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#1 oldtuckunder

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Posted 27 July 2017 - 05:03 PM

Ok guys looks for some input to decide if I can run Car at Castle Combe this weekend.

 

On way back from event at Shelsly at the weekend noticed a slight clunk, clunk from rear when trundling along, and thought bugger that a UJ starting to go. Couldn't decide which side, but thought maybe left, but its hard to tell as it could just be sound bouncing around behind the seats.

 

Too it out for a very short run Tuesday evening for a pint and to meet Roger and pick up drive shaft after its trip to Spain and return.  Knocking now quite pronounced at above 20 mph and in a straight line, no apparent difference when cornering in either direction. Yesterday jacked it up and looked at UJ's I always paint the end of the cups and circlips when fitting new UJ's as it makes it easy to spot if a cup is tracking, 2 showing signs of tracking on RH all LH looked good, so took a gamble and removed, stripped and replaced RH UJ, and think I have about the right pre-load on the cups by planning with different circlips. Test drive today, Noise still there just the same, so that was a waste of 4 hours.

 

So now conundrum, as I only have limited time tomorrow before deciding if I compete at CC this weekend

 

Do I gamble that changing the LH might cure it, or am I listening to a diff noise?

 

Don't think its propshaft, certainly not front UJ, no sign of tracking on rear propshaft UJ and both were replaced when the propshaft was balanced last year.

 

If I think its diff then I may just run with it on Saturday and if it goes bang it goes bang, and I have one that I'm in the middle of rebuilding that I could finish and fit for Loton Park next weekend. If its LH UJ then no will I run without replacing, but don't really wan't to pull it half apart to change UJ and then find I have to repeat to change the diff.

 

I have sheared drive shaft pinions before, and blown diff's up completely on Autotests, but never had a diff go a bit bad so not sure what noise it might make?

 

Any input gratefully received

 

OH PS this in non rotoflex

 

Alan 



#2 Nick Jones

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Posted 27 July 2017 - 05:35 PM

Was going to say UJ cup pre-load - but you seem to have that covered.  Could still be the other side.

 

I've had sick diffs make odd clunking noises before when the cross pin was about done, but only when cornering and I'm guessing this is probably LSD anyway?

 

Does the noise vary dependent on power on/coasting/over-run?  Would expect a missing tooth to make different noises dependent on load.  If you have a drain plug you could try dropping the oil and see what falls out?

 

Does braking have any effect?

 

Hub nuts still tight? Wheel nuts tight (incl. front)?  (Sorry, but I know what I'm capable of.....)

 

Propshaft bolts tight?

 

Nick



#3 oldtuckunder

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Posted 27 July 2017 - 06:02 PM

All good inputs!

 

Checked wheel nuts, just had both rears off, so double checked

Will check prop shaft bolts

Noise seems fairly consistent above 15-20 mph under drive or over run

Have Drain Plug will check oil, but with plate LSD it's never nice :-)

Found this video of similar noise at about 25 secs in, rest of time too much surround noise 



#4 Nick Jones

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Posted 27 July 2017 - 08:57 PM

Sorry for slow response - just nipped out to mow the lawn and half the churchyard (don't ask!).  There's a lot of it and it was very long......

 

hmm...... to me that sounds like propshaft speed rather than driveshaft speed........ maybe.  Pinion tooth?  Could still be a driveshaft UJ though as they tend to make double rotational speed noises when one axis fails.  Take it you've had a good lever at the remaining suspect with a chunky screwdriver?

 

Can you pop it up on stands with wheels and brake drums off and run it in top gear.  This tends to make rattles and rumbles worse as nothing is torque loaded and you can crawl under for a closer look/listen - with great caution obviously.

 

Good luck in your search!

 

Nick



#5 oldtuckunder

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Posted 27 July 2017 - 10:48 PM

Ok checked rear prop shaft UJ feels solid as a rock

Checked Hub nuts, all good,

Drained diff, nothing but the normal fining's from plate LSD

Spent an hour on my back rotating everything, and concluding nothing.

