Rear Axle Movement

[PeterTR7V8]

I noticed a clunk when torquing up the wheel nuts on the left rear wheel so I looked underneath to see where it came from. I found that when the nut is being leaned on the axel is rotating such that the diff head is moving half an inch upwards.

Later when I was driving the car I found I could replicate the clunk by lifting off/getting on the accelerator.

I assume this is going to be a worn bush on either the traiing arm or tie bar. I'm waiting for some new springs to arrive so will have the rear in bits shortly but is this something someone else has had to deal to?


Never say die. At least not while you're still breathing.

[busheytrader]

Hi Peter,

Hopefully all the metal around your lower suspension mounting points is in good condition. Mine had cracked from the V8's torque and I had to weld in several repair panels to both sides of the floorpan and the rear bulkhead.

The rear end on my 7 had given a huge wiggle accelerating hard up a hill in the dry. Hopefully you just have some worn bushes to replace.

Adam



TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, S/S Single Pipe Exh, 3.08 Rear, 200lb Spax & PolyBushes all round, Anti- Dive, Top Roller Bearings, Capri Vented Discs & Calipers, Braided Hoses, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AT 5 Spokes and Cruise Lights. No Door Stickers. Mine since July 1986, V8 from 1991

[Hasbeen]

Peter, assuming the poor old thing is not coming apart, as mentioned
by Bushy, I think I have the answer.

You are going to find this hard to believe, but it's almost
certain to be the washers on the bolt on the front mount of the
lower control arm, &/or the radius rod.

I chased this clunk for months in the 8. Remember the 8 is an auto,
but even just opening & closing the throttle, at low speeds, in town
would give this clunk. Everything under the back looked, & felt
perfect. Every thing was fully tight, [3 times checked, would you
believe?] Even my guru had no idea. Yes the diff tilts up & down
like that too.

Incidently, this was with the stock diff, before I fitted the strong
one.

Then I noticed a mention, in the 1977 Leyland manual, of the thick
washers on the trailing arm bolts. It was just that, a passing
mention, & nothing else, & not shown in the diagram.

When I checked the washers on the 7, & 8 I did find that those on
the 8 were "normal" thickness washers, for the size, but those on
the 7 were very thick, by comparison.

Swapping the washers from 7 to 8, gave me a silent 8, with a little
clunk from thr 7, no where near as loud as the 8, but still both on,
& off the throttle.

I have full poly bushes every where in the 8, but rubber in the
chassis end of the 7s rear suspension. I THINK THE THICK WASHERS PUT
AN END LOADING ON THE BUSHES BY THE FACE OF THE TRAILING ARMS, where
the thin washers only load the spacer tube, that goes through the
centre of the bush. This must allow some movement, & our clunk.

When I had a good look at the thin washers, they were a little bent,
[concaved], due to the pressure from the nut.

Obviously the factory only used thick washers for a reason. Triumph
was never known for using anything even slightly more expensive,
when avoidable.

Have you done anything recently, at the rear end, & swapped any
washers? Even if not, I'd get some thick washers, [quite thick] or
some off a parts car, [Jolyon has a few doesn't he?] & fit them to
those bolts. It worked for me.

I did a post about this, back then, probably 3 or 4 years ago.

Hasbeen

[PeterTR7V8]

Found that thread thanks http://www.forum.triumphtr7.com/topic.a ... IC_ID=2177 . That's the kind of oddball info that makes the forum invaluable.

I haven't done any work o the rear as far as I recall. I do have some bushes for the lower arms that I bought 2 years ago but never got round to fitting. With the upper tie arms would those bushes be a common enough size or will I need to get them imported?

I'll check those washers next week. The IRL finale & Bathurst has put a dent in my maintenance schedule. I wasnt expecting to hear from you during the big race, Phil. [:)]


Never say die. At least not while you're still breathing.

[Hasbeen]

Peter, I can just see the TV, in another room, when I'm at the
computer. With some things I sort of half watch, then pay attention
after a lot of noise. That way I get to watch the replays.

My racing was before seat belts, sand traps, & safty cars. We kept
on racing, with yellow flag areas, while a truck picked up the
wrecks. We got a white flag to tell us if there was a truck, or
ambulance on the track ahead of us.

Drivers would replace a flat, or a broken wheel, on the side of the
track, & had to do it, with the tool kit supplied with the car.

I do get sick of races which restart every 20 minutes, & will go &
check the computer, when it's too bad.

Thanks for finding that post mate, my old thing times out, looking
for them. I had forgotten setting the thing up with those chocks, to
look listen & feel for that noise. It had driven me mad for months,
before we found it.

Hasbeen

PS. All the Triumph suppliers in Oz stock the poly bushes for 7s.
Some are from other things, & some are EX UK, but held in stock.

H

[john]

Now that has been bugging me for over a year now i have had the same clunk

even checked the passenger seat was bolted down fully

Excellent

[8 whole cylinders worth of punch to ram the world through the windshield and out the rear view mirror. Car & Driver]
1981 Grinnall TR7 v8
1981 Black FHC
1979 & 1980 Black Premium FHC(laid to rest) Sorry


John

[PeterTR7V8]

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by john</i>

Now that has been bugging me for over a year now i have had the same clunk <hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
And here's me thinking it was urgent. [:D][:D]

Here's a tip when it comes to the forum search function. The search process has been told to receive a reply from the computer that stores all our messages within a certain time or assume the search has failed. Because the computer can't always complete the search in the prescribed time it times out. Meanwhile the files have been found & the results are ready but because it too too long the door has been closed. If you hit the back button on your browser & click on Search again the results will come back quicker this time because the work has mostly been done already. I find the 2nd search usually works but sometimes it takes 3 goes.


