And so it begins. Restoration of 1975 XJC

(Lovell) #41

If it came with one fine. They didn’t used to as far as I know.

(Eric Feron) #42

For the record the markings on the pistons show :
846 F. Does this mean anything to anyone?

The engine number is 8 L 2777 . Damn, I thought there was an S in there somewhere, ah well…

(Paul M. Novak) #43

The engine number is 8L27778-S.

You just need to clean off more grease and dirt.


(Eric Feron) #44

Ah I see… :slight_smile:
I checked my paperwork and yes indeed, 8L27778-S

(Eric Feron) #45

Ah well, block is cracked… :frowning:

(Frank Andersen) #46

Ouch, Eric…:frowning:

xj6 85 Sov Europe (UK/NZ)

(Eric Feron) #47

Is there any truth in these possible fixes?

(tonyj) #48

Hi Eric, my 76 XJC had severely corroded cylinder head studs, but after stripping the engine, turned out the block was not cracked. I still went ahead and had it machined and top hat liners installed because I’m planning on keeping the car and wanted to ensure the original block could be used for many years to come. My only advice would be to find a machine shop that is very familiar with Jaguar engine blocks.

(Eric Feron) #49

Thanks for this. Where did you get the top hat liners from?

(Eric Feron) #50

Found this rather useful article. May be the way to go instead of buying another possibly cracked block. I suspect the machining work will not be cheap…

(Eric Feron) #51

Tony, why is it important that the shop be familiar with Jag engines? Just a big lump of cast iron no?

(Frank Andersen) #52

It expresses personal opinions, Eric - block cracking is not as common or unavoidable as the writer implies…

Preemptive modifications to liners, as Tony did, relevantly addresses one area of concern. However, done before cracks appeared, there is no way of telling whether cracks would have appeared downstream. Or whether cracks may develop in other areas…

Block crack repair is highly specialised work, and success also depends on crack location and extent. So where is your crack (no pun intended)…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

(Eric Feron) #53

The crack on this block is between cylinders 3 and 4.

The original block was cracked between every cylinder.

It seems to me that top hat liners is the way to go.

(Eric Feron) #54

It turned out that the crack is in one of the liners, not on the block (as I first thought).
I wonder if this would the right opportunity to replace all liners with flanged ones, or just keep it simple and replace the cracked liner.
Any expert advice?

(Paul Wigton) #55

Given the high opportunity cost of the cheaper fix, failing later, an abundance of caution might indicate replacing all, now.

It may save tears later, and you’ll only be out the cost of a full set of liners and the machining work.

(Frank Andersen) #56

A cracked liner is most unusual, Eric…

If money and time is no object, and the expertise to do the job is available the choice is easy. And as you should to change all the liners anyway…

But I’m curious as to why the liner cracked…

xj6 85 Sov Europe (UK/NZ)

xj6 85 Sov Europe (UK/NZ)

(Eric Feron) #57

Now, here another take on this.

The original engine block sitting in the garage is cracked between every single cylinder. If I go with new top hat liners, I am thinking I might just as well go with the original numbers matching block!! It will then even get its own original matching reconditioned c/head.


(phillip keeter) #58

Great project. IMHO, the “numbers matching” thing is a bit over done. Just a period correct power plant seems like enough.
Keep up the good work and thanks for posting.

(Eric Feron) #59

Hi folks

The machine shop is quoting me $1,000 in labor to fit the flanged pistons bore/hone the liners to fit the pistons (will reuse) and deck the block.
I find that quite high? Am I miscalibrated?


(Paul Wigton) #60

Wait…let me get this correct: you are installing new liners, but using old pistons???