I have been in trouble with my series two engine for a while and it needs to be replaced. Series two have a serious inherent cracking fault between the bores - ask me how I know! Series three are expensive at £2000 or so, which is far more than I want to pay. Now, I need to get the car back on the road, if only for a short while. So, I have come up with a ruse! Given that the older series engines had short studs, do you think it feasible to tap out the block clearance hole, 0.450 inch diameter, to take a helicoil repair and then use a short stud. The outside diameter of the 7/16x20 stud is 0.440 inches?

 

the men who can answer that would be TilleyJon or George Camp and they are in the MK-2 / S-type forum.

 

A guy on this threads 4.2 long stud had short studs fitted by a PO

https://jec.org.uk/forums/viewtopic.php?t=5661

 

Thinking a bit about it if it's a short term solution you have nothing to loose trying a short stud, It's a hell of a lot of hassle removing snapped long studs from the base of the block. Excuse my terminology here as i'm not an expert, It would most probably provide superior clamping compared to a corroded/Stretched long stud. It would be worth finding out the differences between a long and short stud block ie: Did they remove block material/Strength to accomodate the long studs? I've read that a long stud block in good order is stronger than a short stud block as the clamping forces are moved from the block deck to the base of the block.

 

Well. I've ordered a helicoil kit to attempt the repair. I also have my eyes on a slotted block that could be the basis of a re-build. It does not have main bearing caps though. Can I use those on my current 4.2 engine?

 

If you use main caps from another engine you need to get them checked/ Line bored on the slotted block.

 

I don't think there is enough "meat" in the block deck on the long stud engines to take a short stud. Obviously you can try it, but you need quite a length of thread to make it work.

Why not investigate installing lipped liners to your existing block ? These are available and a good engine rebuilder should be able to install them. The lips cover the top of the cracks, and thus cure the problem of frquent head gasket failures.

If you have a slotted block without bearing caps, (which is a bit of a puzzle as to why), it is quite an involved job to fit the ones you have and then line bore. It's normally done by machining a few thou off the caps, bolting them on then line boring. Better to find a block with caps IMHO.

 

+1 . . . Been there; done that; and Fraser is dead set spot-on. Two engines done some 10yrs ago still going strong . . . now ready, if necessary for a third on a Series 2 XJ6 (not mine). Simple job for an appropriately equipped shop. Lipped liners really do solve the problem and seemingly, overcome the bore cracking forever!

Another huge benefit I had not considered on those previous engines is this . . . provided your pistons are in good condition and measure up near specs for wear, ovality, ring dimensions, then purchase new matching rings and you are good to go. Remember to "gap" the compression rings to spec, or get your machinist to do it for you . . . perhaps the most overlooked step in engine rebuilds.

Swapping bearing caps is a definite NO! For a start, there will be no virgin metal to allow re-lineboring . . . for that, you would need a virgin set of caps which in years long gone, Jaguar would supply to special order, but which today are probably rarer than rocking-horse poo. Hence, each of your caps are numbered and must be matched against matching numbering on the adjacent face of block. Ditto for camshafts.

HTH and keep us posted,
Cheers,

Ken

 

Blimey Ken, Ive read a few of your posts and you really know your onions with your enviable past jobs working on the compacts in competition etc, I now know who's ear to bend if i run into any problems! Love the MK1 pics in the starter motor thread

 

Align boring of main bearing seats has been done for decades. With the right equipment and a skilled machinist, it can and does work.


But, think about the process. It is flawed. The "new" caps were bored to mate a different. It would be a "miracle beyond belief" if all aligned as they came.


So, the caps are ground on the clamping surface. Now the bearing seat is no longer round. The ones in the block are still round to tolerance. The mated caps to block are as irregular as can be. The Cutting tool seeks to align all the "holes" and make them round.
The former, yes, the latter nope! Close, yep, but yet a bit egg shaped!!!


Carl

 

Aaah gosh [blot] you are too kind . . . now I'm blushing . . . must be rubbing off from [Grant Francis] and all his JD I have managed to corner when he has his back turned. Now, there is a real guru . . . the Wizard of Oz. But, coz you were so kind, Here's another tidbit of trivia from back in the day . . . painted wire wheels such as adorn your gorgeous Mk2 (3.8L?), provided they were not over-sprayed chromies, were far rarer than rocking horse poo.

Yes; chromed wire wheels (CWW) were fairly common, almost a default on the sports Jaguars, but specifically banned from any and all competition by our regulatory bodies (CAMS & ARDC) as elsewhere. Don't bother looking for them on competition C or D or even later E-Types. I think the issue was that the chroming set up chemically induced stresses that saw some horrific wheel failures in races. Much of the world had similar bans, but for a short time, painted steel spoke wheels, later stainless, were exempt. Reason I recall so vividly is that pre-race scrutineers used scrapers to check. Many a Jag, MG, Moggie etc driver/owner became quite upset at all the paint scraping! Not sure what the historic racing crowd face today . . . I know many have alloys but perhaps the WWs I have seen use stainless spokes? Anyone know for sure ???

I confess, I haven't seen painted WWs such as yours for many a year. BTW; if ever there was a car just made for that icy blue colour, it has to be the Mk2 Jaguar. I bet you just love it to bits. I'm so envious of your Mk2, my fingernails are falling out . . . the "spats off" look is making my heart race . . . if you tell me it's also a 4spd + O/D, I'll just feint!!!

So [blot] . . . ask away. Let me dazzle you with how much I don't know or (increasingly) how much I have forgotten. Plenty of good mates here who will fill in any gaping holes.

Cheers,

Ken

 

Hi Ken, Thanks for the complimentary comments about my MK2 and the offer of your ear! A bit of a thread drift here, I hope the OP doesn't mind! It's the 5th i've owned over the years and i plan on keeping this one. Yes it got an all synchro/OD box in it but was a factory auto originally (At least i can pull the box out with the engine in!) Ive put a little bit of info in my album. Thanks, Scott.

 

I have now sourced a 4.2 litre series 3 Daimler engine. It turns over, so is not seized but will need to be looked at before installation. Should get it toward the end of the month. I am still going to collect the slotted block. As for re-lining the bores of my engine, I have had a point blank refusal to do it from my usually very helpful expert.

 

This feels like revisiting a past life. However, I did install the series 3 engine and used my series 2 carbs rather than the fuel injection system that looked decidedly iffy. I have it running quite well although it does not seem to be as lively as the old engine. This may have something to do with the carb needles and fuel requirements. But, whilst driving in not so good light, I found that the dipped lamps would not illuminate and there were problems with some of the side lights. It must be the lamp switch said my mates. I obtained a replacement switch assembly, guaranteed to be in good working order, and undertook the change over. The new part had different wiring and hence would not fit. So back to the old one, I gave it a real flooding with switch cleaner and exercised the mechanism. I assembled the cleaned switch - much better but still no headlamps - but I had all four on main beam. At long last, with a mate who knows electrickerey, he was an aircraft fitter in the RAF in an earlier existence, we established that I had swapped two leads over on the headlamp relay! AND I SWAER THAT I HAD LABELED THEM ON DIS-ASSEMBLY!
All is now at relative peace in the world, until I try to get the good lady to drive it that is!