So whilst up on stands (unfortunately not with wheels & drums off and only in third gear) had it running at about 1000 rpm which I recon ought to be about 15 mph when the noise was very audible, but not much noise? a vauge hint, but almost a cycle like 10-20 secs normal then almost a shudder and groan then 10-20 secs normal then another shudder, almost thought I could detect a slight rumble from front prop area, but not sure.

 

So with suspension dropped as far as it will go with anti camber kit, and no load on wheels, fairly quiet, so suspecting UJ when drive shaft angles are different, (or of course could be diff when there is real load). So decide to investigate LH UJ, no apparent play be levering but couldn't rule out a tad, so set about removing circlips, gently tapping cups in and fitting thicker circlips, managed on three, fourth said no way thicker. Ran out of time to test so will see in the morning, will also try powered test in the air with wheels and drums off just in case it highlights something.

 

Alan 



#6 oldtuckunder

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Posted 28 July 2017 - 10:51 AM

OK could this be the problem, taking Nicks advice ran it in 4th on stands with wheels and hubs off, took a couple of videos, first is LH rear back plate firm and steady, second two are RH back plate wobbling around a bit?  so could be RH bearings going?  No clunk clunk noise but no load? About to put hubs wheels back on and test drive after re loading UJ's last night with different circlips, in situe!

 

Alan

 

https://www.youtube....h?v=fRS3pO9N3ow

 

https://www.youtube....h?v=BEDtDqPYsHk

 

https://www.youtube....h?v=ISMybvUw-zw



#7 oldtuckunder

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Posted 28 July 2017 - 11:55 AM

Just been for test drive with another pair of ears on board and both convinced that noise is from LH side, so may just be UJ on that side, appeared a bit quieter than yesterday so maybe playing with circlips did something. So anyway nothing for it complete strip and inspection and sort it!"

 

Alan



#8 Nick Jones

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Posted 28 July 2017 - 12:37 PM

Backplate movement like that usually means the driveshaft is bent - which is very common.  I don't think a little bit matters much except that it shows it's taken a hit at some point.  After I rolled my Herald, one driveshaft was bent enough to make the car yaw as it drove......  The marshalls did that turning it the right way up, along with 60% of the total body damage.

 

Nick



#9 rogerguzzi

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Posted 28 July 2017 - 12:45 PM

Hello All

              I know nothing really but I would say the halfshaft is bent and the bearings are starting to fail?

 

I can't see how the back plate would wobble with a loose U/J!

 

My U/J made the familiar clicking noise but the wheel bearings (in SPAIN!!!!!) made a Grunching noise that gradually got to a bucket of stones!

 

Still as I say I know nothing I am from Barcelona!

 

Roger



#10 rogerguzzi

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Posted 28 July 2017 - 12:47 PM

Backplate movement like that usually means the driveshaft is bent - which is very common.  I don't think a little bit matters much except that it shows it's taken a hit at some point.  After I rolled my Herald, one driveshaft was bent enough to make the car yaw as it drove......  The marshalls did that turning it the right way up, along with 60% of the total body damage.

 

Nick

Hello Nick

                Beat me to it?

 

Roger



#11 oldtuckunder

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Posted 29 July 2017 - 05:49 PM

FOUND IT!

 

 

Looks like I have contracted Roger's disease!  LH Wheel bearing shot and rumbly!, funny that it sounded like a UJ clunking though.

 

Shame I opted that the noise was coming from RH and did that UJ, rather than the LH as it was obvious as soon as I had the assembly off that it was the bearing, but as I didn't have any bearings I still wouldn't have sorted in time for CC. Also funny that running with hubs off yesterday there wasn't the faintest noise coming from it!

 

I haven't stripped it yet as I need to find a Puller, Roger?

 

Have both sides stripped off, so had a good a feel of the RH one and can detect a tiny amount of play, so may play safe and change both as they were both changed at the same time about 2 years ago.

 

Anyway progress, actual problem found so not going to be changing things just in case.

 

Alan



#12 rogerguzzi

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Posted 29 July 2017 - 11:03 PM

Hello Alan

               You are welcome to borrow my bit of kit or bring the 2 drive shafts up to me and we can both fight them(possibly with the oxy/acetalene heat?)

