpm) to cause eventual crank failure. You need a new damper / pulley, but if you can't afford a new one then a SH unit will get you out of trouble, but inspect any SH damper very carefully for cracking / seperation of the rubber insert.

It's a good idea to inspect the damper rubber carefully whenever you're working in that area, and a lot more often for an engine that sees a lot of rpm frequently...

[nope]

i'm pretty sure wed3k or d112crzy said that F series are internally balanced..
search confirmed

besides, who uses the word "oscillate" lmao jfk =)

[luckyflip]

Alrighty thanks guys .crank pully it is.
One question the harmonic balancer and the crank pully are two different things?

[NAiL05]

i'm pretty sure wed3k or d112crzy said that F series are internally balanced..
search confirmed

besides, who uses the word "oscillate" lmao jfk =)

Its there to help absorb shock. And an engine cannot be 100% internally balanced over time. Parts wear out.

[johnl]

It's got nothing to do with primary rotational engine balance. It's to with oscillation (harmonic flexure) of the crankshaft that exists with all engines regardless of how good the rotational balance is (or isn't). A rule of thumb is that the longer the crank the more likely it is to flex significantly at certain rpm (and lower rpm).

Simplistically, for each crank revolution there are two strong power strokes that create a force with the crank that causes flexure of the crank, and these flexures have a harmonic nature that at differing points in the rpm range excacerbate the strength of the flexure. The damper reduces the severity of the harmonic oscillation and thus the degree to which the crank flexes at certain critical rpm, but the damper doesn't eliminate the oscillation.

[johnl]

Its there to help absorb shock. And an engine cannot be 100% internally balanced over time. Parts wear out.

Wear doesn't affect balance to any significant degree.

All that 'internal balance' means is that each rotational component is individually balanced prior to assembly, as opposed to 'Detroit' balance, where the assembly as a whole is crudely (read cheaply) balanced by means of removing weight at a strategic point on the flywheel after the rotational components have been assembled.

[BigBlueVan69]

This JUST happened to me. The belt fell off and the crank pulley is super loose now, but the car still runs even with the alternator belt off. So I should replace the crank pulley?

[Granite CB7]

^Definitely, asap, the car is running right off the battery. It'll be fine for alittle while, but get that fixed, you're going to need the alt. operational.

[BigBlueVan69]

Yeah, too bad I had to pay all of my bills today. Good thing I only work 1.5 miles away. Looks like I am huffin it for a while. Can my P/S rack dry up and lock without P/S fluid in it?

[Granite CB7]

It is good you are very close, just remember to keep the battery's drain to a minimum-no radio, no heat/cc, no lights if you can help it. I've seen decent OEM crank pullies @ junkyards before, just a though since money's tight. OEM Honda is best though for crank pullies. About the p/s rack, you're fine, the whole system is filled, you're just pushing the fluid around by hand when you steer.

[BigBlueVan69]

Yeah, but it leaks hahaha. Forgot to mention that. Yeah I would never use an aftermarket pulley on a daily like this car. Gotta save money to put the K in my sedan.

[johnl]

Never use an aftermarket pulley if it doesn't incorporate a properly engineered harmonic damper. Personally I wouldn't trust anything other than the OE unit, especially if the engine ever sees the top end of the rev range. In this instance lighter is not better...