964 C2 - Rolling Resto

[Bootsy]

Great thread

[rhd racer]

So we kept going and the way it had been built was not helping us at all. Several of the rocker arm bushings had been put in the wrong way round, so we could not easily remove them. This was a particular problem on 1& 4, which we could not get out and thus the cam got caught on them when trying to draw out. A bit of a catch 22, but with a bit of ingenuity we managed to pull the chain carriers back just enough to drove them out towards the rear of the engine.

Not visible in this shot, but we also found some Niloc nuts instead of K-Nuts as we got deeper into the engine, which of course fail as the nylon deteriorates with heat. It all looked like it had been done by someone not really familiar with 911 engines.

[rhd racer]

This is the left bank before we removed the cam. The chains look ok but then everything does when it is covered in oil and shimmering. Apologies for the shaky image, but I took this one to remind me that this was another faux pas by the last builder.

The right bank has an oil fed chain tensioner. This bank has a spring tensioner only, because the tensioner shaft had been put in the wrong way round - so the oil pick up was effectively blanked off. Nice

[rhd racer]

Now I knew from taking the fan housing off that there would be some issues, but I didn't really inspect things until we got this far. It was held onto the block by an interesting mix of hardware, the most unusual was what I call a body bolt; an M6 hex head but with a self tapping thread. I didn't take a picture because I was too busy crying.

Now you might think that it can easily be resolved. After all, it smacks of a sheared M6 in the cam carrier, which was probably drilled out to M3 and the aforementioned body bolt put in. Therefore I have my pilot hole, and what am I worrying about?

Err, well this...



Yes, let's not worry with the centre punch boys, I've got this. I will just stick it here, part stud, part carrier. We will make the 3 mm up later by over-sizing the fan housing cut out.......

[rhd racer]

Great thread

Thanks Bootsy. It could have easily been a very public lesson of 'if it looks to good to be true then it probably is', but I think I have got away with it on the engine. We will save that moment for when the rear quarter comes off

Below is the front pulley, showing the standard bolts used instead of those pesky allen head bolts which are rolling around a workshop floor somewhere!



So, the strip down continued with the heads coming off and everything going into the parts washer for an initial clean. The inlet valves had all been replaced very recently, and the exhaust valves (more commonly changed) were clean enough, suggesting they had probably been done during a previous strip down. I will come back to this later, but initially we took a couple out, inspected the guides and seats and all is good.

[rhd racer]

Amazingly there were no broken head studs, which we were expecting. There is nothing in the history to suggest they have been changed, so I will be upgrading to the 993 versions because it would be both heart and wallet breaking to have one go ping down the line.

You will notice the barrels in the parts washer. All good too, no scoring or marks, totally reusable.



The numbering suggested a fairly recent marking, so had they been off too?

Pistons are good too, good skirts, only a tiny mark on one of them but nothing to be concerned about...



The conrods all looked good too, and Angus is going to weigh them all to make sure all is in order.

But if it had all been apart, why would you re-use this piece of old crud?



We were lucky to get that one out

[rhd racer]

So, time to split the case



Big end shells in good nick - a tiny mark on one (not a score, though it look like it in the pic), and standard size too so not previously ground



In truth, we thought they had been recently replaced.

So it begs the question, if you are going to get that deep into an engine (and you are a business, not a DIY-er with no access to machining services) why would you do all of that and leave this; (remember our old friend from the initial inspection that was causing much of the oil loss?)



And with the chemical metal removed....



Now we heated the case and tried to get it out but it is well in there. So, it will be machined out by the machine shop and then the case built up with weld and re-tapped for a permanent solution.

Frankly, even if you were a DIY-er doing this you would find someone capable of doing this...

[rhd racer]

And then through the parts washer a third time, each time making the sealant softer and easier to work with a blade to clean the case halves without making any marks in them.

I think they look pretty good at this point, 24 hours on from starting with the engine in the car...



So I came home with all the ancillaries to clean feeling a pretty happy bunny

[911hillclimber]

Loving this thread, and an insight to a 964, nice change.
Engine not too bad, just some tidy up required, good going.
Graham.

[jjeffries]

Thanks for showing us all this....fascinating. That poor workmanship beg's the eternal question, "Are you stupid or f-ing with me? Perhaps both?" John

[rhd racer]

There was one photo I forgot to post because everything got a bit jumbled with the resizing last night - the crank.

