This sound is driving me nuts

[digitalzed]

Just two days ago my '78 450 SEL began making this kind of clinking/cranking/rotating sound coming from what seems to be under the the car, almost in the middle. Just about dead center between the driver/passenger seats and rear seat. I know it's a long shot that anyone might have an idea without hearing it, but I thought I would ask here. I am going to take it to be looked at next week, but thought someone might have an idea?

Don't drill me for posting an impossible question! You never know, someone might have an idea!

 

[BAR]

Universal Joint?
Drive Shaft coupler?
Harmonic Balancer?
Loose exhaust clamp?
Gearbox?

Better desctription of noise may focus the responses.

 

[John S]

Slide under the car and grab the drive shaft, forward of the centre support - push up and down. Any movement and it's normally the centre bearing support rubber that needs replacing. Not expensive.

 

[BenzLover]

Would it be that your guide rod is due for replacement?

 

[TJ 450]

Would it be that your guide rod is due for replacement?

The guide rod was introduced on the W123, with the W126 using a similar setup. The W116 has a one-piece lower control arm.

Tim

 

[digitalzed]

JohnS: Will do.

TJ450: Thanks for clarifying!

BenzLover: Whew!

 

[Styria]

Can anyone tell me what a guide rod is ? I have never heard of that term being referred to. Sorry ! Anyway, Digitalzed, such prominent noises as you describe do not, or should not, happen from one night to the next day. You do invariably get some warning or ongoing noise.

Thus, I'd look at the exhaust system (the rubber hangers) first, then a collapsed centre bearing mount (as per JohnS), and then start looking at the propshaft front and rear couplings and last, but not least, the gearbox mount. Excessive drippageof oil from the gearbox (and other components), will soon play havoc with rubber mounts and bushes. I know - just ask Gleaming Beauty (my 6.9). Regards Styria

 

[BenzLover]

Can anyone tell me what a guide rod is ? I have never heard of that term being referred to. Sorry ! Anyway, Digitalzed, such prominent noises as you describe do not, or should not, happen from one night to the next day. You do invariably get some warning or ongoing noise.

Thus, I'd look at the exhaust system (the rubber hangers) first, then a collapsed centre bearing mount (as per JohnS), and then start looking at the propshaft front and rear couplings and last, but not least, the gearbox mount. Excessive drippageof oil from the gearbox (and other components), will soon play havoc with rubber mounts and bushes. I know - just ask Gleaming Beauty (my 6.9). Regards Styria

Here you go Styria a few links for you.


http://www.peachparts.com/shopforum/showthread.php?t=170478&highlight=guide+rod+bushing


Cheers
Big Dan
Vancouver Canada>>>>>Soon in Kyogle NSW

 

[digitalzed]

Can anyone tell me what a guide rod is ? I have never heard of that term being referred to. Sorry ! Anyway, Digitalzed, such prominent noises as you describe do not, or should not, happen from one night to the next day. You do invariably get some warning or ongoing noise.

Thus, I'd look at the exhaust system (the rubber hangers) first, then a collapsed centre bearing mount (as per JohnS), and then start looking at the propshaft front and rear couplings and last, but not least, the gearbox mount. Excessive drippageof oil from the gearbox (and other components), will soon play havoc with rubber mounts and bushes. I know - just ask Gleaming Beauty (my 6.9). Regards Styria

Thanks Styria,

I've had the car about 2 months and the other day really was the first time. I've been keenly aware of any changes I feel or hear when starting and driving the car. The did go in for a B type service at a reputable indie a few days before this started. I am not saying they did anything. There have been some small (dime sized) spots of oil leaking. Literally one every time the car is parked.

 

[Styria]

Thanks for the links, BenzLover. I guess you learn something new every day - I have always known that part to be referred as the lower suspension link.

It was interesting to read of someone's referral to the removal of the large eccentric bolt - always fairly easy until you get stuck with the situation when the bolt is rusted onto the metal part of the bush - boy, is that then some fun to remove. I have actually had to have some cut out with an oxy.

Digitalzed - I don't think the guide rod is your problem. That'd give you plenty of warning. Be interesting to find out from you in the end what your problem is or, for that matter, will have been. Regards Styria

 

[digitalzed]

Styria, I will let you know. In it goes to the wrench tomorrow.

 

[digitalzed]

Oddly enough, it turns out it was the catalytic converter going out. Thanks to everyone who tried to help. Should have the car back later today.

 

[s class]

........removal of the large eccentric bolt - always fairly easy until you get stuck with the situation when the bolt is rusted onto the metal part of the bush - boy, is that then some fun to remove. I have actually had to have some cut out with an oxy.........

I've just been through this on the dark blue project 6.9 this last weekend. I now have the lower control arms separated from the subframe, but I still need to press the remains of the bushes out. Boy, it's taken some time and sufferance.

 

[John S]

When did they start using catalytic converters in the W116 series?

 

[digitalzed]

When did they start using catalytic converters in the W116 series?

California made it a law in 1976, the USA followed in 1978, and Europe shortly thereafter.

 

[OzBenzHead]

California made it a law in 1976, the USA followed in 1978, and Europe shortly thereafter.

My 116 (280SE) is a Euro version (privately imported to Australia after spending its first five years in the UK, where it was sold new). It was manufactured in December 1979 and had no anti-pollution measures fitted (they are neither obvious, removed, nor noted on the data card). Australian-market versions had air pumps and similar crap attachments from 1977 or '78, I believe.

 

[digitalzed]

My 116 (280SE) is a Euro version (privately imported to Australia after spending its first five years in the UK, where it was sold new). It was manufactured in December 1979 and had no anti-pollution measures fitted (they are neither obvious, removed, nor noted on the data card). Australian-market versions had air pumps and similar crap attachments from 1977 or '78, I believe.

Sorry, "shortly thereafter" is a relative term. Perhaps "sometime after" would have been better wording. I have no idea when each European country made it law to have whatever anti-pollution devices put on their cars. By what you say, it appears the UK did it sometime after 1979.

 

[John S]

The '76 W116 was the first anti-pollution model in Australia having an air pump, soft cams and retarded ignition - but I didn't know that any were fitted with a catalytic converter. The next model, the W126 380 was fitted with a converter, so I suppose the cats were phased in near the end of the W116 production run.

 

[digitalzed]

I think each country moved forward with emission standards at their own pace. I would agree that it very well may have been at the end of the 116's run that it became common place. Also, my car may have had to be retro fitted with a catalytic converter (and the ridiculous looking 5 MPH bumpers) as a California state regulation.

 

[chrisp]

Regarding the mandatory adoption of catalytic converters in the UK I'm pretty sure it was not until 1990. The science behind their use in cold climates like the UK is far from compelling since most research indicated that for the vast majority of typical UK car journeys (e.g. commuting, school run etc.) the cat would not reach operating temperature. At temperatures below optimum operating temperature those cats produced more pollution than a standard exhaust system. This meant that fitting cats to cars would actually increase particulate pollution from vehicles in the majority of cases, or so the argument against their introduction went at the time.

Still, the environmental lobby, abetted by concerned parents, who thought their children might be being brain-damaged by the lead in petrol, got their way and cats + unleaded petrol became compulsory. Shame the benzene in unleaded is definitely carcinogenic to people of all ages.