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Ragpickers Leggy 986 S.. first real problem: page 9

Unusual problem this weekend. The lower gearbox mount lug pinged off as I was setting off from work. I heard and felt it, thinking it must have been one of the new coil springs cracking. When I checked I found this:

35414710430_f64c3daa77_k.jpg


34993261023_d876e9350b_k.jpg


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What an absolutely terrible design. The thinnest bit of alloy fin is used as the gearbox mount lug!

Anyway, I was puzzled with what to do as a solution. Fortunately a friend gave me the number of a mobile aluminium welder - a rare breed!

34962967734_9771320231_k.jpg


Access isn't as bad as you would think and within an hour he had built the area up with new weld to strengthen it and got it fixed. Hopefully stronger than new!

35803316325_197a323bcb_k.jpg

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Looks like its fixed, tomorrow i'm going to attach it back onto the mount and see. £65 for a job which could have saved me £800 for a second hand box!

Result!

:thumb:
 
The mount on mine snapped as well..Again I heard a ping that sounded like a coil spring snapping!!!
The only clue was the exhaust tail pipe at a weird angle..
Again welded in situ and now all good..
I love my 986..The best Porsche model ever... and I've owned a few
 
I was trailbraking into a left hander 2 days ago when I heard a 'clink' and a thud. As I was late for work I carried on cautiously but noticed that the car was pulling to the left and there was a horrible noise like the front wheel rubbing under heavy braking.

Today is the first time I've been able to get the car on the lift and have a look:

Broken tuning fork:
36293713810_7a4cfee618_k.jpg


Slipped coffin arm bush insert:
36551015351_0804b96281_k.jpg


Drop link broken:
35880103703_099063fa4e_k.jpg


As you can see, there's an awful lot of damage happened due to the failure of the tuning fork. As you can see from the following pictures it is clear that the polybush didn't allow any 'give' next to its anchor point which led to it fatiguing and then failing:
35879585383_8bac12d17b_k.jpg

35854236094_65058abf56_k.jpg

36643027696_00d37de5ef_k.jpg


Without the tuning fork keeping the centre of the wheel pinned in position, under heavy braking the wheel was moving back and rubbing on the leading edge of the front wing. The only think really keeping the hub where it should be was the coffin arm but this was clearly overly stressed in order for the bush insert to move out of the arm.

Needless to say I won't be buying polybushed tuning fork arms again. Good old OE bog standard replacements from now on. I'm obviously going to replace the pair even though only one is damaged along with a new coffin arm.

Could have ended in tears....

:nooo:
 
Top work Raggy, as ever. Especially the suspension refresh though. 8)

What a freak failure on that tuning fork. As Demort says, lucky escape there.
 
Interesting failure. Noted for the future as I will probably rebush my 987 at some point. Will stick with the inner and outer coffin arm bushes I think.
 
All sorted with new tuning fork arms both sides and a new coffin arm on the nearside:

36823311085_95aba83296_k.jpg


It took about 20 minutes to put these back on, its lovely when everything comes off easily, but it wasn't all plain sailing.. First I had to contend with the two 'identical' arms that an eBay seller sent me :roll:

36823542465_02b838f3af_k.jpg


To be fair to them, they sent me a replacement part out by 10am the next day, so it wasn't too bad.

Next episode will be the installation of the new underdrive pulley!

:thumb:
 
I'm interested in the results of the underdrive pulley.
Great work as ever. :thumbs:
 
Today I spent the morning installing the underdrive pulley. This is a first for me as its one of the few mods i've never done.

A forum member (jimk04) has been producing and selling the pulleys. He kindly sourced me the correct belt to go with it. £125 later it arrived and the product looked good.

