The Manhattan Project

Ongoing and archived Porsche (and other marques) restoration threads from DDK members

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AndrewSlater
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Re: The Manhattan Project

Post by AndrewSlater »

sladey wrote:That’s why I like Centre Gravity. He won’t leave it until he has got it perfect.
Yes I've heard good things about CG - in my case I thought I would use a more local specialist. Maybe I should have set my sights further.

My specialist suggested that the settings might just be out because I'd forgotten to tighten some of the suspension fixings.
Keen to prove that wrong I asked to have a look under the car whilst it was on the ramps.
As expected no sign of any loose bolts or fixings - however I did spot that a patch of paint was peeling off underneath the pedal box.
Now personally I would have mentioned noticing that on a freshly restored car - lucky I asked to look myself.

So clearly I had a brake fluid leak and a portion of the paintwork the size of your hand was loose under the car - great - oh well lucky I spotted it.

I got the car home and stripped out the pedal box - yet loose paint also under the pedal box on the inside of the car. Now the pedal box had been fully restored during the original restoration but was now looking much worse for wear.

Suspecting a master cylinder leak I ordered a new one from Heritage parts, and started to strip the pedal box down to repaint it and get it back to fresh.

Reinspecting the footwell area it was obvious that brake fluid was getting into the footwell, lifting the paint and then dribbling through the jigging point under the pedal box and through to the underside where it lifted more paint.

I had assumed it was leaking from the master cylinder shaft but there was no paint lift on the face that secures the master cylinder.
After much detective work it turned out to be leaking from the brake reservoir / flexible pipe union and following down the plastic piping until it eventually dripped into the footwell. It must have been a very small leak but one that had probably taken many many months to materialise.

When I had fit the plastic pipes from the master cylinder to the brake reservoir I had never been confident as to which pipe went where. I'd tried both options and neither seemed ideal. I always felt that the pipes strained on the rubber grommets as they left the master cylinder.

I waited for the new master cylinder to arrive ( although there was nothing wrong with the old one ) and then spent many hours trial fitting the pipes in different orientations. I finally got a fit that seemed much better than my first attempt.

Now to solve the main problem of the leak. So it turns out that the flexible brake piping I had used had a fractionally large inner diameter such that even with the hose clamps fully tightened there was a very slight weep.

New piping fitted and it was all snug and tight.

Annoyingly in diassembling my pedal box I broke one of the bronze bushings - so I had to order a new bushing kit again - more delays!

The next step was to repaint the pedal box area. The interior was an easy clean up and satin black. The exterior required reapplying body sealer around the pedal box plate, new textured underseal, followed by three coats of signal orange and a clear wax to match the previous state of the underside.

Having placed the car back on axle stands to rebleed all the brake systems again, I took the decision to change the brake pads over.
I'd originally gone for Borg and Beck standard pads, but always thought the braking could be better.

Now I've tried EBC greenstuff on the 912 and at best they are slightly better than stock pads.
This time I thought I would try the more costly redstuff pads

Image

Of course I used the selection guide that incorrectly shows the incorrect large pads for the fronts.
My 2.7 has the same small pads front and rear - oh well it's only money :) More pads ordered.

The final funny thing was that when fitting the nsr brake pads I spotted something that didn't quite look right.
That's right the alignment specialist had left one of his tools wedged in a spot in my back suspension ( might explain the new clonking sound! )

So hopefully the leak is fixed, the pedal box refurbished and maybe the brakes are slightly upgraded - time will tell.
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
jtparr
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Re: The Manhattan Project

Post by jtparr »

Blimey....got there in the end.... :)
1974 2.7 Carrera
(full restoration. now as an RS Touring)
1963 3.8 E Type
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911hillclimber
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Re: The Manhattan Project

Post by 911hillclimber »

What a right game you seem to have at every turn!
Perseverance pays off always, keep at it.

As to pads, bit like 'what is the best oil?' but over the 30 years with mine I've tried a few inc the Green Stuff EBC which seemed worse than the stock pads to me.

Aren't red one for track days?

Anyway, the Carbone Lorraine pads are 'reassuringly expensive' and a bit noisy, but sure do stop the car.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
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AndrewSlater
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Re: The Manhattan Project

Post by AndrewSlater »

911hillclimber wrote:What a right game you seem to have at every turn!
Perseverance pays off always, keep at it.
Yes another distraction, but when it comes to brakes it was worth the effort getting down to the root of the problem, which was a very subtle weep, easy to miss the first time and didn't the braking.

Oh well at least I have a new shiny master cylinder and a shiny pedal box again - the old ones were a bit dusty anyway :lol:

I've put it behind me, now just need a dry day to take the car out for another shakedown.
The EBC redstuff pads are for track / fast street use ( that seems to fit my street driving style )
They seemed cheap compared with the pads on my Cayman which have another nought on the end, although less cheap when you buy the wrong ones.

Maybe try the Carbone Lorraine ones next time.
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
gtBen
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Re: The Manhattan Project

Post by gtBen »

How's it going here :angel4:
911 -74, 924S -86, a111 -55, @lagteknik
Ian Donkin
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Re: The Manhattan Project

Post by Ian Donkin »

Brilliant thread and an awesome primer for some of the future joys that await me...

