I was catching up on Jose's thread on the work on his car, specifically the engine.
I'm at a very similar stage on my S Type with the engine. My engine ran briefly when I bought the car but hasn't run before that for 8 years or so.
Engine is out and disassembled. All bits cleaned up, bagged and labelled;
There was some water in the sump. The oil pipes from the oil pump had surface corrosion. I think the water is due to a chunk of the rear of the timing chain cover waterway from the pump to the block having corroded away. The timing chain cover is with an Aluminum guy being welded/repaired at the moment. As is the water rail which had some very heavy corrosion/pitting in a couple of places.
So the question is what to do next. I've reached the limit of my abilities! Here's a summary of what I see;

There is very light scoring on the pistons (left/right surfaces, not front back) and the cylinder walls. The pistons have +20 on them which I presume means they're oversized so the engine has been re-bored once. All piston rings in one piece although several were stuck and gummed up
The main bearings are marked +10 which means again I think that the crank has been in the machine shop once before. Some of the crank journals have a small amount of corrosion at the edges of the bearing surfaces. I can feel some small un-evenness on the main crank journal at the front of the engine. I checked the end float before I removed the crank and it was within 0.004''
There is a little play in one of the pistons small end/gudgeon pins. There is some corrosion evident on some of the gudgeon pins either side of the small end bearings but they move very freely.
I've taken one of the valves out and there seems to be a little play between the stem and the valve guide.
The surface of the block still has the letter stamps on it adjacent to each bore so it looks like it hasn't been 'decked'. No cracks anywhere. Blew out huge amounts of rusty crap from the block with a pressure washer after taking out the freeze plugs.
I've checked the bottom of the head with an engineers' straight edge and it looks true and flat.
There doesn't appear to be any wear on the timing sprockets or camshafts. Very little wear on the timing chain guides/tensioner.
There was wear evident on the distributor/oil pump drive shaft gear/cog
I checked the oil pump according to the WSM and the clearances were within tolerances, but a new one is only 90 quid, so I was thinking of replacing this anyway

So, load it all up and take it all to a machine shop for appraisal? Block, crank, bearings, pistons head and camshafts? The whole shebang?
Would they usually charge for an appraisal?
Do they usually supply new bearings, pistons etc if required or would I purchase these?
Should I be concerned about them knowing enough about the XK engine or will this engine be a run of the mill job for a decent machine shop?
I'd like to put it back together myself. I think I can do this. I need to keep the costs down to a minimum but don't want to skimp on necessary items

 

Can you post a photo of the bores? There should be a crosshatch pattern, if that is there, that is good. vertical marks may not be too bad. If you run a fingernail over them can you feel a groove? Or is it more of bit of burnishing that isn't really material removed from the bore?

Yes, the pisons have been oversize, and the crankshaft ground undersize. The pistons are odd, I've not seen a oil ring under the pin before. The specs are in the manual for the side clearance of the rings, you should measure that with a feeler gauge. Typically the rings will rock back and forth as they go up and down in the bore and that opens up the groove in the piston over time. Too much rocking and the engine becomes an oil burner.

Wouldn't hurt to take it in for an appraisal, obviously you want a shop experienced in the XK engine. Sorry I can't suggest one near you. The camshafts were made of very good material, they are virtually indestructible, and essentially never wear.

You can certainly assemble an engine yourself with basic handtools and a few specialist tools. Obviously you need an inch sized wrench and socket set, torque wrench, timing chain tensioner tool, camshaft setting gauge, and piston ring compressor and piston rign installer pliers. There are other nice to haves, like a tap and die set to clean up all the threads. Most are UNF, the ones into aluminium are UNC. Pick up the Jaguar World XK engine rebuild book ( the yellow one) it's a good picture guide.

 

paddy my engine looks very clean inside, as in oily shiny metal surfaces, other than the bottom surface of the sump with the milky stuff. The timing chain, the adjuster, all look clean and not worn. But the crankshaft is worn and 1 bearing spun. So rebuilding it is next.