For those who aren't that familiar with the 986 anatomy, the front of the engine is accessed through a fire wall behind the drivers seat:
36471122140_628c5877b3_k.jpg


Here you can see the two pulleys we are interested in - the large silver pulley at the bottom is the crank pulley which will be replaced, the smaller black one above it is the tensioner pulley which keeps the belt under tension and stops it falling off. Both have a 24mm bolt in them.
36696335232_1ba6ec2309_k.jpg


To remove the crank pulley you can buy the porsche tool which prevents the pulley from rotating when you undo the bolt, or you can place something through one of the holes in the pulley and into the TDC boss to stop it turning. Then with a long 24mm ring spanner, or a shallow 24mm socket you undo the bolt.
36058682503_a6c6df75c4_k.jpg

The original crank pulley, note the notch cut out of the centre hole:
36470797950_7f5a9d31b8_k.jpg


Compared to the new pulley:
36471124480_a5eb239aa1_k.jpg

36696335892_4113b3c5cd_k.jpg


Using a dremel you have to grind down the TDC boss to provide clearance. You can see that the notch on the pulley fits over the notch on the crank pulley mount. This is there to ensure that the pulley turns even if the bolt holding it in is loose, thereby making certain that the ancillaries are powered by the pulley. To this effect, whilst you should make every effort to re-tighten the bolt during re-installation, there is a safety net there.

Here is the amount of TDC boss needed to be removed:
36727386581_7b6db74dee_k.jpg


Pulley offered up:
36470795260_66f3042e99_k.jpg


And re-installed with a bit of loctite on the bolt:
36696708012_c3fa77721d_k.jpg


And thats it! Simply put the new, shorter belt on, fire up the engine to ensure everything is seated properly and then put the fire-wall back. Bobs your uncle, Fanny's your aunt and Robert's your mothers brother!

Has it made any difference?

Well, the most surprising difference initially was how quiet the engine sounds now. Maybe its because its a new belt, maybe because things aren't spinning as quickly, but it is a huge improvement in that regard!

There is no change in how heavy/light the steering feels.

There does appear to be a small but noticeable improvement in punch across the rev range. Certainly not an amazing amount but its there. The bum-dyno says its probably 5-7whp. There was no change in water temp either.

I'm absolutely amazed at the reduction in whirring noise in the cabin though, its worth it for that alone! I think all in all its a good little mod and I would definitely do it again.

:thumb:
 
Could I ask how much clearance you have between the ground down boss and the pulley? - Cheers :thumb:
 
crash7 said:
Could I ask how much clearance you have between the ground down boss and the pulley? - Cheers :thumb:

Hey! I think i was a little too enthusiastic with the dremel and have about 4mm clearance. As there is no back and forth movement of the pulley you could get away with less than 1mm. The hole for the boss seems to be never ending, its very difficult to grind too much off.

:thumb:
 
Little update... The auld girl is on 149k miles now and I did its last service 6102 miles ago which is 1k miles over the interval I like to use.

The weather and salt (especially the salt) has taken its toll on the car this winter with it being used every single day, even in the snow. Actually she performed brilliantly in everything up to 6 inch deep stuff, helped I'm sure by the lack of PSM.

A look around the car revealed the extent of the salty damage:
25973730737_8f0afbcd3c_k.jpg


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A few months ago these were brand new fixings..
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I started off by wire-wheeling the corrosion off the leading edge of the sill and then treating it with Bilt-Hamber Hydrate 80.
25973730517_7ed0406838_k.jpg


Whilst this was curing, and in between applying further coats, I whipped the discs/pads out and changed them..
40845291481_9ce72c2e91_k.jpg


Much better!

Then the oil change, with the mandatory oil-filter check which was as clean as a whistle!
40803661702_f195ad6bb6_k.jpg


Thought I'd take Baz Hart's advice and start using this stuff from now on:
40845292081_577788a553_k.jpg


Along with a funky yellow new oil filter
40845291381_df63b767aa_k.jpg


I then changed the cabin filter and put a new 987 air filter in my 987 airbox before going back to the sill and giving it a quick coat of paint to make it look less like a dogs dinner.
39951236625_e823799e71_k.jpg


So she's had a little bit of a sort ready for the next few months. Once the weather becomes more palatable she'll get some proper attention but at least she's presentable and serviced again.

:thumb:
 

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