I just noticed the scroll on the crank is right up against the rope seal.
It is not very deep, but if you drop the crank in without “sizing” first you will not have the seal being compressed by a nice smooth surface. The seal will have small ridges. As soon as the crank is running it will flatten those ridges. Is that a problem, does it tear up the seal surface ?
Do other engine makers have scrolls against a rope seal ?
Maybe Jaguar worried about that scroll thing.
about the liner, for many years when i got a stuck seized liner, i’d just bore it out ,a few cuts at a time !.
when it got thin enough just use a screw driver in collapse it inward, just fall out on the floor.
course a clean up with a ball hone,
Oh dear, forever anal. Had to look up the 100 photos taken back in 2005 when I rebuilt a second hand HE V12 for the coupe, to check that indeed the scroll was on the rope seal. From the photos sure looks like it, so I did not have hallucinations after all.
That particular V12 engine I bought from a member of the local Jag club who liked racing his XJ-S. He had bought the engine with intentions to race but never followed through. He had at least taken the heads off.
By chance I noticed there is a photo of the block with 2 studs missing. No recollection of that, no idea why the studs were missing. I don’t think I took them out and I know from rebuilding my pre HE V12 many years before they are no easy item to remove. That engine was just normal level of grubby inside so I had just about every part tanked and the water jacket was way cleaner afterwards compared with the engine I have now which has deep orange discolouration. Generally that V12 was in good condition, only the usual wearing parts and gaskets needed to be bought for it.
A later photos shows a full complement of studs so I must have bought a couple and fitted them, probably with Loctite. They do not look bright and shiny, must be second hand.
Never had an issue: I always used gun grease on the seal, and hand spun the cranks to get them “set.” Never recall any tearing of the seal, and almost always was pretty leakfree.
This was on all kinds of engines, from Jags, to old R-R 6 bangers, from Triumphs to 3- liter Rovers, and not just a few older Ford and Chevy engines.
It was a technique taught to me by Dad.
Hi Richard
Pity you didn’t ask me about this when you came to see me?
I use a vice to squash the seal a bit. Then fit it in the block with a thin smear of silicone sealant in the groove in the block. With a 1/2lb ball pein hammer, start from the centre and tap the seal well down into the groove.Try to tap it as a radius.
Some of the after market seals are too long so you may need to trim the ends. Leave them a tiny bit proud. Coat the surface liberally with grease or “Rocol”
Quickly fit and torque up the crank.
Repeat the above in the rear main bearing cap.You will feel an increased resistance as you turn the crank but it shouldn’t be excessive. If it is, it could burn the seal
On initial start up!
We always used this method. The guy that taught me all I know about V12s in works engine recon, NEVER used the sizing tool!
There was one under his bench covered in years of dust! He also showed me how to replace the rear seal without a complete engine strip but that’s another story!
Nigel Boycott.
Thanks: it’s not just me!!!
Crankshaft bolted down. Without rear cap fitted the end float is 7thou, which is 1thou above spec but not worth hunting for oversize thrust washers.
I measured the torque to rotate the crank, it was about 0.5kgFM…
After fitting the rear cap which brings the rope seal into the equation it was 1.6kgFM.
That does not sound much, and in fact if you have a 1M torque arm it is a breeze to turn the crank.
Last week I had tape on the crank to “size” the seal. The rear cap was bolted down for 10 minutes, then removed. Two days later got back to it, removed tape from crank, and dropped the rear cap in position. It stuck 3mm from home. Obviously the seal had expanded somewhat as nothing else would make the cap stick. So the cap was eventually bolted down tight again.
Maybe the “sizing” technique needs a very oversize tool to be effective. I suppose with a bit of experiment you could work out the right tool diameter to make it a worthwhile exercise, but looks like just bolting down the cap onto the seal is as good as it gets.
I have rebuilt a couple of V12s before and the first one simply bolted the cap onto the seal and it did not seem tight. The second one I had tape on the crank to “size” the seal, and that also was not noticeably tight.
This third engine it feels tight but I guess it is normal. Quite likely early seals had asbestos but that material is verboten nowadays. The substitute material could be a bit different when compressed by the cap.
The tools mentioned in the workshop manual are what I guess Jaguar used in the factory for assembling engines on a production line using skilled and semi-skilled personnel where speed was essential I do not have any of them but it is no problem to find ways of assembling without them.
