[JoshV12345]

Hi all,

I have a 1977 Alfetta and every now and then a funny noise comes from the front drive shaft region. It sounds like very light metal on metal contact.
Sometimes this noise will last for a long time and other times it will only last for a few seconds. The noise is quite loud, it can be heard a fair way away from the car.

All of the donuts have been replaced, also the engine mounts (including the rear one).

Could something i.e. the donut bolts etc, be hitting on the bell housing?

After the mounts were changed the motor has visibly moved. The noise doesn't get worse when the engine is cold and running a bit rough. In fact, it usually doesn't appear until I have driven it a little bit.

What puzzles me is that I have no idea what it is, whenever I get it up on the hoist to have a look, the noise magically disappears. I've had a good look at the front donut and I can't see any signs that it is touching anything.

Any insight would be greatly appreciated...Thanks

 

[ghnl]

Are there any heat shields? If loose or bent they can vibrate causing mysterious noises.

 

[giamba_ps]

shift linkage , play in the shift linkage bushings..... and the shift lever , some times they "sag" because the retainer bushing wears on the bottom of the shift lever , and in some positions it can actually hit or rub the drive shaft. look see if this is the prob.

 

[ossodiseppia]

If it's a swishing or scraping like sound it's more than likely one or both slingers on either side of the carrier bearings. They are either improperly installed or slightly bent.

 

[JoshV12345]

Thanks for the replies.

Eric, the heat shield was taken off and never put back on so that's not it. I thought it might've been the exhaust hitting on something but I've played around with it while it's running and I can never get the noise to start/stop.

Giamba_ps, I'll check that out again but I'm pretty sure it's not hitting. I've been under the car while it's running and there's no sign that it's hitting. If the linkage is moved all the way to the right (near 5th and reverse) you would assume it would be far enough away to stop making any contact?

Ossodiseppia, could you elaborate on this 'slinger' I've never heard of it/them before. Not sure if it's a 'scraping' sound it's more like getting a screwdriver or bit of metal bar and tapping on another bit of metal, not really a scraping kind of sound, it speeds up as the engine speeds up. The only thing I can think it sounds close to is a loose tappet. It's not exactly like that but it's close.

 

[alfasrule]

Dude you gotta drive one of these things when it's -15F!! It's like a car going through a crusher!!! But ya know she get me to work everyday like a good Alfa should. I've found my exhaust clamps were not tight enough, from front to mid took quite a while to find cause it would only happen once in a while. Just a suggestion.

 

[ossodiseppia]

.....After the mounts were changed the motor has visibly moved...

I missed this comment the first time I read your post. It's a little disconcerting. Can you please elaborate on this?

I did the motor mounts in my Alfetta more than 25 years ago. So, I can't remember if it's possible to get them swapped around on install. Can anybody comment on that?

Ossodiseppia, could you elaborate on this 'slinger' I've never heard of it/them before. Not sure if it's a 'scraping' sound it's more like getting a screwdriver or bit of metal bar and tapping on another bit of metal, not really a scraping kind of sound, it speeds up as the engine speeds up. The only thing I can think it sounds close to is a loose tappet. It's not exactly like that but it's close.

The slinger is a round, concave shaped bit that mounts on one side of the carrier bearing. See the attachment. It's part number 11600.15132.02. If it gets bent during installation, it can scrape against the center support.

If you think it's a lose tappet, that should be fairly easy for you to identify. Old school mechanics use screw drivers as a stethoscope. Take a flat-head screw driver and put the business end of it down on the valve cover. Put your ear to the handle and listen. I typically, I put the handle just in front of my ear opening. The screw driver should transmit the sounds to your ear.

I am not familiar with the sounds of piston slap or rod knock, but those are a possibility too.

I think the best approach is to work backwards. Did this issue start right after the drive line and engine mounts were serviced? If so, then we probably need to focus on them first.

Let's get some pictures of the engine bay and see if others, with a better eye than me can see anything. Also, some pictures of the carrier bearing mount and front and rear donuts would be great.

 

[JoshV12345]

I missed this comment the first time I read your post. It's a little disconcerting. Can you please elaborate on this?

