Rattling Belt? Something Worse?

Youtube diagnosis, always accurate

Sounds mechanical, not a belt.
I wouldnt be running that engine though - could be very loose cam chain, valve problem, broken drive key for the brake vacuum pump and many other things. With the bonnet open and a stethoscope you could narrow it down quite a bit.

Looks like its in a dealership, what to they say ?

M

 

Well, a loose fan belt would be easy to check. Just try pushing on them. It could be a loose cam chain.

 

I hope they don't think there are "fan" belts as such - the fans are electric fans.
There are dual belts for the A/C compressor ( and the rattle could be coming from the compressor, didn't think of that ) dual belts for the power steering pump and a belt for each alternator (there are 2 alternators) . Adjusting or replacing the belts takes a bit of time, bit like a Rubiks cube, needs to be done in the right order

M

 

I had a very similar noise in my 1982 400. I thought chain, idler, or worse. I used an electronic stethascope and could not pinpoint the noise any closer than the lefthad front side of the motor around the timing chain case.

On a whim I grabbed a can of belt dressing and sprayed the alternator belt and the noise dissapeared. I replaced both alternator belts with new cogged back belts and no more noise.

just sayin'

Howard Musolf
1981 308gtsi
1982 400i Cabriolet
1994 348 spyder

 

This is what it sounds like to me without actually being there. There are two thin belts driving the alternators (and for the PS as well as the AC but the alternator belts seem to be the culprits most of the time) and they can be noisy with a loud ticking or clacking sound, almost like electrical "snapping", if the car is not driven regularly, possibly because the rubber stiffens or hardens with age and takes a set in the position that it has been sitting in. This is the sound that the belts on my car made when I bought it and it had been driven only 4,000 miles in 10 years in southern California.

Sometimes it goes away after a few minutes and the belts have warmed up but I suppose in cases where the rubber in the belt has hardened, it persists for a while. People have achieved a temporary fix by spraying with WD40 or even water but I think that the main problem is that they are due for replacement.

All of the belts are inexpensive to buy, a bit of a pain to replace, particularly the lower alternator belt, but that should solve the problem. Just keep track of which belt is which because they have different sizes and part numbers but look very close in size. If you mix them up you will go crazy trying to get them sorted out.

 

+1 on the Alt. belts, go there 1st

 

A chattering V belt can make some ominous sounds, perhaps this it. If the dealer is convinced it is this simple he ought to be able to correct it in a flash. Telling of his used car prep beyond a wash.
A bar of soap against the sides of the belt will provide enough lubrication to stop the chatter until a fresh belt can be installed. It's NOT a tension issue, the belt(if indeed the source)is either old and hard or glazed.

 

If you buy this car, or need a PPI, I would take it to Bill Pollard (Sport Auto) in Gaylordsville, Connecticut.

Aidan

 

Hi Robert,
I have a 1988 412 with little mileage (less than 10.000 km) which makes a similar noise at start for about 5 minutes, then that noise goes away. Same for a 1983 400i (78.000 km). I was told that the noise comes from the belts. I will make a video for these cars at start and post the video.

Regarding the wheels of that 412, they look very similar to the wheels on the car shown in the following post:
https://www.ferrarichat.com/forum/365-gt4-2-2-400-412/419002-anyone-know-these-wheels-car.html

Would you have information about brand/type/size of the wheels on the 412 in the video?
Thanks in advance

 

Riiight,having checked out all the replies to this thread(and wondering what actual noise you are all talking about),I am thinking it's the 'crackling 'type sound???
My 365 makes it when cold as does a C4 owner's car,my mechanic says it's normal for them to make the noise.
Unsure if the 400/412 does the same.
Just got off the phone from Marc re this,if it's the crackling noise,it's the drive belts,early in the morning,if they have some 'sheen' on them it happens,it also happens on 308's,apparently.

My car has always made this noise since purchase,it hasn't affected it's performance at all........................................it'll still drag the pants off any 400......................................




......running...

 

+365

If its a ticking/cracking sound on start up that goes away once the engine is warmish, its the alternator belt. I have a brand new engine and it still does it occasionally

 

The problem was discussed a year ago in the following post:

http://www.ferrarichat.com/forum/365-gt4-2-2-400-412/366976-clicking-noise-alternator-belt.html

I had the same problem on my 412 and fixed it temporally with WD40. This spring I changed all the belts and noise problem was gone.

 

What repair work can you do on your own? Chances are good that any car for sale will have immediate needs. I'd start with only looking at colors and models that appeal to you then work up a list of repairs.

 

Hi Santos,
Do you have the details for the wheels installed on this 412 (rim and tyre nature and size)?
Thanks in advance