Smoke, oil leaks, heat

That are the right parts, but again SCparts is way overpriced as always.

David Manners or SNG Barratt do the conversion kit too. Iā€™d say cheaper than SC parts.

And SNG has an outlet in France.

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Mechanic reckons leak is too great to be driveable, comes out as fast as it goes in (on the ramp, in gear). Does not leak much at idle out of gear it seems.

Regarding the PCV, this may be a dumb question, but does the SII 4.2 actually have one?

The repair manual does not mention a PCV, just a crankcase breather and possibly an Exhaust Gas Recirculation emissions device. I think mine has had its EGR removed but I need to check.

Anyway I am looking now at options to get it trucked back to Paris where I can keep a closer eye on it together with my regular mechanic.

The rope seal is ugly to install. At least, the transmission needs to be removed, the front suspension has to be dropped to lower the oil pan, the crankshaft has to be pulled. That means many parts and while-your-at-it. Engine out probably smarter. If itā€™s really that bad I want to see it!

The PCV has no valves, just a sieve sandwiched between head and the black casting at the front of the head. Blowby is then drawn into the carbs, and burned.
And it wonā€™t cause as much of a leak as you described on its own.
David

Make sure itā€™s not the pan seal: they cause leaks like you are describing.

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How does one explain that?

You said the mechanic replaced leaky cam cover gaskets, then the engine lost oil pressure, then you found ā€œoil all over the placeā€ and the oil loss became significant. It seems very unlikely that anyone would have missed this, but have the oil feeds from the block to the back of the camshafts been checked for leakage?

A long shot I know, but perhaps worth a look.

Frankie

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Yes. We need to know where precisely the oil is coming from, and chances are that you can avoid a really expensive job for now. Does the mechanic know or guess? You can always flat-bed it. Best of luck!

Maybe the mechanic disturbed the rear cam cap seals? Sounds like it needs a good degreasing and a focussed eye on start up above and below.

If for some reason,heā€™s disconnected one of the cam Feed pipes on the back of the head,that would give a bad oil leak and significant pressure loss.

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Correct. Also check that the pipes themselves are not cracked - sometimes happens.

Frankie

And the other end of that same pipe, low down on the left hand side of the block.



A leak at any one of those would certainly run out as fast as it was poured in, but less at idle speed than at higher rpms.

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Thanks again for all the advice. Hereā€™s the update on this saga.

I decided to have the car trucked up to Paris to my regular garage and where I could take a look myself. Hereā€™s the updated diagnosis

First of all, when it arrived, it wouldnā€™t start. Most probably the various people driving it on and off the transporter didnā€™t find the manual choke and burnt out the starter motor. So the first thing they did was swap in another starter (a smaller model used in E-Types apparently but which seems to work well).

Second, and perhaps explaining the starting issue, they diagnosed bad ignition timing. This has never been an issue before so we suspect the other mechanic started playing around with it. Once they adjusted this and had the new starter it started up. This is maybe why I found it slightly sluggish? Maybe he compensated by making the carbs run too rich hence the black smoke.

Third, oil was a grey-brown colour. They are pretty sure head gasket is shot, probably because the bad timing led to overheating. Indeed the expansion tank is pressurised even after shutdown.

Fourth, they are puzzled by the radiator set-up. Expansion tank is acting a recuperation tank and once of the radiator outlets at bottom left is blocked. So the cooling system was not set up properly following the rad change.

Fifth, no great oil leak. This a mystery; the first mechanic told me oil was coming out as fast as he put it in. But this morning I was standing underneath it and nothing. It is certainly a bit oily around the back of the crankcase but we canā€™t see anything major that necessitates taking out the engine.

So next step is head off and new head gasket.

Itā€™s a cautionary tale. It seems it all started because the rad fan was coming into contact with the fan shroud. This caused the fan to eventually unscrew itself and damage the radiator. Unfortunately the new radiator seems to have been badly installed and the cooling system not purged properly. At the same time, to cure the flat spot the timing was messed up and compensated by an overly-rich mix. This caused overheating and oil pressure drop and a (temporary) leak. And the overheating blew the head gasket.

With hindsight, perhaps all of this could have been prevented by a 5 minute tinkering with the fan shroud at zero cost. A stitch in timeā€¦ But who knows, and what is done is done, what is spent is spentā€¦ On the plus side, I will have an engine with a new head gasket, new fan clutch, new radiator, new cam cover gaskets and hopefully correct timing and carb set-upā€¦!

Nick

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Hi Nick,

What an unfortunate storyā€¦ but I guess that a blown head gasket is somewhat better news than a rear main seal and engine out.
The Paris garage seems much more competent than the previous one.
I wonder though, albeit being very probable after the engine overheated, how they are so sure that the head gasket is gone.
Anyhow, refreshing the head and valve-train is a good thing regardless.

Best of luck.

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So to tie up this story ā€¦ the XJC is now back with me, with new head gasket and starter

Anyway there is no major discernible leak, just the odd drip, not really any different from before and not of real concern.

Ongoing niggles: First, oil pressure. Gauge reads about 20 psi on starting cold falling to 10 hot. They have tried different senders but to no avail. They think this is a gauge calibration issue rather than indicative of a real problem. However today after a run, the oil warning light came on at low revs i.e. at 650rpm stationery in Drive, goes out with slightly more revs (e.g. in neutral or park at 800 rpm).

Second, there is a slight noise and vibration under load from the crankshaft. They are not super happy about it but donā€™t consider it to be critical right now. But there is a slightly hard-edged rat-tat-tat-tat-tat. Not very loud but audible in the cabin.

So maybe the bearings are rather wornā€¦

Other than that, running ok.

They advise me to run in the new headgasket for a bit before having the head re-torqued in 700-1000 miles, but prefer me not to do a 500 mile journey straight off.

Thanks

Nick

Not good. My oil light never goes on unless Iā€˜m braking downhill and very low on oilā€¦ it is at slightly above 40 @ 1500+ hot or starting cold and running and it will stay off if I push it below 300 rpm. Check your relief valve!

Keep checking ebay for cheap running 4.2s to save money and enjoy driving more.

NOT a good indication: if the mains are loose, but are shelled early, many miles can be driven.

If you scrub out the main bearings, repair costs go WAAAAAY up.

Yep time to drop the sump and pull some caps off to see whatā€™s what.

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Was it always like that or only now after the rebuild?