Droning from my rear end

[Rissy]

Hey all, as the subject name suggests, I've got a drone. It's a persistent noise, but seems to gain in frequency the faster I go, and seems more emphasised when veering to a left direction. If I could put a familiar tag description to it, I would say it sounds like the same sort of vibration rasp you get from a slightly blowing exhaust, except it needs movement from the car to get it.

The noise sounds as though it's coming from the back, more to the left than the right, but with it being more prominent when turning left, I would suspect that it's actually coming from the right, and being transmitted along the frame to confuse me.

Suspicion, obviously, makes me think "bearing" but i'm not sure. This however, I'll admit, could be "normal" since the engine is in the back (I really don't drive the car enough, or have any comparative experience of driving another D' to be able to distinguish normal from abnormal). The new addition to this, is a slight rattle from the back end, which comes as a light metallic noise when crossing over cats eyes on the motorway etc. This one just started on Sunday travelling back down the M1 from Butterley to Rugby on Sunday. Once again, I'm not sure if this has been around for a while or is actually new. The reason i'm saying all this, is that I was, for once, driving without the stereo on at all. Normally I have it on a little, or a lot, depending on my mood. So this time, I was subject to hearing a lot more from the car than normal.

Should I be worried, or not? Any simple checks I can do, which don't involve lifting the car? (I can't jack it up or anything in Rugby!)

How hard is it to replace the rear bearings (presuming you should do BOTH at the same time!?) even if I COULD get the car jacked up?

Any other possibilities for the vibration noise and/or the metallic rattle? (I quickly lay under the car and checked the rear springs, and they seemed fine. At least to the extent of my very quick look at each)

[Rissy]

...Rear wheel bearings.

Is it just one per side, or two (Inner and outer)? From the below, it would suggest only one per side, but quantity is "2", so a little confusing. 2 Per side, or 2 total (1 each side)?

http://store.delorean.com/c-385-4-7-0-drive-axles.aspx

Wheels off, brake callipers off, Wheel nut off centre, remove wheel hub, then expose bearing by releasing it from behind lock ring in groove?

Is that it?

Any other hints or tips?

Time involved?

I'm going to see if I can do the standard checks (hands top and bottom and rock on the wheel to detect any abnormal movement, and spin each wheel and listen for noise) on both side this weekend, IF (big IF) I can successfully get each side jacked up off the ground in turn to do it.....!

Still have the rest of the summer as well as returning the car to Edinburgh to get through (estimated 1000 miles yet!), so need peace of mind.

[Guinney1971]

wheel bearings can rumble for ages, I wouldnt panic tbh - and if rattles and groans
are getting you down, then put the stereo back on - its a 31 year old car, its gonna
moan and whinge from time to time, I just live with it on my car - and I havent got
the luxury of a stereo in mine (yet) to drown them out :lol:

[Rissy]

...ok, update. Tonight, with an array of bricks, planks, and rocking and rolling etc, I've managed to get my dad's jack under each corner and get each wheel off the ground enough to test with the vertical hands push-pull, and also hand spinning tests to listen to the wheel for any weird noises, and feel for any play.

Both rear wheels, solid, no noise, no play, only some light rubbing from the brake pads on the discs (nothing unusual).

Both front wheels, solid, no play, only some light rubbing of the brake pads on the discs, again, nothing unusual. With the front though, when i was spinning the wheels with my hands, if I gently moved the wheel one way, and then the other, just as the wheel changed direction, you could hear a slight "tick" noise, but it would only "tick" once, as the wheel began to move in the opposite direction from the last movement. Again, I didn't think this was anything to worry about.... (I think this might just be the grease snapping inside the lubes parts of the wheel or something.

I'm now thinking it *IS* indeed a blowing gasket or something on the exhaust system, and this is what i'm hearing from behind my head, and maybe the wind is hitting the leak from different angles depending on the direction I have the steering wheel to move the car, or something.

Anyway, until I hear something more drastic, or circumstances change in any way, then I think my confidence has been renewed for the time-being.

I'm due to see stunned_monkey a week on Sunday, so I could hopefully always get him to have a look and listen with me then, see if I can get a second opinion....

[Chris Williams]

Was the 'tick' from the front wheel just on one side? i.e drivers side, was wondering if that could be the angle drive making a noise.
Always difficult to tell where a noise is coming from on a car I have found, sometimes having two people to look and /or drive alongside makes it easier to find.
Chris

[Rissy]

Chris Williams Wrote:Was the 'tick' from the front wheel just on one side? i.e drivers side, was wondering if that could be the angle drive making a noise.
Always difficult to tell where a noise is coming from on a car I have found, sometimes having two people to look and /or drive alongside makes it easier to find.
Chris

This is exactly what I thought, since it was the nearside front I tested first, but the same "tick" noise came from the the offside front too, so that blew that theory out of the water....?!

I had my dad watching in behind each wheel as I tried to wobble it, holding top and bottom, but nothing, not from any wheel!?

[Rich H]

My D used to get a slight 'groaning' type noise when cornering left

I put it down to either a bad CV joint, a rear wheel bearing or the preload on the diff.

I swapped the drive shafts over which eliminated the CV Joints. That left either the bearing or the diff.
Since I wasn't going to waste my time doing the wrong one (which by sod's law would have been the case) I left it alone.