 

Give me a ring or pm me

 

Roger

 

ps have you got a new (straight)drive shaft?



#13 oldtuckunder

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Posted 01 August 2017 - 07:32 PM

How to pick best two of three driveshafts

 

After aborted attempt using big press yesterday, which resulted in damage to a hub on spare assembly I had, I gave up and ordered the proper hub puller, which arrived today and worked a treat on both sides. Only reason I bought one on next day delivery was that I had the back up of heading up to Rogers if it didn't turn up, or didn't work!

 

Anyway my conundrum, and I need to decide what I do this evening as I really need to get this all back together tomorrow, if I stand a hope of testing before Loton Park on Saturday.

 

OH yes Main Bearing shot, rumbly and stiff on LH, but no damage to hub of shaft at that bearing, guess I caught it quick enough.

 

I have three drive shafts.

 

1) A spare that if I spin it in the lathe appears to be straight, and has good bearing surfaces, and good UJ yokes.

2) The current RH one that as we saw has a slight wobble (hardly detectable in the lathe) has good bearing surfaces, but the UJ Yokes are about at their limit 

3) The current LH one that appears straight, has good UJ Yokes, the bearing surface where the main bearing sits is good (and the bearing was a good tight fit on the shaft) however there is some radial ridging right where the roller bearing sits.

 

So do I replace the RH one with the good spare and solve the wobble and sloppy Yokes and see if I can polish up the roller bearing surface on the LH one,  or do I replace the LH one and live with the slight wobble on the right and know that before long the UJ will start playing up, but hopefully not before the end of the season.

 

Votes and reasons folks?

 

Alan



#14 oldtuckunder

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Posted 01 August 2017 - 07:55 PM

OK answered my own question, just put the LH one in the lathe and the radial scores just disappeared with very fine emery, one left but from measuring is where the outer cage of the roller sits so should be fine.

 

So I think that's the choice made just have to paint and reassemble fast!

 

Alan 



#15 oldtuckunder

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Posted 04 August 2017 - 07:15 PM

4 DAYS FROM HELL since last posting!

 

Cracked Hub Casting, Split Yoke, Out of spec GKN UJ's, Paint that wouldn't dry! Saved by arrival of good LR UJ's yesterday, finally all back together this afternoon and test drive an hour ago, so we go to Loton Park!  Was getting desperate yesterday afternoon but discovered that Championship day is Sunday 6th not Saturday 5th, so found I had an extra day to get it right which took pressure of a bit. All I have to do is sort 5mm spacers for the front wheels as just discovered that the newly refurbished 13" steel wheels (with SN835's for the rain) just foul the calipers! and machine the heads off the wheel nuts as they don't have the depth for the long studs when using steel rims!

 

Full story if we make it back from Loton, going to be the longest single drive the Vitesse has had on the roads for about 30 years!

 

Alan 



#16 Nick Jones

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Posted 04 August 2017 - 07:35 PM

Good luck for Loton then - and the drive home.

 

Not had out of spec actual UJs but one of the propshaft UJ flanges on my PI had the bolt PCD centre offset by about 2mm from the centralising spigot so if you got it central you couldn't get the bolts in and if you'd got the bolts in it wasn't central and vibrated badly.  That went in the bin......

 

Nick



#17 oldtuckunder

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Posted 07 August 2017 - 03:26 PM

Well finally back end all back together late Friday and a quick test drive revealed a quiet rear, in fact quieter than I recall for a while, so apart from the failing bearing there had been a bit of other slack and wear building up over the last season.

 

Saturday sorted out spacers and wheel nuts (well juggled a few things and found some big washers) so got new steel wheels and the Falken SN832's fitted. Took the decision that as the forecast was a bit iffy for Sunday and as that the car was going to be driven there!,  I'd opt for the the larger diameter new rain tyres (has to be driven on same tyres as will compete in, so no changing) and help keep the revs down a bit on the way (currently 4K = 60mph). Very short test run on the SN832's but only far enough to ascertain that they appeared round and didn't go flat :-) and thought the 70 odd mile trip to Loton should scrub them in nicely. Nick had given me the pressures he runs them at on his Vitesse, so in the absence of any testing time thought what's good for the goose is good for the gander.