 

That engine looks in pretty good condition to me. I would have the crankpins mic'ed. Bores checked for taper & ovality. Print out docs I've posted to Jose's thread. You could well get away with a crank polish & new bearings & rings & a light honing of the bores.. Pistons look good. Check thrust side for heavy scoring. The one piston we can see the side of is fine.

You won't know until it's been measured but I recon that can be saved with no major work if it measures well.

Might be a good idea to watch/monitor the measurement being done.

 

Paddy, if there is play in the gudgeon pin, there shouldn't be any, consider new pistons and new pins.
New piston's will have new wrist (gudgeon) pins.

Also consider custom made pistons, they will have a very short skirt and be lighter then the original.

Lighter pistons will have less stress on the crank and rods.
The short skirt will have less friction on the bores and the engine will run cooler.
Short skirt pistons are forged out of round and become round under normal operating temperature.
The aluminum alloy in custom piston's is leaps and bounds better then old technology in original piston's

I have some custom piston's in my 51 Mark VI Bentley, best things I ever did.
My guy at my machine shop wouldn't have anything to do with the antiquated Rolls Royce piston's.

Ross Racing piston's, I'm sure there is a place in the UK that can do the same,

Ross Pistons: High Performance Import & Domestic Forged Racing Pistons

At my machine shop, they can usually supply the bearings, rings and wrist pins will be included in the price of the pistons.
Hastings rings have been in the business forever and are the go-to product.
Fel-pro gaskets and seals.

Bearings are made by a number of manufacturers and will be made to modern standards, so that's not really an issue.

 

The block looks in amazingly good condition ! I see you have found the syndrome of corrosion of the timing cover where the coolant passage is located. I had this on my XJ6 engine ! If you do decide to lightly skim the block to resurface it, don't forget to bolt on the timing cover, as it also forms part of the headgasket seal area. If you don't you may end up with a lip that prevents the head gasket sealing properly at the front.
If you've done any engine reassembly, an XK is reasonably easy, although the rear rope-type oil seal can be a PITA. It might be worth it if you can convert to the aftermarket lip-type seal, but you need a competent machine shop to machine the crankshaft where the rope seal sits. I suspect this might be a problem in southern Ireland due to the rather low numbers of Jaguars sold there, so there isn't a shop that has the experience of doing it. So maybe stick with the rope seal !
BTW, you'll need to buy a heavy-duty engine stand if you want to assemble the engine in comfort, and also maybe an engine crane or hoist. Jaguar engines are very heavy

 

I was warned off buying a new oil pump mainly because the old one which you say is in good order would have been made in the UK where as the new oil pumps are foreign made and the tolerances are not as good as even a worn original oil pump. I had mine stripped and cleaned as they were doing the engine machining and it was found to be in very good condition.

 

In preparation for when I get to the engine, I've been looking around for a UK supplier of modern pistons. From what I've seen, there aren't many options. The best seem to be Wossner and Arias. The Wossner can be/require machining of the crown. Apart from those, there's Rob Beere, the products are excellent, but expensive, and he doesn't list anything for a 3.4.

If anyone has better ideas, many of us would like to know of them.

 

Or, regarding the slightly loose small end on one rod. Replace the gudgeon pin & small end bush on that rod. Do all the small ends if it makes you happy. This of course precludes wear of the piston gudgeon pin bore itself which is unlikely.

There are always some who are parsimonious themselves but happy to spend your money

I think this engine has been fairly recently rebuilt just looking at the crank etc. Possibly not in time but rather mileage.

Be guided by the measurements. If it needs a rebuild do it. If it does not don't ~ baring bearings, rings, light hone. (and small end)

Are you going to do 130,000 miles with this car? I think it would still do close to that in present condition

I did a total blueprint rebuild on my engine because it was a genuine one owner car with 90K miles on the clock unopened. Most measurements were out at this mileage. Yes while apart balanced the crank & flywheel & weight matched the pistons & rods. A very thorough rebuild that included Plastigauging every bearing.

