Measuring the bores on my NA 5/99 XK8, and I cannot find a bore specification on wear limits anywhere???

I must be retarded... Not in JTIS???

Help Anyone???

THANKS!!!

 

How thick is the ridge at the top of the cylinder, might give you a feel for the wear.

 

Thanks for the reply Bob!

Certainly there is a ridge above the combustion line, but no discernible ridges otherwise...

Bore measurements to follow...

 

OK...

So I took bore measurements using a dial bore gauge with a resolution of 0.0005". Six readings per hole, top/middle/bottom, parallel and perpendicular to the crank...

Data attached...

Also, I think my readings are a hair high... I rechecked my calibration afterwords and got a 0.0002"reading.. I'll do it again in in a bit...

Max wear is 0.0028", average appears to be around 0.0015"

Whadya guys think???

Thanks!

HS!

 

If you do not have it already, you should find the Jaguar Engine Repair Course Manual,
course #168. It has been posted here courtesy of MotorCarMan. For engine assembly,
it is much better than JTIS.

To give you an idea, the manual says that the pistons are select fit according
to the finished bore during initial assembly. The pistons come in three "grades",
each being 0.01mm bigger than the previous size.

No specific wear guidance, other than if the Nikasil bore is worn, the block
must be replaced.

 

Ah Plums... Thanks yet again helping across the street without getting mowed down by a semi...

Found the 168 manual you were talking about, and yes... it is really good...

I guess it all comes down to whether or not the Nikasil coating has been compromised, not actual bore measurements like NORMAL engines!

I cannot find any areas of bore walls that are significantly different than others... mostly still cross hatched, with a few areas of "mirror smooth"...

There is no direct correlation between compression readings vs. bore measurements... One of the higher compression cylinders (165 lb) was actually the most worn... i.e. the 0.0028" over cyl...

It appears as though my engine build was with all #2 pistons. This gives me piston diameter, but not bore wear of course....

SO ...

Even though I have 100 high res pictures of bore walls... I'll go take another peek and make sure I don't see any "light grey" nikasil wear through... (there's not)

Heads are checked and perfect, decks are checked and perfect... Time to slap this baby back together...

Now back to my head gasket and bolt reconnaissance!

Thanks Again man...

Yer a lifesaver...

HS