Richard
You’re not concerned that the end float is above spec ???
The thrust washers are available and now is the easiest time to fit 'em…???
I wouldn’t care either. It’s a bit more important with a manual transmission as operating the clutch pedal pushes the crank forward and excess play results in excess free play in the clutch pedal, but you’re not gonna notice a single thou.
Yes…that was my concern as I have a 5 speed Tremec on the back end of my V12…but you have to wonder why the original designers decided on an upper wear tolerance…hopefully for a reason…and during a rebuild is the easiest time to replace the thrust washers on the centre main to get back into spec…
They are available …
Agreed: a thou isnt much, but it is above spec. If oversize bearings are available, I durn sure would fit them.
End float spec is 4 to 6 thou on assembly.
The thrust washers do not seem to wear much, this is third V12 I have stripped and I have reused the OEM ones.
A consideration is if end float is excessive it means the conrods run out of room to move as the crank moves, tending to bend the conrod. I would reckon Jaguar engineers left plenty of tolerance up their sleeves on this issue. They probably built in an allowance of 5 thou or more wear on the thrust washers.
I am happy with 7 thou end float. This engine will eventually go into the convertible. This car is on what we call “Club Plates” meaning it has very cheap annual registration fee ( $70 instead of $700 ) on the basis the owner belongs to a registered car club, the car is over 25 years old, and must not be driven more than 45 days in a year. A log book must be carried in the car and an entry made every day it is driven. I drive it no more than 20 days in a year, and that is 2,000kM max. Cars on club plates are generally hobby cars and not driven much.
I seriously doubt even if I sold the car it would revert to a daily driver. If the rebuilt engine is well maintained It will be good for another 200,000kM and make it to the 22nd century. In fact the present convertible engine at 130,000kM is still strong and after 10 years of ownership never given any sign of wear or tear. The viscous clutch gave up once, no other engine mechanical issues apart from very minor oil leaks…
Richard
1 thou is no issue at all. Don’t waste your money on an oversize thrust washer for a thou!
Best Regards
Nigel
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First piston I tried to put in the block gave me no end of trouble.
I used the ring compressor bought 40 years ago and has been used often
The compressor is actually an Australian made one and definitely top quality.
( We don’t make that sort of thing here any more, 99.9% of any tools you buy are imported ).
I just could not get the first oil control ring into the bore. No matter how hard I tried to hold the compressor against the lip of the liner as the piston was pushed, that ring would pop out between compressor and lip.
The brand of the rings set is “Grant” made in U.S.A.
Unlike the OEM oil control rings which have a square section, the Grant ring seems to have a radius on the outside edge which might make it easier to slip into the bore, but it also makes it easy to pop out of the compressor.
The only way to fix the problem was to make a clamp as shown below to hold the compressor hard against the lip. That worked.
Regarding crankshaft end float, looking into the bottom end you can see there is a fairly large gap available at the small end on many conrods, so a few thou over the 6 thou end float spec should not bind any rods.
I will take a closer look because on first installing all the pistons there was one rod with a very small clearance.
Since then I have torqued all the big end nuts to spec and rotated the crank, so that might have changed things. There are other reasons why you would not want excessive end float.
For the record the torque to rotate the crank is 16kgFM static. It drops to 10 - 12 once the crank moves.
I will check it later when the heads are included.
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Greetings All,
Any reason you wouldn’t take a die grinder and use it to run a line to to bottom?
You might have to explain that suggestion in more detail so I can think of a reason.
Tried to delete my response.
It was originally in reference to removing liner, and clearly you are way past that.
Understood, but a drastic way to extract a liner.
It is a matter of getting a very sturdy couple of studs ( or one even bigger stud ) and a lipped plate at the bottom end of the liner.
From there it is just grunt to pull it out.
Hi Richard
I use a Blue point ring compressor very similar to yours. Have the newliners go a slight taper at the top. This would help. Easy to create by hand with a scraper on an XK engine. Never tried to do it on a V12. Every liner I’ve ever seen has a slight lead at the top.
Hi Nigel,
All the liners have a chamfer of about 1mm around the top.
My problem appeared to be the radius on the oil control rings.
Once I clamped the compressor tight against the lip of the liner I could easily get the rings into the bore.