 

I refurbished my original oil pump to spec. Works fine & oil pressure is closer to 50 lbs fully warmed up than 40psi

 

Thanks for the responses and guidance.
So I'll look at keeping the existing oil pump.
I've found a respected local engine guy and will get the bits off to him with the spec sheets.
No, Glynn I wont be doing 1300000 miles but I hope to get a few miles on there! But I take your point. This car is not going to be concourse or perfect at all.. I just cant afford that. As much of the car as possible is being refurbished (by me) not replaced and that includes the interior as well as the mechanics. If it doesn't need new pistons etc, I won't be replacing them
I'll post some more photos of the pistons and bores at the weekend. As with most things they don't look as good when you get close up and personal.
Fraser, yes this engine is a heavy beast. I took it out of the car a few months ago so used a big crane and the stand I'm using is a heavy duty one.
There was thread not too long ago about the oil seal and I'm going to stay with the rope I think.

 

At one time, the UK Jaguar Enthusiasts Club had a hire facility for the Churchill rear oil seal sizing tool. When I did mine, I never used one. A chap I bought my replacement block from, (no cracks !!!), told me to wind a couple of turns of masking tape over the crankshaft oil scroll where the seal sits, then put the crank in, then bolt up the oil seal halves with the seal pressed in as far as possible, then turn the crank around until it moves reasonably easily. Then remove crank and oil seal halves, remove tape and reassemble the engine. It is very important that the seal doesn't drag on the crankshaft, because this will heat up the crank so much it can melt the rear main bearing and then it is "end of engine". This advice was given by Ron Beatty who worked at Jaguar in the test department.

 

This is wise advice. As I said in Jose's thread "rolling" in the seal with no trimming at all but either the tool or the crank works a treat. We had both & I have a nice dry seal that does not leak. Have done a friends using only the crank & its fine. You use a wooden hammer handle for much of the settling of the seal.

Sizing the rear crank seal:

 

Paddy ~ all I'm saying is be guided by the measurements & your eyes. Don't replace perfectly serviceable parts. Yes photos can sometimes flatter the subject. We are now in a position that we can buy a new 3.8 block at a price. I would have to be pretty hard pressed to be persuaded to do that.

 

So here are some close ups of the pistons and bores. Hard to get a good photo of the bores.... There is no noticeable lip at the top of the bores. The scoring on the pistons again can't really be felt much when you run your finger across them.


No 1

No 2

No 3

No 4

No 5

No 6

No 1

No 2

No 3

No 4

No 5

No 6

 

When I rebuilt my 4.2 engine, it had no lips on the bores, and measured up OK, so I just bought a 'Flexhone' honing tool that could be used in an electric drill. This then gives a good surface for new piston rings to bed in against. I can't comment on your pistons, as I had a set of new ones supplied with the replacement block. Yours don't look bad, to be honest. Its not as if you're going to be doing 24k miles a year in the car.

https://www.pacehigh.co.uk/index.php...gory&path=6767

 

That's light scoring, not too bad. If you have access to a lathe I'd be tempted to skim 0.001" off the piston diameter where they have rubbed in the bore and reinstall. Alternatively, the flexhone mentioned above could be used to take a bit out of the bore, but I'd rather not do that. The reason is you have good cross-hatching, and that is a big factor in what determines the oil consumption of an engine. Both the angle and depth of the cross hatch is very important

 

Be guided by the measurements. Bores still show honing marks. I would give them a light hone to bed in new rings. The pistons are difficult to evaluate. It's hard to say whether the car was run after standing for a long time with minor rusting in some bores. I would like to see the pistons polished on their thrust side where the markings are. One can still see the piston horizontal (rotary) machining marks through the vertical marking on them. The markings are only really on the skirts & not the crowns (above the top rings). The most abrasive thing I would put near the pistons is 400 grit water paper only where marked & aligned with original machining. Do it wet & gently. You can try Brasso first if it makes you more comfortable but I think some of that light scuff is beyond Brasso.

Ball end Flexi Hones work very well. This engine does not have much mileage on it post rebuild.

 

SNAP Jagboi ~ identical timing.

 

And even better we are both saying about the same thing! I think those pistons and block are savable without the need to visit a machine shop.

I hadn't thought of sandpaper, but that would work well too. Not much metal needs to come off. Brasso probably isn't aggressive enough to do the job.