It took five years for the rear wheel bearing to get bad enough for an MOT tester to notice it.

The rear bearing is a one piece unit and you need a mighty big press to get it out.
I can't remember how many tons it took to press it out, but it was lots.

[Rissy]

Just to bring a conclusion to this thread. The droning is coming from my rear nearside wheel bearing. Bought a replacement from stunned_monkey, who just happened to have one at hand at the time of my visit with him. Planning to get this fitted around the time of my next M.O.T.

[Chris Williams]

If you could let us know how you get on fitting this it would be appreciated.
Chris

[Phil Peters]

RichH Wrote:The rear bearing is a one piece unit and you need a mighty big press to get it out.
I can't remember how many tons it took to press it out, but it was lots.

Hi Rich,

Definitely not a home garage job then?

Cheers,

Phil

[Rich H]

You could do it at home, yes, but you'd need a hydraulic press.

I think my bearing was stuck in particularly badly, so I needed something bigger than the average 'Machine Mart' type thing...

[stunned_monkey]

The main challenge is pressing out the old bearing, for which you need something smaller than the outer race but bigger than the inner race, The old bearing can be ground down slightly in about 5 minutes to press in the new one quite nicely.

[Rissy]

I had my old bearing replaced with a new one on Friday. At the same time, it was M.O.T time too. She "failed" again. (Really passed, due to an "understanding" the old guy an I have.)

Once again, offside hand brake. Nothing. Nothing at all. Have looked at it again on the drive yesterday. Had a tweak with the cable, and took the retaining screw with the split pin through it, in another 180 degree turn. Seems better again, but needs a proper test to tell. I've already done these adjustments a year ago, after the last M.O.T, and had no way of a further test, so I don't know if it ever did any good at the time or not, but if it did, then it didn't last at all.
However, the other thing she was supposed to fail on, was my nearside lower ball joint.....again! If you remember, I had the same ball joint replaced in June of 2010. I'm sure there was a thread mention on here at some point. I luckily bought 2 from Ed Uding at the same time, so I'm taking the second, unused one, back along with the car to the garage again on Monday morning, to have the 2 year old one taken out, and the spare put in. 2 years! Unbelievable. Only about 3000 miles! The other side to my knowledge, is coming on 32 years old! Why this failure!? The old guy says it's simple. "They don't make parts like they used to." Is this SO true!? Or is it that Ed is not a good source for the part in question?

I'll be buying ANOTHER spare lower ball joint again before the next MOT, just in case again.

I'm also going to see if the old man can spare 5 mins to put the hand brake to the test again on the rollers. See if my adjustment has done any good at all. It's really the only way to get a feeling for it. I thought about purposely removing a shoe on the good side, basically disabling it, and then test the brake with only the offside potential, but i think that also would lead to a false conclusion, because if the nearside it simply locking on too early, or the offside too late, then this would be hidden by the fact of disabling the nearside altogether. It's a really tedious problem, every year. I'm just lucky the old man is so understanding and lenient with me, he knows i'm trying, and that i'll return as soon as I have the necessary parts to replace those failing i.e. the lower ball joint again. I wonder if i'll be so lucky with a garage when I finally move the old girl down to Rugby when I have a house with a garage....?

On the topic of the bearing. The old one was a right bugger to get out. It came apart into 3 bits trying to remove it, and some of it had welded itself to the spline'd shaft! Getting the new one in was about the same level of difficulty. The guy doing the job said that he'd never had SUCH a tight fit for a bearing before. He did an old Jag a few weeks ago. Almost the identical same set up he said, but much easier to remove and replace the bearing. Although he did also say that the rest of the setup was much worse condition for trying to disassemble due to rust and corrosion. LEX is nice and clean and un-rusted by comparison, so he said that was a nice surprise. I'd like to say I tried out the car properly with the new bearing in place, while driving home, but i didn't. I was too conscious of the lower ball joint wobbling away. So drove home carefully. Monday though, once it's done. I'll have a better go at it, and a better feel. In any way, the droning noise is finally gone now. 8)

I have some pics of the whole operation if anyone is interested. I can get round to putting them up once i'm back in Rugby later in the week.

[stunned_monkey]

viewtopic.php?f=10&t=135
http://www.delorean.ie/forum/viewtopic.php?f=1&t=1259
http://dmctalk.org/showthread.php?4208- ... close-call
http://dmctalk.org/showthread.php?2408- ... -Revisited

In a nutshell, the reproduction joints from DMCH and its dealers were/are flawed and should be avoided.

Quote:The old one was a right bugger to get out. It came apart into 3 bits trying to remove it

That's pretty normal. Getting the bit that ends up welded onto the driveshaft is relatively simple - grind a notch into it and use a hammer and chisel to get it moving. A bit of penetrant and it'll come right off. It's old-school compared to modern cars I'll admit!

[Rissy]

So are we saying, from what I read from your links Martin, that I should buy a pair of lower ball joints from the Eurotech guys then? No cross reference against another car that could be sourced from a motor factors?

(I wish I had known this two years ago when I put up on the forum then, and I'll just be hoping, and sweating tomorrow on the way to the garage that this current one doesn't fail catastrophically! Also with the fact I'm about to replace a known crap failed unit with another known to be crap unit, I'm not happy. This is all needless if people would just come out and share the information in the cross reference area of this club forum, rather than keeping it a secret where it can't help anyone)