Sunday 1 September 2013

Bad day at the office...

A few weeks ago the Spitfire's front suspension started to creak and groan a bit. I had a poke about last weekend and spotted that the lower shock bushes were looking badly deformed. For some reason that I can't remember now I'd left the original rubber bushes in the Koni's when I was building up the rolling chassis back in in 2001 - I'd used Superflex almost everywhere else - so I wasn't that surprised that they had eventually expired.

I got Superflex bushes for the shocks and also the front trunnions (which were the only other standard bushes left in during the chassis rebuild) during the week and set to work on Saturday morning expecting the job to be finished later that day. At the same time I was hoping to fit the progressive front springs that I've had lying around for a year and a half.

I suppose the first sign that things weren't going to go the way I'd planned was when I came to loosen the O/S front trunnion bolt. The bolt and nut were way off centre in the lower wishbone - so much so that I couldn't get a ring spanner on the head of the bolt or the nut. Alarm bells started ringing and my suspicions were proved right once I got the trunnion bolt out - the holes in the lower wishbone were badly ovaled.



Things went from bad to worse very quickly. The O/S lower shock bolt then turned out to be seized. And it wasn't for budging, in spite of some aggressive "therapy". Plan B was then put into action - remove the lower wishbone with the shock still attached and sort it on the bench. Plan B progressed as far as finding out that the rear lower wishbone bolt was also seized.

At this point I had to walk away for a while. When I came back a bit later I decided to tackle the nearside - with virtually the same results. The trunnion bolt and nut on this side of the car were also way off centre in the lower wishbone. I thought things were looking up when the N/S shock bolt came out easily but it was a false dawn - the trunnion bolt on this side of car turned out to be seized. And just like the offside the rear lower wishbone bolt on this side also turned out to be seized when I tried to put Plan B into action for the second time.

At this point I lost the plot somewhat, gave up all thought of repairing the ovaled holes in the lower wishbones and got the angle grinder out. The wishbones and shocks were off the car in pretty short order thereafter!

If anything, the N/S lower wishbone was more ovaled than the O/S.


My theory that the lower shock absorber bushes were the source of the creaking and groaning proved to be correct. They were in a dreadful state.


In fact much of what I took off the Spitfire yesterday and today wasn't in very good condition. A bit disappointing really - I know that the stuff has been on the car for over ten years but since it was put back on the road in 2003 it's only done 25k miles and in that time it's been well looked after and it's never been used during the winter.

The badly corroded O/S trunnion bush sleeve gives a good idea of what most of it was like.


The only things in there that I found in good condition are the Superflex bushes (fitted to the top and bottom wishbones and anti-roll bar) and - thankfully - the trunnions and vertical links. There's no detectable play whatsoever in the trunnions and they turn very smoothly on the vertical links.

The lower wishbones were original so they date back to 1978 and don't owe me anything - but they were perfectly OK when I rebuilt the chassis and it's a bit worrying that they ovaled to the extent they did in space of 25k miles. I wonder if the heavier engine (2.5 vs 1500) and wide tyres (185/60-13s) I was running until last year had a part to play in it?

I also need to have a good look the O/S rear lower wishbone mounting bracket. It looks like the seized bolt and sleeve have been turning in the bracket and it appears that this has resulted in wear to the inner face of the mounting bracket. I can feel a step and the hole looks slightly ovaled. If I need to change this then it's going to be a real PITA - I can't get at the nut on the inner chassis rail from below because of the exhaust manifold downpipes and I can't get at it from above because of the starter motor.

The N/S rear lower wishbone mounting bracket in which the bolt and sleeve were also seized is OK.

So what I thought was going to be a quick and inexpensive repair has turned into a bit of an expensive marathon. In addition to the extra bits required - O/S and N/S lower wishbones, 1 x rear lower wishbone mounting bracket (possibly), some replacement Superflex bushes (for the ones that got cut off) and some other miscellaneous bits and pieces there's no way I can put the shocks and anti-roll bar back on the car without cleaning them up and painting them.

I think the moral of the story is not to leave the suspension unmolested for so long. In future I'll be stripping it down every three or four years while the Spitfire is laid up over the winter. And I'll be doing the rear suspension when the Spitfire is garaged this winter.

The Saloon didn't get ignored this weekend - in between all of the above I've managed to get the protective top coat on the front. Just got to finish the same process on the rear lamp panel and that'll be the niff naff and trivia finished and the real work will start in earnest!


2 comments:

  1. Hi Bill - just reading your blog, and I MAY have some of the parts that you need for your Spit, if you haven't already purchased them - I have many sets of wishbones in the garage, and would rather see them go to a good home than scrap them - let me know if you're interested and I'll take a look. PM me on the clubtriumph site (username npanne).

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  2. Thanks for the message - I'd already ordered a pair of new wishbones from Canley Classics. Will contact you via the forum cause I'd quite like an extra pair to keep as spares.

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