I have a 1967 144S in almost perfect shape. It is just back from the paintshop where 4 coats of urethane got on a completly stripped car. Nice.

I had a clunking noise coming from the center of the driving shaft, where the spline from the rear part slips in the front part.

I replaced the 3 universal joints, the center bearing and the rubber holder. When I take off from a standing start, sometimes (1 time on 4) I will get a clunking noise like if someone is hitting the floor with a hammer. The frequence is quite fast and it disappears seconds after appearing. Starting from rest and turning right it will do it almost all the time on startup.

What is happening under my car ? I can't figue out what !

Any help greatly appreciated !

Take care

Ignace

Firstly, GREAT CAR! I kinda wish my wagon were older than '71....but I'll get over it.

One other problem that I wouldn't entirely rule out is clutch chatter.

It wouldn't explain the right turn issue, but it can often feel like the driveshaft.

-Matt B

/// All the posts have good advice but you already know the solution. You said that the noise is when the angle of the shaft changes. The rear bushings are the most likely candidate and the next is the rear springs.

It's not likely that the tremendous power comming from that in line four is wrapping the spring but abuse for years can weaken them. I would go with the suggestion that one or more of the rear bushings is allowing the axle to twist and producing the out of position you are experiencing

Are you sure it is the drive shaft? Could the noise be from the exhaust hitting the car? When you take off you shift the chassis on the suspension and this can cause rubbing, etc.

Hi Tim,

I put my hand between the two front seats when the clunk is there. About where the backrest of the front seats are and also right over the center bearing. The clunk is definitly driving train related.

Also I have to say that the exhaust is new and has the clearance needed.

Thanks for the advice

Ignace

In addition to the other suggestions, have you assessed the condition of the rubber transmission mount. The common upgrade when replacing this mount

is to use a 164 engine mount.It wouldn't hurt to check engine mounts while

doing your investigations....syd

Hi Syd,

Well those 3 supports are about 8 months old (2 engine, one trans.) The transmission one hasn't been upgraded, too bad we didn't know each other a bit earlier !

As For the shock absorber, they are also about 8 months old and I did upgrade the 1/2" lower holding studs with the 5/8" ones.

The rear outer bearings and seals have been replaced too. They are grease type. First time I saw something like this. I have an oil seal closer to the diff. , the bearing and a grease seal. Not much loose there. Don't know about the inner ones though. I did change the oil in the diff. two years ago. 80W90 went in.

Also the rear suspension bushings are one year old (IPD).

The noise seems to appear when the angle of the driving shaft changes.

Have to say I'm really puzzled about this one.

Ignace

The two half shafts also have to be aligned properly. My '74 manual states "The front and rear sections are individually marked with a yellow dot and an arrow. The proppeller shaft must in replaced only as a paired unit and the front and rear sections have to be installed so that the arrows (the dots) point toward each other". The illustration shows the two flanges rotated ninety degrees to each other. Or the two front shaft yokes ninety degrees from the rear shaft yoke.

Hi Dave,

Makes a lot of sense.

Tomorow I'll look for those marks and align them properly.

Tonight, instinctivly I dismanteled the rear driving shaft and plug it in a different place in the middle yoke. Result : the problem is a lot less terrible than it was, the clunk is there one time on 20 instead of one one 4 !

Thanks a lot !

Ignace

Ok, if the first suggestion is no good, are you abslutely sure the sliding yoke on the propshaft is ok. It is unusual for them to get really bad but if they do they can lock and unlock as the transmission winds up. certainly as the car squats down when you accelerate the length of the prop will change, which is why the slider is there.

Also when the UJ's were changed did you check all of them are moving freely? As you put the UJ's in it is possible to get the bearing cap too far in. I usually put each eye of the prop on the workbench and tap the side of the prop with a leather mallet to settle each cap snugly against the circlip.

Are you sure the prop belongs to the car. Volvo subtly changed the flanges and if you have a mismatch the prop will fit but has to be forced with the bolts to lie snugly against the drive flanges on the 'box and axle. Smilarly there has to be free movement on the yoke, ie when the car is at rest the male part of the prop must not be fully home, it should be able to slide both in and out, otherwise he yoke can lock up.

Regards

Hi Pete,

Ok, I think the sliding yoke can be in trouble here. Tonight I rotate the rear half shaft on the center yoke 90 degres. Well the problem is almost gone. I'll look for alignement mark tomorow

As for the u-joint, good advice, but I use the same method as yours to make sure I have no binding there. U joints are OK

Attention will be on the sliding yoke tomorow !

Take care,

Ignace

One further thought, when you rebushed the suspension did you make sure the bolts were tightened up with the car sitting on its wheels. If you tighten with the suspension hanging you get all kinds of weird preloads on the bushes, which can cause judder as thy desperately try to get back to where they are supposed to be.

I like the propshaft out of phase idea, basically all the fixed eyes on the shaft should be in the same plane on both halves of the prop, one half of course is so per definition, he other should echo it. In practise therefore the prop can only be assembled in phase in two ways. Therefore if you have lost the original assembly position it must be one of two ways. In practice I have assembled several props out of diparate halves, with nary a judder yet.

Regards

Check the seals at the rear wheels. They might be oozing lubricant. Perhaps one is leaking and you have a worn bearing. That might account for why the sound is most pronounced when turning in one particular direction. Perhaps there is some lateral slippage when turning because of a worn bearing. Its just another possibility.

Have a look at the rear shockabsorber bushes. As you drive away the axle tries to twist. If those bushes are nadgered it can give the symptom you describe

Regards