Ok, the verdict is in.
Found the reason the newly acquired XJ sport doesn't run. (Was bought as a parts car but I just can't do it.)
Pulled the plugs and two cylinders have some of the fresh anti freeze which I just added.
Now, do I tear it down and fix this 132,000 engine, OR replace with a 6 month warranty 109,000 out of a 2003 for $1500??
My thought at the moment is to fix.
More than likely would be doing chains and tensioners at the same time.
But in the end I'd know what I have.
What would you do?

 

If the engine overheated originally, you may have more than a head gasket replacement. But I would at least tear it down and take a look before deciding, and I agree that doing the rebuild would my choice if no valve seats were dropped and the cylinders look good.

 

Depends on time, warm indoor space, proper tools. Head job and tensioners if bottom end is good. Should be cheaper and you will know the status . . . 109k is an unknown.

So, rebuild if you are doing the work yourself. Lots of threads on head gaskets and tensioners; many youtubes.

 

If the engine hasn't run and there is fresh anti-freeze in the cylinders then it's more than a head gasket I suspect. Probably cracked head or liner. Rebuilding a high mileage engine is a waste of time (lots of time), and a LOT of money! You can't just stick new tensioners and head gaskets on it - you need to find out why iy blew in the first place. And if I strip an engine, new bearing shells would be a minimum, and at 132k probably a regrind too.

Throw the engine away and put the 2003 in.

 

Your '98 has Nikasil cylinders and is not economically rebuildable. Replace with an used engine or follow your initial path.

Guessing that you are referring to the '02 but it is still not economically rebuildable.

 

It's the 02 we're discussing. So should be a lined block.
I'll tear it down and what I find.
There are other lower mileage donors out there to consider also.
Also, just if anyone is wondering the oil is clean. No anti freeze there.
The hose from the t-stat housind to reservoir had been mickey moused and certainly was a source of a leak. How long it was like that I'll never know.

 

All AJ27 engines (NA 4.0 1999-2003) from XK8 or XJ8 are plug-and-play in your 2002 XJ sedan.

A later engine should have all the updated timing components from the factory.
Earlier engines are fine as long as all the 'known-faults' are addressed before you install it.

I would buy a known good engine and install it before I spent a lot of time and money on a damaged one.

I have a 1999 AJ27 that had failed due to Nikasil problems. I have several cores from working at the Jag dealer when customers brought used engines for install. I had new steel liners installed by a machine shop and piston rings to match in one of the 1999 engines. I checked all bearings with 'plastigage' for tolerance check and assembled the engine.

I didn't need the engine and I just did it to see if it would work. I also have the info and skills from attending Jaguar training so I was not going in to it blindly.

Read through the Jaguar Engine Repair Course Code 168 if you are really set on a rebuild. I uploaded it on the forum somewhere. It is too large to attach to this post. Bearing selection is a real test of comprehension.

good luck with whatever your decision.

bob gauff

 

If I replace I'd definitely be looking for the latest and greatest, an 03.
It there a manufacture date I should watch for to be sure it has the gen 3 tensioners?
I can't see spending $1500 on something then another $700 in parts to do chains and tensioners.

 

August 13, 2001 on the tensioners. Parts using Lincoln boxes and FelPro gaskets are less than $150 for just the secondary.

 

Sorry, double post.

 

The August date would be on the block?
My cars door tag shows a manufacture date of September 2001.

 

The car manufacture date has little or NOTHING to do with the engine manufacture date.
They are NOT made together but are brought together at assembly. The engine is OBVIOUSLY made prior to the vehicle manufacture date.

The engine is made and then shipped to the car assembly plant. There is also the possibility of engine replacement with 'who-knows-what and who-knows-when'. Unless you bought the car NEW or can document all repairs............ You need research.

The date codes and locations have been beaten to death on this forum.

A search will show that early engine date codes are located near the thermostat housing and later engines have it on the left side of the block.

bob gauff

 

Found the threads on date codes for the engine earlier today just need to go look.
As you said, with the cars date being Sept, good chance the engine was built months before.
Therefore, good chance it doesn't have good tensioners. I could just start by pulling a valve cover and take a peek. Not waste time on this one and look for a replacement.
But, they could have been done already just not at a Jag dealer. I had them check the history.

 

The 2002 engine will have the DATE CODE on the left side of the engine block.
The steering rack and pipes/hoses will get in the way of the sight line of the stampings. (mirror?)

The Piston codes, Bearing codes and manufacture date code should all be in the same area. A flat casting area with a 'dot-matrix' type stamping.

A bunch of numbers and letters for you to decipher.

bob gauff

 

Being optimistic and finally having some time i started tear dowm.
Started with a valve cover, low and behold gen 3 tensioners. And I'd have to say they look a lot nicer than the aftermarket I put in the 98.
Lets see what compression looks like.. Just so I know..
Left bank, which is the side where I found antifreeze. 125/90/90/150.
The 125/90 is where I found antifreeze. Hooked air up the these two and blew bubble in the cooling system.
Right bank, no antifreeze. 0/90/90/150
Second exhaust valve hung open..
Continuing to dig deeper.. Throttle body, Intake..
The two center ports both sides, melted. Both knock sensors a puddle of goo in the valley.
Yep, if it got that hot, time to move on.
Maybe this week pick up an engine but with the holiday I don't know.
I'll be back once I get something going.

 

I see this failure all the time. It is usually "well I was ALMOST THERE, so I kept going."
or "There was no place to pull over."

good luck.

bob gauff

 

Haven't bought a replacement yet, but still tearing it down.
Looks like someone thought stop leak was the best invention ever.
First shot was behind the water pump.
It had MLS headgaskets which didn't fail, it was the warping of the head that caused death.
A couple of the cam saddles you can see the wear toward the center of the head.
Cylinder bores on a couple are almost blue from heat.
And the dead cylinder.. Of course a dropping seat.