Oh-oh! There’s no circlip on mine, and there wasn’t one when I took the engine apart. So now I guess I’ll also need one of those circlips.
Cheers!
Hi,
Well that’t true, but only partially. I have adjusted the pressure lower now as the high oil pressure when not warm made the oil pump shaft jump up.
Now that Peter told me there should be a circlip on the shaft to prevent that I think we are on the trail to fix this. I can increase the oil pressure once I can be sure this will not happen again.
But sure, I’ll put in new shells in the big end within a short time.
I am positive about the crank main shells as they did have an oil bath all the time and I think just the con rod shells and freshly rebuilt rocker shaft were short of lubrication when this happened.
I will take out the shaft and all rockers and inspect, as I was going to replace one (wrong one) anyways. In my logic if there’s no excessive wear there, then there couldn’t be any at the lower end either. The con rods take the most and I’ll sure open them and replace and report back, but maybe just a bit later.
Darn that I did not know about that circlip, it would have been so easy to put it in there last November or last week!
Cheers!
Hi Peter,
Thanks, I did already get one from Roger @Roger_McWilliams and that’s the one I measured and made the 3D CAD model of. Interesting looking wear, on mine the valve itself was fine, on Roger’s spare it had been substituted with a steel ball, like from a big ball bearing. I thought I’d also have some new ones made from brass. I think someone will need these some day. I hope I can get a suitable (spring steel I think) circlip from somewhere. (I didn’t know I needed one before today.)
Cheers!
Hi Pekka, The relief valve does set a sensible running pressure but I suspect it isn’t really needed except at very cold starts. There’s no problem in 80 psi.
Peter.
Just the most critical ones… but I see you’re determined to get it driving again.
Intriguing logic. I utterly disagree.
Good luck.
Hi,
Yes, that’s what I meant, they ARE the most critical ones.
I meant that I can see from the rocker shaft and the rocker bushings very easily if there are marks of oil shortage. There should be some for sure, but I just meant that if they are minimal or none, then the lower part of the engine should not be any worse. How could it be? Bigger forces at play when running? I wasn’t pushing anything, gently running-in, my big mistake was that I ran that steep ramp (and surged the oil pump with cold oil) too fast after starting. And that the pressure relief valve was blocked and the circlip has been missing from the oil pump shaft some 45+ years!
I did have a look at the tappets and camshaft via the tappet cover. No black or dark marks on any of them, nor wear signs of metal-to-metal contact, so it looks like the coating, assembly lube and oil did threir job well so far.
Also when I had the oil pan off I tried all the con rods and their clearance on the crank, it all looked and fealt perfectly normal and tight.
But regardless I think I’ll renew the big end shells as they do not cost that much, they are not that difficult to change and then I can also see how they are.
I think at the moment it would be more critical to get a circlip that would prevent the oil pump shaft from jumping as then I could easily increase the oil pressure and if it will be between 20 and 40 lbs at 2000rpm when hot (the Jaguar spec given in the Service manual is 40-60 lbs at 2.500 rpm, but I haven’t taken the revs to 2.500 except very briefly, I will keep my eye on the oil pressure and report back.)
It is now too, about 25 lbs at 2000rpm when fully warmed up. It’s only that at idle I think it’s a bit low now.
Cheers!
Yes… in a major way!!
Con rods, with no oil supply, are in FAAAAR greater risk of serious damage than rocker arms, and precisely because of far greater forces.
Hi,
Ok, I’ll replace them for sure now.
I adjusted the relief valve a bit, during the first 10-15 min oil pressure was 50-60lbs at 2.000rpm and 25lbs at idle but a bit later it dropped to 35lbs at 2.000rpm and about 15lbs at idle.
I’ll drop the oil pan again and replace the big ends and plastigauge 2-3 main bearings.