 

Stayed dry all day Sunday so rain gamble didn't pay off!  But was an interesting experiment! further compounded by the fact that they completely resurfaced Loton Park in early July so its brand new tarmac!  I usually run either 13" Alloys with 185/60's or 15" Alloys with 185-195/55's with very square shouldered profiles, and am sort of used to driving on rails in the dry, the T1R's just hang on and hang on before twitching but I can usually feel it about to happen.  The SN832's apart from being a 70 profile have very rounded shoulders, and very flexible sidewall's (If you push on the side of the car whilst static the cars will move side to side just on the flex in the sidewalls!)

 

So some of this is subjective as I have no idea what the T1R's would have been like on the new tarmac, but first practice run (so not trying too hard), after the first couple of corners I backed off a bit as I scared myself as the car squirmed all over the track! and as I drove back down with a time about 3 secs off my normal thought "this was a mistake".  Second practice run thought can't change the tyres, so have to change the driving style and see how I get on! Still scary but starting to get a feel for when/what was happening and managed to squeeze just over 2 secs off first practice.

 

Deep thoughts over lunch, do I try playing with tyre pressures? maybe pump them up hard enough that it reduces the flex?  but then how will they react (and assuming that Nick didn't feel he was dicing with death with the tyres at that pressure and I had liked the feel of Nick's at CC) maybe they are OK, just totally different. So though leave well alone and just try driving to them!

 

First timed run after lunch, again scary in I'm having fun way, and went for it, didn't come off (although I had front and rear wheel drift experiences that I'm not used to) and started to get a feel for how predictive and progressive the drift was (would love some video footage of what the tyre walls were doing on some hard corners).  Wow another 1.5 secs quicker and 0.12 secs quicker than my previous PB at Loton. Well that was smile generating, maybe I am starting to like these tyres!

 

Final timed run!  OK my ambition for Loton had been to hit my Bogey/Target time 72.50 secs (they are supposed to be impossible to anyone but the Stig on a good day), but had all but given up on that after first practice runs. OK lets just go for it! if something breaks (i.e me!) then we brought the trailer with the TR8 on so have recovery options!  More slip sliding away and fast heart rate at end (bugger missed the timing display) what was the time?  Had to wait till return to paddock to discover a 72.58, just 0.08 off my bogey!   Not confirmed yet (as the handicap results take a day or two to emerge) but I think good enough for 3rd out of 10 in the Triumph class. Another 0.9 sec quicker and we could have won, and I think the tyres had it in them as we were getting markedly quicker every run.

 

Anyway fun day, almost like learning to drive a different car!

 

So for cheap budget tyres I'm pleased, for damp+ days (which is what I got them for) I will certainly use, just have to decide on dry days if I persevere with the different handling or revert to lower/sharper profiles!  Would love to get someone to test the rubber hardness on the SN832's as I actually think they are quite soft, the tread was actually showing that it had been worked and got warm by the end of the day, especially on the fronts!

 

Didn't quite get around to the trials and tribulations of rebuilding the back end, but hopefully will find 10 mins or so this week for an update.

 

Alan 



#18 Nick Jones

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Posted 07 August 2017 - 04:41 PM

SN832s are soft.  Good for lightish cars and good in the wet.  I think mine would have got fairly shredded at CC if it had been dry!  Did 100 miles on the track that day.

 

Can't really comment on the differences compared to stiffer, squarer or lower profile tyres because I've always run tall squashy tyres on my small chassis cars.  I'd rather they drift predictably that let go suddenly.  Your times suggest something was working for you too!  They should improve more as they wear (in the dry) as the tread squirm reduces - maybe.

 

I'd intended to try different tyre pressures at CC but as it was so flippin' wet and we seemed to have as much grip as anyone I decided not to mess!  Quite likely some advantage to be gained.

 

Nick






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