Never say die. At least not while you're still breathing.

[Hasbeen]

Thanks for the tip, Peter.

John, I hope thick washers work, on your problem. I was getting very
frustrated with it. Made the car feel like some old clunker,
[literally] rather than a loved & pampered lady.

Hasbeen

[Rich in Vancouver]

I have "The Clunk" as well in spite of having a new diff and poly bushes fitted.
And I don't believe that I have any washers on the trailing arms at all! Will check today!
Thanks,
Rich

1975 TR7 ACL764U

[Beans]

Had the same problem, turned out to be one of the upper radius arms.
I usually check all suspension bolts once every one or two years.

Nothing seemed wrong but halfway during a blast through Europe in 2005 I started to notice a clunk, when I had to go of the throttle suddenly. Tightening up the nuts didn’t help so I had to stick with it till we got home.

It turned out that one of the bolts had corroded solid inside the stainless sleeve of the polybush. As a result of this I could only tighten up one side, leaving the bolt’s head with enough play to move under certain load changes.

Hack sawing out the bolt and replacing it with a new one cured the problem.

<center>
<font color="blue"><i>1981 TR7 FHC Sprint (better known as 't Kreng)
1980 TR7 DHC (my first car currently being restored)
In parts a 1980 TR7 PI DHC, 1981 TR7 DHC, 1981 TR7 FHC</font id="blue">
<font color="red">http://tr7beans.blogspot.com/</i></font id="red"></center>

[Hasbeen]

That sounds even harder to find than the wrong washers Beans.

How did you diagnose that, with out tearing the whole thing aapart.

Hasbeen

[PeterTR7V8]

I did the left rear spring today. It was a far easier job than I thought it would be. Undo the bottom shock mount & jack the car up & voila! The springs falls out. Getting the tie arm off was harder. The new spring is Rimmer's 'uprated' part so I hope it can handle the weight of 4 race wheels in & over the boot better than the old ones. Being marginally shorter than the old springs wasn't a good start but at least the new poly insulaters have a bit more meat to them.



Looking at the tie arm I can't see much wrong with them. The rubber bushes look solid, the mount holes were round & the bolts were still shiny. Only the nylocks nuts were a bit weather beaten. These thick washers you speak of Hasbeen. Are they thick as in large diameter AND in actual thickness of the metal? These are the bits that came off. The washers are very normal looking & one was missing from the axle end.



I rang a couple of local places for new bushes. One asked to see the old ones to find a match & the other said 3-4 weeks ex-Australia. Rimmers had my springs here in less than a week! An email from British Auto Care in Brisbane quoted $70 including postage http://bac.com.au/.

I'm missing the bump stops but it doesn't seem to be bumping. I think that's because the tyres are hitting the wheel arches first. [:0]


Never say die. At least not while you're still breathing.

[Reddragon]

Peter

What is the springs rated at that you purchased from Rimmer's? Were you able to buy just the rears or did you have to get a set?

Those yellow pads make the red springs look sharp.

Dale

Dale
1974 TR6
1977 TR7 FHC

[Hasbeen]

Peter, the OD of the washer is as large as the OD of the bush, or
perhaps a little larger.

The thickness is at least twice what you will get as an ordinary
washer for that bolt diameter.

I had to go to a tractor place to get the same OD, & thickness as
was on the 7, which I believe was stock. Probably could have got
them at a big bolt place, in the industrial area of the big smoke,
but who wants to drive in there?

I'll see if I can crawl under one of the things tomorrow & see what
they are, it's a while since I looked at them.

Those in your photo are far too thin, & too small. I can see they
are distorted from the compression you've had on them, even with
these old eyes.

I had the shorter heavier springs made for the 8, & then wasn't game
to fit them at first, as I was frightened they would fall out, if I
got the thing airborne. I could actually fit the springs, with the
shocks in place, just by compressing the things a little, with a
screw driver.

Had to fit an extra rubber, around the shock shaft, inside the
shock, to reduce the length at full extension, before I was game to
use them. They now have a little compression on them, with the
suspension at full droop.

Hasbeen

[Beans]

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Hasbeen</i>

That sounds even harder to find than the wrong washers Beans.
How did you diagnose that, with out tearing the whole thing aapart.<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Got a pretty good indication where to start looking as my navigator could clearly feel it in his buttocks The joys of a solid mounted and pretty firm competition seat [:D]

Found out that the bolt had rusted solid when I had a proper look back home, with the car on axle stands and tried to tighten it up properly. With the nut undone a few turns I couldn’t turn the bolt without turning the stainless sleeve inside the bush.
Took me all of an afternoon to get it out with a hack-saw (and it was an air powered one)

<center>
<font color="blue"><i>1981 TR7 FHC Sprint (better known as 't Kreng)
1980 TR7 DHC (my first car currently being restored)
In parts a 1980 TR7 PI DHC, 1981 TR7 DHC, 1981 TR7 FHC</font id="blue">
<font color="red">http://tr7beans.blogspot.com/</i></font id="red"></center>