The mains looked fine, as did most of the big ends, with the exception of this one which is a bit worn. We are going to check it over and see if it can be re-used or if it needs grinding (remember the shells were standard, so we should be able to do a 0.5 grind on it). Again, not too bad

[rhd racer]

Thanks for showing us all this....fascinating. That poor workmanship beg's the eternal question, "Are you stupid or f-ing with me? Perhaps both?" John

It's funny you should say that John. In my best Lloyd Grossman voice (from those that remember Through the Keyhole the first time around). 'Let's look at the evidence..........'

- The wrong locknuts used everywhere
- Front pulley bolts lost and replaced with something inappropriate
- Exhaust held on with standard hex nuts underneath the exchangers, so could only remove with a crank spanner from the side of the exchangers instead of the 'designed in' access holes
- Rocker shaft loose
- Rocker shafts bearings fitted the wrong way round
- Poor drilling out / subsequent fixing of fan shroud
- General lack of care and sympathy with every job completed
- And let's not forget leaving the leak of all leaks in the case when we now know it was all broken down and accessible

Now all this was playing on my mind and I realised I hadn't given the history a check through, so on Sunday night over a glass of Rioja or two I got out the file, which is extensive.

Now all the servicing has been done by the same place for the last 10 years or so - they have done everything, all documented. Their invoice states 'Porsche Specialist', so that was my theory about an MG specialist doing the work and being out of their depth out of the window.... As Angus said though, any company that makes their living doing this type of work, irrespective of manufacturer of preference, should be doing a better job. I am not going to name names, it is not someone that you would recognise from the magazines but it certainly paints an interesting picture.

Now if I was the owner of the car, I would be livid with the final product, because the invoices showed;

1. Handwritten note stating a full engine rebuild undertaken using parts supplied by the customer; crank, one piston, one cylinder, one cam, one cam carrier - undated
2. A more detailed invoice state the parts they supplied (bearings, piston rings, plugs, gasket kit, clutch etc) and the labour. Totals £3300 (presumably ties into point 1) - dated late Jun 18
3. An invoice from a 3rd party machine shop for a crank grind and shells - £750 odd - dated Dec 17
4. An invoice from the same machine shop for head work - new valves, guides, re-seat all valves £350 - dated Nov 17

So I am taking all this to mean that the work was done in one go, and the rebuild went on for some months end to end. The killer blow is in item 2, and I quote;

Chemical metal £7.50

So they charged for the chemical metal to gum up the damaged case!

Given the scale of the oil leak, and the obvious expense that the PO had put into it (perhaps £6k inc his parts, maybe more?), I think it was probably the final straw and he put it straight up for sale. I saw it first last summer, so it all ties in. I suspect everyone that went round saw the oil everywhere and ran away, which is why it took such a long time to sell and the owner had to slowly adjust his expectations. Feel for him though.....

On the plus side, the history turned up that one of the rear wheel bearings was also done last June, as was the battery, so that is another couple of things off the list.

Oh, and it has a cat bypass already - tick
And a rolling road read-out showing 265bhp - I will take that with a pinch of sale as it is old, and I would be amazed if only a decat would do that, as everything else is standard. And of course the all important alignment check from when it was damaged back in the day.

So in summary, the 964 at the bottom of the internet had a rebuilt engine, but had just been done without any real care, and for a few hours more and a couple of hundred quid, could have been twice the car it was at the point of sale.

[DustyM]

You mention a crank grind there, but earlier that it was on standard bearings? Something not right there.


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[rhd racer]

I think it is my terminology Jon.

The rod journals were ground 0.5, and the big ends not, and on new standard shells (stamped STD). We are going to measure everything to check (as trust is definitely low!), but my hope is that the big ends can be ground 0.5 too and oversize bearing shells to match.

Or there is another crank somewhere that found itself in the recycling. Or they used the wrong shells with this crank!

[Daveuxb]

Think its unlikely that crank has been cround 0.5 undersize with std bearings. Every bearing would rattle around badly it would cream the rods and crank in no time. Never had a set of standard bearings stamped wrongly but theres always the possibility. Either that or measure the the journals again and grind to 0.25 if out of the wear specification otherwise polish them. Installation sizes were 54.971 -54.990 Visual inspection of 54.960 wear limit.