Vibration

Hi

I've just finished replacing the chassis on my series 3 SWB I've also fitted parabolic springs. It now has a bad vibration that didn't used to be there before I changed the chassis and springs.

The vibration only occurs at around 30 - 40 mph and 65 - 70 mph, it is worse when accelerating and decelerating through these speeds.

I originally thought it was the prop shaft as it was worn and rattling all over the place so I fitted a new shaft, but it made no difference.

The only difference I can see from before I changed the chassis and springs is the springs have lifted it a good couple of inches, can this make a difference?

Anyone got any ideas on what it may be?

Thanks

Liam

formatting link

Reply to
Liam
Loading thread data ...

My first thought would have been a loose propshaft, or a badly worn one. You've already seen to that one. Do you have FWH on the front? If not it'd be worth checking the front one too, though as it's worse on accel/decel this isn't likely.

The propshaft UJs can only cope with a limited range of angles from the g-box to the back axle. Your setup sounds like it may have exceeded this which may explain the problem. If you've got a lot of extra lift over the standard setup (ie more than 1in) you may start to get problems. There is a prop available with a double hardy-splicer on, which can cope with more extreme angles.

Another thing to check is the pinion on the rear diff. There's a castalleted nut / split pin that may have come loose allowing some play on the splined shaft, or it may have been over tightened causing some binding. More likeley to be looseneess causing the problem.

All the best Andy

Reply to
Andy Warner

On or around Thu, 15 Apr 2004 23:49:51 +0100, "Andy Warner" enlightened us thusly:

Assuming the problem has only arrived with the new springs as you say, it sounds like propshaft angle, one end or the other.

You can also get some special wedges to put under the springs to tilt the axle slightly. Chris Perfect use to sell 'em, I assume he still does.

formatting link

Reply to
Austin Shackles

There's a slight trade-off here. It reduces the UJ angles, but introduces a slight speed variation because the input and output are no longer parallel.

Reply to
David G. Bell

snip

snip

Liam

Congratulations, you now have a mini 101! This sounds like the dreaded propshaft rumble that afflicts these mighty machines, typically it is the front one that is worse. I have also experienced it on a Range Rover with a knackered spline on the front prop. You only mention changing one prop, have you had a look at the other one? There was a site advertising uprated props in one of the land rover mags, but can't put my hands on the copy at the moment.

HTH

Mike

Reply to
Mike Derrick

Cough, splutter...

Unexpected ambush, you Derrick, are a cad...

Reply to
Mother

I have FWH which I usually have unlocked, I've just tried them locked and the vibration gets much worse, although this is partly due to with the poor condition of the front prop, but definitely worse than it used to be. Some one mentioned to me that you can get a prop with twin UJs on each end, anyone know who sells them and will they make a difference?

Thanks

Liam

formatting link

Reply to
Liam

I had that off a few months ago to replace the oil seal. Just had a check and is OK.

Thanks

Liam

formatting link

Reply to
Liam

On or around Fri, 16 Apr 2004 13:30:20 +0100 (BST), snipped-for-privacy@zhochaka.demon.co.uk ("David G. Bell") enlightened us thusly:

depends on what's causing the vibes, I suppose.

Reply to
Austin Shackles

When I fitted parabolics to my previous Series IIa SWB I experienced an appalling vibration above 25mph. I also made the initial assumption that it was the propshaft. It turned out that it was a loose nut that holds the drive flange onto the back of the transfer box which was allowing the handbrake drum and front of the rear propshaft to move about like crazy. Tightened it up and the vibration reduced massively, then replaced the propshaft as the splines were rather worn and the vibration disappeared completely.

Reply to
Phil Gardiner

Phil Gardiner wrote in news:c5pm3d$4h7ms$ snipped-for-privacy@ID-160147.news.uni-berlin.de:

There's an article on this in Land Rover Owner International June 2001. Maybe LRO's back numbers department can help you?

Or if you care to send me your fax number, I will fax the article to you.

Also, try

formatting link
Derry

Reply to
Derry Argue

Don't have a fax, could you may be email a copy of the article?

Thanks

Liam

Reply to
Liam

"Liam" wrote in news:0ifgc.5320$ snipped-for-privacy@news-binary.blueyonder.co.uk:

Erm..that sounds technical and I don't do technical..but I'll try anyway.

Derry

Reply to
Derry Argue

There was a post ages ago with a link to a site. As they allow the prop to work at a steeper angle, yes they will make a big difference. I'll see if I can find the site

Andy

Reply to
Andy Warner

Here's how to make one:

formatting link

Reply to
Andy Warner

That's a good pictorial guide Mr. Austin has put together, if I weren't so hamfisted I'd consider having a bash, based on this site.

AJH

Reply to
sylva

On or around Sun, 18 Apr 2004 12:38:43 +0100, "Andy Warner" enlightened us thusly:

Scorpion Racing, I think, sell 'em. but it'd try to establish if this is indeed your problem first - unless you've specifically gone for lifted springs, parabolics shouldn't be that much taller than OE springs, they seem taller as the old ones have invariably sagged.

Reply to
Austin Shackles

On or around Sun, 18 Apr 2004 12:42:25 +0100, "Andy Warner" enlightened us thusly:

pity he calls it a CV joint throughout. If it *was* a CV joint I doubt it'd have problems. In fact, has anyone tried that approach?

note that on front shafts, on LRs, they're assembled deliberately out of phase, by a different angle on the series when compared with the

90/110/RR/Disco (which I *think* all use the same front shaft, except for cat-euipped V8s, whicha have a solid front shaft which gives more clearance for the exhaust, or something).

I daresay this still applies if you fit a double joint.

Reply to
Austin Shackles

Good point. Why not load up with a few people in the back and see if the vibration's still there with a better rear axle to chassis height. Suspension will sit down nicely with a decent weight in the back and should allow you to work out better what the problem is.

Andy

Reply to
Andy Warner

Good idea I think I'll go down to my mates farm sometime this week there's sure to be something heavy enough there.

I've just measured the distance between the axles and the chassis the front is 5.5 inch and the rear 7.5 inch. The Haynes says the front should be 4.41 inch and rear 5.67 inch. That's just over 1 inch lift on the front and 1.83 inch at the rear. Is this enough to cause the problem?

I've also worked out that the prop shaft is sitting down at an angle of aprox. 9.85 degrees. What is the max angle that the UJ work at?

Thanks

Liam

Reply to
Liam

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.