Hey guys,

I've had this chatter/rattle on start up for what seems like forever, at least since the winter of 2012!

The noise is from the front of the engine - the first time I heard it was when I was showing off the car to an old mechanic friend of mine. He said "a lot of them do that" and "just squirt some wd40 around the front of the motor and that should fix it", so squirt I did and yes the noise disappeared. The "remedy" lasts about a week then it starts again.

It only ever makes the noise when the car is cold - in the summer months it disappears.

At first I thought it was the timing chain slapping about and then the harmonic balancer but as the wd40 thing stops it in it's tracks, I think it must have to do with the belts (and I know, don't spray wd40 on the belts etc).

The noise is not what I'd say is a typical slipping belt squeal, but more of a metallic clang-squeak sound that's roughly in time with the revs. Goes away when car warms up.

Anybody else had this problem or have an idea what's causing it?


Larry

 

Waterpump bearing. top front of the engine. Very likely.

Locating the origin of engine noise is best done using a small tube. place one end to your ear, and scan suspected areas with other end.

 

Hi Larry,

It sure sounds like the classic upper timing chain rattle before the hydraulic tensioner refills with oil pressure. Our '93 behaves the same way and I've been intending to pull the tensioner to see if I could improve things by replacing the O-rings. Shouldn't be difficult, just another thing on a very long list.

I can't explain why spraying WD40 would quiet things down but on our '93 the clatter goes away pretty quickly on its own, and if you shut off the engine and restart it, there's no clatter, presumably because the tensioner retains its pressure.

I suppose the water pump bearing is a possibility as Wilfred mentions, but in my experience a bad one produces more of a squeal than a rattle or chatter. Easy enough to listen to with the tube Wilfred suggests or with an inexpensive mechanics stethoscope.

Cheers,

Don

 

Hi Don, I'm baffled why a quick mist of wd40 sprayed down near the a/c compressor would immediately stop the rattle if it is indeed the timing chain????

Larry

 

Could it be a worn A/C compressor clutch/pulley that is rattling? The A/C won't start up immediately until the Climate Control Microprocessor gives it the green light (the ECM may also delay the CCM from engaging the compressor clutch for a little while after startup - I can't recall for certain). Is it possible that what you're hearing is internal parts of the clutch rattling from the movement of the pulley?

 

I think it might be something like that Don. Difficult to pinpoint though ..

Larry

 

You could temporarily remove the AC compressor belt to see if the noise goes away.

 

Good thinking!

cheers Don


Larry

 

Hey Larry,have you found the cause of your noise?

If it is the AC pump doing the bad thing,I am going to pull all the AC stuff off Cin's Champ car in search of better mileage.

I will pull the radiator and stuff out to replace the support bushings,hoses,oil press. sender,and related goodies,so if you need parts........

Cheers,Jim.

 

Hi Jim, The noise hasn't returned since the weather warmed back up so haven't had a chance to suss it out - no doubt this warm spell won't last too long so I'll report back later on that ...

Thanks for the offer on the parts though - don't toss anything out in the meantime!

all the best to you and Cin for Xmas!

stay dirty,

Larry