Ok well what happened was when the rear mount was being taken out the bell housing cracked so I had to find another one which I did from an identical car. The housings looked identical when I compared them. After putting the new mount in and then putting the housing back on I thought it would be a good idea to change the other mounts because the motor was out anyway so it would be less stuffing around in the long run because the old ones looked pretty rooted.

When putting the motor back in the two main mounts lined up but the rear one didn't exactly but it was still possible to get it onto the bolts.

(As you can see from the photo it was extremely difficult to get the nuts on these bolts because they just started spinning so one side I had to put spacers etc on and the other side the bolt was nearly all stripped so I managed to get it on and tightened it by prying the mount down with a screw driver to stop the bolt spinning.)

I did the motor mounts in my Alfetta more than 25 years ago. So, I can't remember if it's possible to get them swapped around on install. Can anybody comment on that?

They are different, the one on the carby side has the support bracket bolted to it.

The slinger is a round, concave shaped bit that mounts on one side of the carrier bearing. See the attachment. It's part number 11600.15132.02. If it gets bent during installation, it can scrape against the center support.

The centre bearing was not changed when the donuts were changed so I don't know how it could have become bent but it could be possible I suppose. The noise does not seem to be coming from there though it's more like right up the front of the driveshaft. The noise could be reverberating and making it seem like it's coming from a different direction though :S

If you think it's a lose tappet, that should be fairly easy for you to identify.

The motor does have a loose tappet, I know this already (I don't have the money right now to get a shim kit or the time to do it for that matter). The noise I'm hearing is different, it comes and goes and is distinctly audible over the top of the tappet noise.

I think the best approach is to work backwards. Did this issue start right after the drive line and engine mounts were serviced? If so, then we probably need to focus on them first.

Well this is where it gets confusing...if it was a bent slinger the noise would be there as soon as I started it up for the first time right? I was driving it for quite a while by which I mean a few thousand klms before this noise started being a problem. It's becoming more concerning now because the noise used to happen very rarely i.e. not even once every few weeks and would only last a few seconds. But recently it's started making it all the time. I'll start it up cold one morning and it'll idle for about a minute and then the noise will start and won't go away. If left idling it sometimes goes away after a while but always comes back when you start driving. There is also no excess vibration.

I've attached some photos, most of the driveshaft are blurry and can't see much because I was trying to take photos whilst squeezed underneath. It will be a few days before I can get it up in the air to take some proper photos, I apologise for that.

Thanks for your help.

 

[JoshV12345]

Some more pictures I attached a photo of the whole motor so you can see if it looks to be on a weird angle. To me it looks the same as before the mounts were changed...

 

[La Voce]

Wow

Serious alignment issues evident in the photos. For a big start, you're missing the rear engine mount spacers between the mount and frame.That is why you needed the washer stackup to make it work.

 

[La Voce]

Added for clarification...

 

[ossodiseppia]

Good eye there, Jim. It does look like there may not be enough shims on the rear mount. Do you think that's enough to cause those motor mounts to be pulled back so much?

I suppose the thing to do would be to drop the back of the bell housing down and see how that affects the motor mounts. If you drop it down about as much as the thickness of one of those nuts, will it take some of the twist out of those motor mounts?

The noise has probably been getting worse because the front bushing (11600.15194.09) is wearing. That drive shaft needs to be properly aligned or it gets really unhappy. As far as I know, those bushings are no longer available. So, you want to make sure that you don't ruin it or you'll have to get a new (to you) drive shaft. I would not continue to drive that car in it's present condition as it will cause more wear and tear on the bushings and bearings on that drive shaft.

It looks like there is only one bell housing for the euro Alfettas. According to the parts manual, it's used on the 1600 and 1800 sedans as well as the 1600, 1800 and 2000 GTs. The US version Alfettas used a different one. I don't know what the difference is.

 

[La Voce]

Actually no

I can't see a relationship between that obvious rearward pull on the motor mounts and the missing collars.

 

[Alfaguy35]

Motor mounts

If I'm looking at those pictures correctly the motor is forward on the intake side and backwards on the exhaust side. That would mean the the rear mount is offset to the right, so not only is the motor too high in back because of the missing spacers it is off to the right. I'm guessing that someone installed a GTV6/Milano rear engine mount in the car as Alfetta ones are very hard to find. The GTV6/Milano mount is offset to one side. Take a look at the ears that come out of the mount. They should be the same length on each side.

