Bronze Spigot Bush

[smclaren]

Hey Guys
So I am dealing with a gearbox/clutch noise that I am suspecting is the bronze spigot bush.
Has anyone dealt with a noisy spigot bush before ?
What sort of noise did it make ... and under what conditions (clutch/gear selection movements etc) was it misbehaving ?
Cheers, Steve

NR009-48-3.jpg (79.71 KiB) Viewed 68 times

[Blacky]

Never had an issue but quite often you see a discussion about these and people say put a smear of grease in them when you install a gearbox - from what I have been told that is incorrect you should only put oil on them as the material is porous and the grease will it and it will run dry

[ardiesse]

Steve,

As Blacky says. Leave the bush in engine oil for a day before installation. Don't use grease.

Spigot bushes almost never give trouble. And the sintered bronze bushes are quiet in operation. So tell us what the clutch/gearbox noise is, and we'll do our best to diagnose it. Apart from the engineered-in "nacka-nacka" sound of clutch shudder -

Example 1: A weird whirring, almost howling sound just as the clutch begins to engage. If the driven plate splines have excess clearance on the gearbox input shaft, the clutch plate can wobble, and it chatters between the flywheel and pressure plate faces. Clutch replacement's the only option here, hopefully with a more closely toleranced driven plate hub.

Example 2: A brief, high-pitched "eeek" just as you begin to push down on the clutch pedal. This is the throwout bearing contacting the diaphragm spring fingers. It's too much work to drop the gearbox just to put grease on the fingers, so live with it.

Example 3: A whirring sound when the clutch is disengaged. Throwout bearing troubles.

Example 4: A gentle "shhhh" sound in neutral. Indicates gearbox bearing troubles: input shaft ball bearing, cluster gear needle roller bearings.

Example 5: A low-pitched whirring sound when accelerating through 30 mph in top gear. Gearbox mainshaft bearing noisy.

Does the noise happen when the engine's stopped? In this case it's to do with the slave cylinder, clutch fork, or (very occasionally) the pressure plate diaphragm spring pivots.

Rob

[smclaren]

Cheers Guys

Yep, aware of the "correct" lubrication of the bush (soaking in light machine oil) .. it's well spelt out in the manual ... but not saying that I've actually always FOLLOWED said instructions though ... but I've personally never had a spigot issue either ... ever ... hence the question.

Definitely not a thrust bearing, and not a gear noise .. familiar with those those over the years.

Specifically for you, Rob ... its a loud groan-ish noise (GRRrrrRRRRrrr) as a gear (first or reverse) is selected at standing idle. It's definitely not a gear grind. It's also intermittent .... the most fun of all issues to diagnose.

So no noise at idle or at idle with clutch peddle in. Noise appears (GROAN) as selector picks up a gear ... and disappears when clutch peddle is released and the tension of the load is introduced into the drivetrain. Noise does not appear whilst driving, or changing gear whilst in motion.

I have noticed that if I remain stationary and can get the noise to appear (so stationary, clutch in, select gear, GROAN) I can knock it out of gear with the clutch still in, and the noise will continue on for a second or so. It will dissipate by its self after a second or two ... or if I release the clutch.

My money is on the bronze bush.

Is this what "Telehealth" is like .... asking for a friend ?

[ardiesse]

Steve,

I'm thinking that you have an instance of Example 1: driven plate chatter.

Try this out: When stationary, at idle, when you go to select a gear and the groaning noise happens, turn the ignition off *without releasing the clutch*. If the groaning noise stops immediately, you have a chattering driven plate.

The noise doesn't appear in neutral with the clutch released - possibly because there's enough residual friction to make the clutch plate turn, so it doesn't chatter. Then when you go to engage a gear, the clutch is held still, and this is when the chatter happens.

Another thing you can do: find a gentle slope nearby and pretend you're going to clutch-start the car, but with the ignition off. Try it in second gear, at about walking speed. Let the clutch out enough to slow the car, but not enough to make the engine turn over. Here there should be no noise, except maybe for a gentle "shhh" of the clutch slipping.

Rob