The only thing in the whole thread that made me wince (apart from your misfortunes), was the Blockley tyres - have you driven the car spiritedly in wet conditions since you got it back on the road and if so, how do you find them?

We fitted some Blockley tyres to a lowly powered Lancia Fulvia 1.3 - they had a lovely period look to the tread pattern and bulging side walls, everything that you'd hope for in a classic tyre and they drove really nicely on dry roads. Then one day I found myself sliding around on an ever so slightly damp road at only moderate speeds and if I attempted to accelerate on an uphill bend the front wheels just started to spin comically (or should that be alarmingly)...

Suddenly they were absolutely frightening, with zero steering feel. Hopefully this doesn't match your own experience, but I'd never purchase their classic radial tyres again!
2006 RHD 997 Carrera (but DDK remains in my heart - also now no longer)
1972 LHD 2.4T with '73 2.4T CIS motor - gone to a new DDK home
1994 RHD 993 Carrera - gone!
1968 LHD 911L - was the Wife's but now in new hands :-(

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AndrewSlater
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Re: The Manhattan Project

Post by AndrewSlater »

gtBen wrote:How's it going here :angel4:
All good here - thanks :)

As for the Blockleys, I have not had any issues with them, but then this isn't really a daily driver so not racking the miles up.
The most dangerous tyre/car combination I encountered was a set of Pirelli PZeros that I inherited on a 997 C2S I bought.
In heavy rain if you drove it above 60mph it would happily aquaplane off the motorway- terrible tyre ( and they fit them to McLarens as standard! ).
The problem was fixed by fitting some Michelin PS2.

As for the car have been making some minor tweaks over the last few weeks including swapping the 350mm steering wheel for a 375mm one - it feels a better size but not done enough miles to tell for sure. I also adjusted the hand throttle as it was pulling a little too many revs when fully pulled on a warm engine - all back to within spec now.
I've also adjusted the handbrake as I suspect the new cables had stretched from new. It now holds perfectly with a couple of clicks.

Had planned on taking it to Goodwood FoS and had a ticket to park at the back of the Porsche stand, but ended up taking the GR Yaris instead :roll: .
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
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Re: The Manhattan Project

Post by AndrewSlater »

Having not modified or tinkered with the car for some time, I was getting withdrawal symptoms.

One issue I wanted to address was the smokey start-up whenever I left the car unused for too long.
Now I know the simple solution would be to drive it more often, but that's not really happened this year.

The problem is the classic problem of the oil slowly migrating from the oil tank back to the sump.
It then seems to find it's way past the piston rings and through whichever outlet port is left open.
The oil in the exhaust then burns off on startup and can take quite some time to clear.
I suspect the problem would improve over time as the rings bed in further, as the car isn't really fully run in yet.

However I decided to fit one of the drain back valves as offered by Rothsport or Willhoit.

I went for the Willhoit one as it is better priced and bought a new genuine Porsche 'S' oil pipe and four new genuine Porsche clamps.

Image

I decided to fit the valve closer to the engine than the tank to try to protect it from debris from the tyre.

After a bit of measure twice cut once I had a replacement 'S' pipe with valve fitted.

Image

After running the engine up to temperature I drained the oil by dropping the sump plate, then fit the new 'S' pipe.

Image

I also took the opportunity to fit an aftermarket sump plate with integral drain plug, as I have a later oil pump fitted the standard one clashes with the integral filter mesh on the pump.

I had tried to order some replacement Valvoline VR1 20W50 oil, but struggled to find stock, so had to plump for Millers Pistoneeze 20W50.

Image

I was a little curious as to how the new engine oil would get to the sump when filling with the new valve fitted.
So I decided to remove the oil filter as I didn't want the oil to backflush the filter and into the sump - at least with the filter off I could monitor this.

10 litres later and no oil had reached the filter level, so it was clearly all sat in the tank.

I decided to remove the distributor rotor arm and disable the fuel pump so that I could crank the engine to build the oil pressure up.
After cranking the engine for around 30 seconds or so with zero oil pressure, I felt a little worried about continuing. :evil:

Maybe the valve wasn't opening with the reduced pressure draw from a dry oil pump.

After contacting John Willhoit directly he said this was normal and to be expected with a dry oil pump. He suggested it was better to remove the valve until I had some oil pressure.
Now that advice to me seemed easier said than done.

So I bit the bullet, dropped the oil again from the tank, replaced the 'S' pipe to the old one ( without a valve ), refilled the oil and cranked the engine until I got oil pressure.
Interestingly the new pipe did have oil post valve so the valve was opening during cranking, so possibly it would have primed with a little more cranking.
Also interestingly I got oil pressure within 3 or 4 seconds of cranking.

Finally with oil pressure, I dropped the oil from the tank again, swapped the 'S' pipe again and refilled the oil.

Now continued cranking showed constant oil pressure. - Yeah! :bounce:

Electrics and fuel pump restored, I ran the engine for 10 mins or so to prove that the oil pressure was all good.

I expect the car will be laid up over winter now, so at least it has clean oil in it.
I'll give it a start-up in a month or so's time and touch wood I won't get a massive plume of smoke as I usually do.
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
deano
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Re: The Manhattan Project

Post by deano »

Nice write-up thanks for sharing. Looking forward to hearing the results! :compress: :bounce: :cyclopsani:
Dean
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