I did a compression test:
6: 10.0 bars / 145psi
5: 9.9 bars / 143psi
4: 9.9 bars / 144psi
3: 10.0 bars / 145psi
2: 9.9 bars / 144psi
1: 10.0 bars / 145psi
Now I don’t know what the pressures should be on a standard 3 1/2 Litre MKIV engine but I’m pretty happy with those numbers. 83mm XK STD 8:1 compression pistons.
Cheers!
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Those look like perfectly acceptable compression numbers: I’ll be interested to see the shells, when you change them out.
Also 15/35 is adequate OP.
If, upon inspection, the mains are not scored, no reason to Plastigauge them.
Pekka,
Do you have a Crankies crankshaft or the original Jaguar shaft? I ask because the price of the Jaguar shaft bearing is a eye-watering. The only place that I could get them was FW Thorntons for £400+. Of course if you have the Crankies shaft then you will be able to get the much cheaper GM bearings.
Art
Hi Art,
Nope, I have the original crank of that engine nr #SL2199. It had markings on it to have been previously ground to +0.030" oversize and now it does have the Chevy 350 mains, which only needed the block to have line bored and the rear buck modified and the crank journals cut to match. The Big ends are the same +0.040" oversize that was in there. Now I will replace them and report back on how they look after ca 19 kms (<12 miles) without the oil pump feeding any oil. 
Cheers!
Hi,
Ok, here we go. I’ll also (just like ten years ago with my E-type) take a peek at the middle main while I’m there.
Today ran fine, before I drained the oil and took the plugs out. I had one broken NOS Champion L-10 again, I put NGK’s in there instead.
Cheers!
Wonderful, wonderful cars…
gtjoey1314
Sp… you’ve completed all bottom end repairs?
Hi,
Nope, not yet. I just got the parts via UPS form SNGB. The cotter pins are BSP size for the main bearing cap nuts, on the con rods I have the Ser. 2 XJ6 type ARP bolts and nuts. I drained oil and try to build strength to do this all next week some day, or then the next week, we should have nice weather coming our way (sunny 20 hours a day and +26°C or more, about 80°F) so I may be lying on the porch rather than on the concrete floor in the garage downtown (I don’t have the car now at the cottage, I wanted to have the E-type there, see?
Cheers!
Hi Pekka, be sure to take a close look at how ARP bolts seat on the conrods. My recollection is some applications can have a tiny misfit that prevents proper seating without machining the ARP bolt.
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No machining needed: just a small grind on the head of the bolt.
Hi Roger and Paul,
I don’t remember the part numbers, but I used the same bolts as on the XJ6C (complete rebuild in 2007-2009) and E-type (renewed big end bearings and nuts and bolts in 2010) and they seated just fine. But thanks for the warning.
Cheers!
Hi,
A small update, no new miles obviously, we’ve had really nice weather and our oldest daughter on her summer vacation from Copenhagen, so I have not spent much time in the garage.
So I hope nobody has been holding their breath! 
I did replace the big ends, the strange thing was that on con rods nr. 1, 3 and 5 the big ends looked fine, but nr. 2, 4 and 6 did not! 2 and 4 looked really bad!
And I did check the main bearings, and those closer to the flywheel looked good, but one closer to the front, nr 3. (”KE.3” Between con rods nr 4 and 5, why did they number the main bearing bucks the opposite way starting from the front of the engine?) looked really bad! 
So I am replacing now six of the seven main bearings as I can do that with some fiddling. The rear one, closest to the flywheel seems fine and I would not be able to replace that without taking the engine out again and removing basically everything starting from the timing gear, flywheel, front and rear engine plates as otherwise it’s impossible to get the crank out.
Darn, I just wish I would have realised what had happened and NOT driven without the oil pump.
Cheers!
1 Like
Well, now you know that your earlier statement…
…was what had me worried.
We all live and learn, and Im happy the crank seems to be OK.
A bit concerned with the mating surface of that one main cap, pic nu.6: its mating surface has been crudely hand-filed. Makes me wonder about the circularity of the main bores, but as lowly-stressed that bottom end is, likely not a big deal.