crank bolt right or left hand thread?

interesting. do you have any thoughts on the fact that it has an "harmonic balancer" also? they do a lot to reduce rotational inertia which might tighten a bolt in one direction, but loosen in another. for a balanced crank and flywheel, there's really isn't a lot something low mass like this can achieve vibrationally. besides, hondas run successfully without them, so i wonder about its actual purpose.

possible, but that doesn't explain the discrepancy between the galling being present on the pre-92 vehicles and there being none on the later ones.

is the pulley wheel splined? you don't state the vehicle's age.

"Burt" wrote

What model is this?

I know the 84-87 Civics have an 83 ft-lb pulley bolt spec, but some have a 2.9L engine?

Little discrepancy that we should clear up to make sure we're on the same page.

Did you also try to break the bolt free? If so, any estimate of how much torque was needed?

Thank you for doing this.

The purpose is to transfer US $100+ from my pocket to Volvo's coffers occasionally (the first lasted about 150K miles). For those trying to picture this device, imagine your crank pulley with a strip of rubber running the circumference and bonding the pulley part to the core. The rubber eventually shears....

For whatever reason, the B230 engine has a harmonic balancer - also called a harmonic damper... not sure which term is official - while the very similar B23 engine has a conventional pulley. Hmm.

Mike

it does indeed!

which is even more interesting. it definitely will damp the rotational inertia spikes that will transient between the crank and those rotating masses the pulley drives.

"jim beam" wrote

The galling was probably caused by the lack of a vibration damper. At best guess, the 92 Accord's balancer shaft may have helped. This and the high bolt torque, 160-lbft, may explain why the galling isn't present on the post-92 Accords, which I've also witnessed myself.

88 Accord...no spline.

"jim beam" wrote

Successful? What about the galling on the crank bolt head you've talked about. That could've been caused by the torque pulsation of the vibrating engine.

Take for instance, when ever I do a brake lathe without the vibration damper on the brake disc there is a wave effect on the surface. On the crankshaft, these wave (oscillating) effects can transfer eat up the transmission gears or various parts.

"Elle" wrote

88 Accord, around 286k miles.

Yes, I could break it loose but I'd just broke loose the 92 Accord engine block coolant drain bolt today which took about 150-lbft and pretty exhausted.

Tell you what, tommorow I will:

1. Hook up a beam torque wrench to a chain hoist horizontally and slowly chart the effects during unbolting.
2. Do the same to my other 92 Accord.
3. Both cars will be torque and loosen and chart the difference.
4. Both cars will be marked before loosening.

There is a problem with #1. My beam torque wrench only goes to 150 ft-lb, which is design for head work only. I have a clicker type rated at 200-lbft, but this is inconvenient. Other than this, what would be another practical way to measure the loosening torque?

Your welcome.

:-)

That's the other one that's a bear for the home mechanic, as you may have heard.

I will say that my coolant block bolt was only tough the very first time I freed it.

I appreciate your enthusiasm, but I don't think doing a careful check of the "break free" torque will reveal anything new. We all already know that after several years and many miles of driving, the bolt becomes very tight.

If your Accord's pulley bolt is not very tight, then this just suggests (to me) little time has transpired since it was last freed.

There are some other suppositions that one can make, but I don't care to venture into what may be fantasy land.

It certainly could be simply "cold welding" of this fine threaded bolt subjected to terrific dynamic loads and temperature variations.

"Elle" wrote

As you've probably known, the bolt has a very shallow head. This was the main problem. I had to build a jig to steady the tool. After some thought the jig was nothing but two blocks of wood (a 2x4 and a 2x1) and it was freed easily. :~)

I see. But looks like I do this at a later time. I'd set up the chain come-along but I can't locate a buddy of mine who has a 5-ton crane scale.

The 88 Accord pulley bolt which I believe had driven some

80k miles before the belt was changed was loosen easily. The 92 Accord was driven about the same miles but the bolt needed help from a machine.

After 375k I've done a bunch. It was a bitch the first time and it was a bitch the most recent time. In all cases the usual 250ish foot-pound impact wrench on a quarter-inch hose wouldn't budge it, though I wasn't willing to spend all day on it before breaking out the big guns.