suspension bushing Latest

[John_Mc]

suspension bushing up-date

I put new TRF rubber suspension bushings in my front suspension in April. I noticed last night that a couple of the bushings (upper A arms) are already falling apart. Is it expected that some of the rubber compressed by the washer on the fulcrum bracket will shear off (ie it is excess material that is not actually "suspending" the car), or is this a sign of premature failure due to poor quality product, poor quality installation by me, or some other insidious force at work?

 

[TR6oldtimer]

Re: suspension bushing up-date

The rubber bushes act like a torsion bar. That is they flex as the suspension moves up and down. Many people, myself included have installed and tightened them without loading the suspension. So, when the weight of the car and passengers are placed on them, they move farther then designed ripping themselves apart. Instructions state that theses parts should only be tightened with the suspension loaded.

All that said, it might be the quality of the parts.

 

[SCguy]

Re: suspension bushing up-date

My experience with after market "British" rubber is that looks fine when you install it but quickly falls apart. An example is my TR6 which had it's ball joints replaced during it's restoration. By the time my car was finished and ready for the road the rubber boots on the ball joints were already crack. Ted at TSI also has no faith is replacement after market rubber. Whenever possible I've gone with poly on all my cars.

Just my opinion.

 

[Tinster]

Re: suspension bushing up-date

Ray,

I have brand new front suspension in my TR6.
The car broke down after 3 miles of very slow
test rides. Currently broken down.

How do I tighten (or properly tighten) the new
suspension in a loaded condition? Some of it
I was able to tighten with the car on bricks.
But things like the A-Arm bushings? How is it
possible with the wheel in place?

thanks,

dale

 

[prb51]

Re: suspension bushing up-date

Ray,
If you have wire wheels lower the spline (sans wheel of course) on a padded jack stand (carefully).

 

[TR6oldtimer]

Re: suspension bushing up-date

Dale, as prb51 stated, but modified to support and load the suspension by placing it on a padded stand under the lower spring pan then remove the wheel. Do one side at a time.

 

[Tinster]

Re: suspension bushing up-date

Thanks Ray,

Appreciated. A detail question.

I tightening everything according to bentley.

Do I now back off the lock nuts and re-tighten
them under load? Or remove all the new lock nuts
and replace with new while car is sitting on the
spring pan?

In theory- are my lock nuts now over torqued?
or under torqued- with car now sitting on it's
wheels and everything thightened pre-loading?

thanks,

d

 

[TR6oldtimer]

Re: suspension bushing up-date

The object of this procedure is to insure your inner rubber bushes are properly located in the fulcrums prior to tightening. If tightened with the suspension relaxed, they will be outside their range of flex and will eventual tear apart. That said, the only parts to be tightened with the suspension under load are the nuts on the upper fulcrum, and the bolts and nuts on the lower inner fulcrum.

Even after going through all this, if the rubber bushes are of poor quality, they will eventually deteriorate as previously mentioned in this thread and elsewhere.

 

[Moseso]

Re: suspension bushing up-date

I am going to install the polyurethane bushes on my TR3 -- when I get to that point. Do they require the same "tighten under load" treatment?

I too have been puzzled as to just how to get at those nuts under load. I imagined the description given (wheel off -- jack under the spring pan). Thanks for the confirmation.

 

[TR6oldtimer]

Re: suspension bushing up-date

The tighten under load is not needed with polyurethane bushes. Unlike the rubber bushes, they are lubricated and designed to rotate on the fulcrum pin and on the sleeve provided with the lower fulcrum. Check that your upper fulcrum pins are not heavily pitted and can provide a good bearing surface or premature wear can occur.

 

[Tinster]

Re: suspension bushing up-date

That's some real good info Ray!
It really helps us rookies when you experts
share your wisdom.

I guess I lucked out (finally !!) on something
with this bucket of bolts.

Now tell me if I messed up or not? Please?

I completely dismantled the front suspension system,
piece by piece. I stripped the fulcum down to bare metal
and powder coated all but the two pins.

I polished the two pins #800 and finally #1600
and buffed them 000 steel wool.

Here is a photo essay of my fulcrum and poly bushings for the upper A-Arms install.

Will you kindly take a look and tell me if I need to
pull it back out or modify anything? Thanks so much.

https://www.scribd.com/doc/331575/TR6-fulcrum-bushings

dale

 

[RonMacPherson]

Re: suspension bushing up-date

Dale, you used non rubber bushes, didn't you? If so, no problem, just drive it.

 

[TR6oldtimer]

Re: suspension bushing up-date

Dale,

/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif you do not have rubber bushes. You did everything right. Just tighten them down and go.

 

[Moseso]

Re: suspension bushing up-date

Thank you, oldtimer. That's what I thought, but needed some confirmation.

 

[TR3driver]

Re: suspension bushing up-date

I too have been puzzled as to just how to get at those nuts under load.

Another way to accomplish the same thing is to tighten the nuts before you reinstall the spring, with the suspension held at normal ride height. Or, just use the spring compressor to pull the suspension to ride height.

Do the poly upper bushings not come with sleeves then ? I used Nylatron, and they definitely came with sleeves to slide over the old pin, to give a nice clean (and hard) bearing surface for the Nylatron to work against.

 

[TR6oldtimer]

Re: suspension bushing up-date

My lower poly bushings from TRF had sleeves, but not the upper. Should have gone with the more expensive set.

 

[TR3driver]

Re: suspension bushing up-date

Thanks, Ray.