W123 noise?
 

Hey everyone,

So my w123 is making a strange noise on cold starts.

It's a loud whirring noise, almost a hollow whistling, if that make any sense?

I'm wondering if it's a fan clutch?

There are no mechanical symptoms, just the noise.

But it is concerning.

I'm getting ready for a 12hr round trip and I was planning on taking the w123 but now I'm a little worried.

Any ideas?

Vacuum pump?

Sixto
87 300D

Cruise control actuator? Mine randomly comes on sometimes and makes a noise similar to what's described in the OP.

Cruise control has been removed, maybe the vac pump?

The car has been slow on shutting off after I turn the key....

I'd definitely rule out that vacuum pump first as suggested by sixto.

Could even be a leaky vacuum connector, hose or vacuum fuel cutoff as you mention it's slow to shutoff.

Divide and conquer! MightyVac time.

Starter bendix failure...

Technically speaking, there is no Bendix in the W123 starters. Bendix type starters were phased out in the 60's. The Bosch starter is an over-running clutch type with a solenoid and a lever to engage a pinion gear on a one way clutch, which drives the ring gear. The solenoid also operate a high current contactor which supply juice to the starter motor.

Could it be your tach magnetic pickup hitting the pin on the harmonic balancer?:D

This can be dangerous for your teeth! But sometimes gripping one end of a screwdriver in your mouth and placing the other end against a bit of the engine that isn't moving but close to where you think the whirring is coming from can help. Be careful.


And I'll say it again be careful.

but the whirring could give itself away in the form of vibration that will transmit through your skull to your ears and will sound louder than before.

Don't do this for too long - you could not only damage your teeth but your hearing.


(This is a cheap mechanic's stethoscope)

The problem is the car doesn't make the noise idling or if I rev the engine idling,

It really only starts when the car is moving.

There are some messed up connections in the vac lines that I will photograph and post.

It's not related to the new tachometer because it's been making the noise for a long time.

I'll post photos in a few.

Ah ha when it is moving... do you get a change in whirring with the clutch depressed?

No change clutch in or out.

Are you thinking pilot bearing, Army?

Sixto
87 300D

Open connections in Vac system.

On the first picture there is a completely open connection, not sure if this is a problem or not?

On the first picture I'm holding a woven hose, and it's all cracked around the base so that is certainly not airtight.

On the second picture, you can see where the woven hose connects on the otherside of the engine, again, it's cracked around the base so it's not an airtight connection.

Not sure if either of these would have ANYTHING to do with the whirring noise.

btw, the second picture is just above the alternator and has a hose connected to the radiator, i'm not sure what it's called.

I was thinking perhaps clutch release bearing or gearbox lay shaft bearings - obviously not the gearbox bearings though if the clutch position makes no difference...

Ya Mar - can you make a film with sound recording of the whirring noise? We're guessing at stuff all over the place - we need some help to help you.

Question
 

Is this a better description of your issue?

It's a loud whirring noise, almost a hollow whistling on cold starts when the car is moving.

At 1min 30 seconds you can start hearing it well.

whunter, that is a good description, which is why I thought it might be a fan clutch as per a posting I found with a good search. Not sure though, since the sound persists whether the clutch is in or out.

Video is here: http://www.youtube.com/watch?v=cnW2N60n5ek

Which type of MityVac do I need for testing out the vac system?

I'm having slow shut offs, and I can only lock the doors when the engine is running.

I listened to the youtube video and didn't hear any weird noise while you were accelerating; only when you began to slow down during the last half of the video did I hear a whistling sound.

It sounded to me almost as if wind was blowing across a hole and kind of harmonizing with some part of the car.

Hey, the video wasn't that great, but that noise does happen during acceleration, coasting, and deceleration.

But it goes away when the engine is hot, 10min or less.

The noise at around 1 min 30 sec into the video is the sound.

As I accelerate it becomes louder and higher pitched, then it will stop abruptly. Be quiet for a few moments, and randomly start up again.

I think that sounds like a driven bearing problem - like say a propshaft bearing...

Have you been able to sit in different positions in the car (with someone else driving!) to identify where the sound is coming from?

I haven't sat in other positions in the car but it sounds like it's coming from deep within the center front of the engine area. Perhaps just behind the engine around the transmission.

Drove the car today in 80 degree temps and it made no noise despite the cold start.

So I can conclude:

Only makes noise on cold starts when wet or cold!