 

[JoshV12345]

For a big start, you're missing the rear engine mount spacers between the mount and frame.That is why you needed the washer stackup to make it work.

Ok that's good to know...when I took the old mount off there was no spacers there so I was unaware that there had to be. Do you happen to know what thickness they need to be?

It looks like there is only one bell housing for the euro Alfettas. According to the parts manual, it's used on the 1600 and 1800 sedans as well as the 1600, 1800 and 2000 GTs. The US version Alfettas used a different one. I don't know what the difference is.

It was off one of these cars mentioned as far as I know...it definitely wouldn't be off a US car.

I suppose the thing to do would be to drop the back of the bell housing down and see how that affects the motor mounts. If you drop it down about as much as the thickness of one of those nuts, will it take some of the twist out of those motor mounts?

Ok I'll look into that as soon as possible. It was more of a left/right alignment issue not front/back.

Is is possible to start it up after I've undone the rear mount? Just to see if the noise has gone. Because then I'll know that that was the problem...

If I'm looking at those pictures correctly the motor is forward on the intake side and backwards on the exhaust side.

Yeah that's exactly the problem...but the mount is the same length on each side so I can try hitting it through a little more to see if that takes some of the twist out. Can anyone suggest an easy way to move that mount? I've heard that heating up the outer housing helps but I don't think I have access to anything that will do that. Also, what do I use to hit the sides with?

 

[La Voce]

Josh the shop manuals I have don't list the height of the collar, the only way for me to determine it would be for me lift my car and crawl underneath and measure one but that's not possible today. I would guess they are about 12mm; if you were to use one nut and a washer between the mount and frame that would be an improvement over the setup you have now until you can source them.
Regarding your alignment problem along the longitudinal axis of the car, can you take photos of your De Dion tube where it mounts to the car, front and rear, including the Watts linkages, your tranmission mounts, and post them?

Regarding your noise. Have you carefully looked for signs of metal-to-metal contact all along the drive line? I recommend you crawl under the car and inspect all eight flywheel mounting bolts. If one has vibrated loose and backed out its head can contact the front flex coupling mounting studs that are pressed through the flywheel as the prop rotates. This can shear the head off the bolt, then you're in for some real time and money. You'll need a flashlight and a 17mm wrench to rotate the prop shaft.
Good luck!

 

[JoshV12345]

Regarding your alignment problem along the longitudinal axis of the car, can you take photos of your De Dion tube where it mounts to the car, front and rear, including the Watts linkages, your tranmission mounts, and post them?

Yes I can, probably won't be until tomorrow though (it's night time where I am now).

Josh the shop manuals I have don't list the height of the collar, the only way for me to determine it would be for me lift my car and crawl underneath and measure one but that's not possible today. I would guess they are about 12mm

That's ok, I'll get something that will do the job and make it approx. 12mm... I think right now the more important issue is getting the twist out of the motor.

Have you carefully looked for signs of metal-to-metal contact all along the drive line?

Yes, I have carefully gone over the driveshaft but I didn't check the flywheel bolts, I'll do that tomorrow as well. Those bolts can be accessed without removing the driveshaft, yes?

 

[La Voce]

Yes, from under the car you can see your Alfetta's flywheel bolts without removing anything.

 

[Alfaguy35]

Rear motor mount

The GTV6/Milano mount is offset to one side. Take a look at the ears that come out of the mount. They should be the same length on each side.

That was incorrect info. I just measured the rear motor mount from the Lemons car we parted out and the mount is offset. The passenger side measures roughly 2" to the center of the mounting hole and the left side is about 1 3/4" to the center of the hole. I have a complete bellhousing with a reinforced mount for sale if you want it.

 

[ossodiseppia]

That was incorrect info. I just measured the rear motor mount from the Lemons car we parted out and the mount is offset. The passenger side measures roughly 2" to the center of the mounting hole and the left side is about 1 3/4" to the center of the hole. I have a complete bellhousing with a reinforced mount for sale if you want it.

The bell housing for the US cars is different than the Euro cars.