Front Wishbone mystery

[ianf]

Dear all,

I was just oiling my trunnions (!) and generally checking the front suspension on my elan with Lotus chassis and standard front wishbones at the weekend when I noticed that the o/s lower wishbone is just about touching the chassis (haven't had the wheel off yet it might actually be making contact) and the bush is protruding at the front of the wishbone. It is as if the wishbone has slid back down the bush to the chassis. Can this happen (pothole or similar) and is it just a case of removing wishbone, pushing the bush back in and reattaching? The front suspension has been rebuilt (not by me) in the last 3,000 miles.

Any help / suggestions welcome.

Many thanks,

Ian

[elansprint71]

Photo?

[Panda]

Hi Ian,
There should be a large flat washer on either side of the bush, in fact either side of all the bushes. This helps to retain the bush if it wears out. don't ask how I know
Alan P

[ianf]

Good morning - it's chilly on the garage floor this morning! Hopefully photo attached, the rubber appears to have come away from the outer bush sleeve (I wasn't sure about that until I took another look), so maybe just a poor bush?

Do you think if I remove the wishbone and replace the bush everything should be back in place. I have yet to remove the wheel to take a look from the side and won't have a chance to do that until the weekend as the Christmas "party" season starts this week.

Very grateful of any thoughts / advice.

Ian

[elangtv2000]

Ian,
That looks like a bushing failure. Replacing them should put things back in position unless there is other damage.
Cheers,
Greg Tatarian
S3, S4

[patrics]

Hi Ian,

I had this happen to mine when I fitted the ?poly? type bush and I don't remember the car even being driven just jacked up a load of times and pushed back and forth in the garage. I think it is bound to happen on any non bonded bush.
I took mine out but Alan?s suggestion of using a large washer inboard as well is a good one ? If I was fitting poly bushes again I would machine the length of the center metal bush and use two washers per arm to restrict the side ways movement as much as possible.

Regards
Steve

[Jeff@Jae]

Strange failure for a rubber/steel bonded bushing. Just replace it and be sure you have the washer and the arm lines up correctly. They usually only do that after 30 years or more !

[miked]

Just a point:
It is worth checking wishbone accuracy (off the car) as I have done this in the past and found them to not be accurate causing side loading. I checked mine against the Lotus drawing and they were out. Having bought these actual ones, I sent them back with all the error info' and got some fresh ones.
I have just noticed the top hat lip coming adrift near the washer on the front NS upper Autobush. It looks like I have something going on. I also noticed that one of my modified roll bar clamps has a floor strike on it (speed bump?) so will be taking this apart to check have I got distortion on this side. I have caught the odd speed bump at very slow speed and figure that this may have pulled the NS bones. I altered my roll bar clamps as they knocked on the chassis cross member. This makes it a tad lower.

I haves spare wishbones so will be checking everything and also doing a dummy build to ensure alignment etc.

Mike

[ianf]

Thanks everyone for your help (and moral support), I won't have time to take it to bits until Christmas but will report back when done. Thanks also for comments about washers and wishbone specification, all will be noted!

Cheers,

Ian

[mariodschy]

Same dilemma I had on mine last week after fitting new polyurethane autobush. I cured it by adding washers also on the inner side where there are normaly no washers located, and also ad washers between damper and wishbone to increase distance to avoide extensive tourque on the innerside of the whisbones.

[Andy8421]

Colin would not be happy.

Probably apocryphal tales, but there are various Chapman quotes and stories about Colin and washers. These range from firing a mechanic for fitting washers to a Lotus 11, to Chapman sitting behind a formula car in the pits removing the washers one by one from under the nuts on the gearbox. The quote apparently attributed to this event was along the lines of 'washers are not getting a free ride on my car'.

There are various other stories about Colin and washers of equally dubious provenance.

[mariodschy]

Colin would not be happy.

I am not happy to with all this washers but it was the only way to cure this problem, i won't drive with whisbones they are only fitted halve. My feeling ist much better to know them fixed without a chance to came off.

[Chancer]

Proper rubber to metral bonded bushes as they used to be made by Silentbloc and Metalistik would not fail in that manner unless very very old, deteriorated and subjected to extreme force, on the test rigs the metal would fail before the rubber to metal bond.

Modern ones? - Well they can fail even Under correct storage conditions before even being fitted to the vehicle.

Are there no flanges on these poly bushes? Do you really need to fit retaining washers other than for peace of mind? That would make for metal to metal contact.

I know that the bushes move relative to the sleeve so there will be wear, something that the rubber to metal bush was invented to overcome but is there no, or so little sideways location that washers and metal to metal contact is needed?

If so I would not want to drive on them, they are a retrograde step.

[mariodschy]

Next time i'll go back to the original bushes.
Modern solutions are not allways the best - lessions lernt!

[peterexpart]

Proper rubber to metral bonded bushes as they used to be made by Silentbloc and Metalistik would not fail in that manner unless very very old, deteriorated and subjected to extreme force, on the test rigs the metal would fail before the rubber to metal bond.

Modern ones? - Well they can fail even Under correct storage conditions before even being fitted to the vehicle.

Are there no flanges on these poly bushes? Do you really need to fit retaining washers other than for peace of mind? That would make for metal to metal contact.

I know that the bushes move relative to the sleeve so there will be wear, something that the rubber to metal bush was invented to overcome but is there no, or so little sideways location that washers and metal to metal contact is needed?

If so I would not want to drive on them, they are a retrograde step.

Also you are instructed in the workshop manual not to tighten the Bolts on these until the car is at the correct ride height, as the Matalastik Bushes give a certain amount of rebound as a torque reaction. You cannot achieve this with the Poly Bushes as they are not held in a fixed position.