The compression in my 1999 XK8 has deteriorated in two of the cylinders so badly that driving it is no longer a pleasure, and forget about getting it smogged. The solution proposed to me by “my mechanic” who is a generalist and has no particular expertise with Jaguars gave me options. Rebuild the engine. Not particularly recommended by him. Replace the engine with a re-manufactured engine. He couldn’t find any. Replace the engine with a rebuilt engine. This latter seemed the most attractive course, and that’s also the reason I’m writing. Rebuilding my engine is possible if we can find someone to do it.

He called a dealer located over in the next county and determined that a rebuilt engine was available. The next question from the parts lady was “Is it equipped with EGR?” It is not an EGR equipped engine. My question was then: “Can I use their EGR-equipped engine in my car?” Her answer- “Yes, you can.”

The above back and forth went on over a period of a week, or so. Then it got tricky. After I decided to go ahead with the EGR-equipped engine “my mechanic” called to order it and meanwhile proceeded to remove the engine from my car so he would be able to get me back on the road expeditiously once the replacement arrived in a few days. And this is when things got really interesting.

He was then told by the parts guy when he called to place the order that we can’t substitute an EGR-equipped engine for a non-EGR engine even if we attach the EGR parts or block the EGR port(s). At this point I didn’t know if this was impossible to do or was he just sharing church dogma from the home office?

And that brings me to this forum.

I assume that the engines are physically interchangeable but possibly not functionally interchangeable. So, my question is: Can I make use of the EGR-equipped engine and what will it take to do so, besides money, if I can do it at all?

The vin number is: SAJGX5042XC034090

The odometer says about 150K, but the dealer replaced the engine under warranty at about 40K because the tensioners melted and there was the possibility that there could have been damage as I drove it about thirty miles to the dealership once I heard the strange noise coming from the engine compartment. So, the current engine may have about 110K on it. Unfortunately, I don’t know if the dealer put in a new engine or a second hand used, re-manufactured, or rebuilt engine. So, does the VN apply to the current engine?

I’m hoping that some of you nice forum members will be able to help me out with a solution to my dilemma. But please be gentle. This is my first time.


Thanks.





Jay
1999 XK8 Coupe

 

Going to the dealer is an expensive choice, not to mention that they often don't know what they're talking about when it comes to older models.

There is usually a number of used engines available with a 12 mo. warranty and it would be worth the time to do a google search.

 

Firstly, it would be better to remove the vehicle to a Jaguar specialist as they have a better understanding of the engine options available.

As RJ237 suggests, the least costly option may be to locate a used engine from a reputable source. If you find one, have the primary and secondary timing chains, tensioners and guides replaced prior to fitting it to the vehicle.

If you cannot locate a suitable engine, it may be easier to part the car out and find another X100.

 

Thanks, NBCat.

I'll certainly consider your suggestions. Unfortunately, there's no way I can easily determine whom to trust and who's engine is worth the effort. Ship it and then change the timing chanis, etc. Maybe plan D or E.

Jay
1999 XK8 Coupe

 

I may not have been clear enough in the wording of my question.

Certainly, I can take my car to a specialist but I still need to know which engine(s) can be used. And that's why 'm asking the question.

Can I use an EGR-equipped engine to replace my non-EGR-equipped engine. I need to find this out before I can look for, let alone buy, any replacement engine..

I will appreciate anything more you guys can do to get me closer to the answer.

Jay
1999 XK8 Coupe

 

As far as I am aware, the only differences between the engines would be that :
1. There's a different rhs exhaust manifold with a connection for the egr pipe
2. The throttle body will have the other end of the egr pipe rather than a blanking plate.
3. An EGR equipped engine will have a differently configured ECU but I have no idea whether that is "programmable" via dealer-level equipment, or whether the two ECUs would be physically different.
4. There are very slight differences to the cooling system as the EGR valve is connected to the coolant pipes at the throttle body.
5. There MAY be differences to the wiring loom - the EGR valve has a four-pin connector
which is not present in the non-egr set-up.

So ........... if you use your original exhaust manifold, original throttle body, original ECU, and original wiring I can't see why it shouldn't be OK. The two engines are, in terms of all the important bits, exactly the same as far as I know.


All that obviously assumes both engines are otherwise the same in terms of stuff like VVT solenoids, two or four pin coils, air-assisted or normal injection etc.

 

BobRoy has contacted me on the EGR question. The 4.0L SC engines have a EGR, but they have lower compression and can not be used. We don't think any normally aspirated north american 4.0 engines have a EGR, but the 4.2 does, and that would be a major project to use.

 

I suspect they are very few and far between, but an EGR valve was fitted to early n/a 4.0 AJ-V8 engines. I suspect you have been offered a s/c engine, but might be worth double-checking before rejecting it as unsuitable.
From the Technical Guide :


EGR was deleted on XK8 series vehicles from VIN 11462 and only used on XJR vehicles, North American specification 98 MY.

 

Add a can of Restore to the oil and see what takes place.

Gus
www.jagrepair.com

 

If ya got the money, switch over the to GM LSx swap.

 

Why don't you try to figure out what's wrong with your engine.

Is there water in your oil?
Is there oil in your water?
Is there white smoke(steam) coming from tail pipe.
Did you overheat the engine?
Is there any noise from the engine? (Knocking or ticking)
What cylinders have the low compression?
Are you getting any codes?

It maybe possible you only need new headgaskets. If it got overheated you may have dropped some valve seats. Depending on what's wrong it may be a lot cheaper to repair you engine than to buy a rebuilt.

There is a possibility of my selling you my 99XK8 engine that I already have out of the car. I was going to use it for a xj8 project but I will have to think about that one.

 

The VIN applies to the chassis, the engine has a separate number, which is basically a date/time stamp of manufacture. This number matters a lot.

I feel you need more data. The fact that the engine was possibly exchanged makes an analysis based on the VIN very unreliable. As you know, all the early engines had Nikasil lining. There is a very clear cut engine number (August 2000), and after that, Nikasil was abandoned. You need to locate the serial number of your current engine, and go from there. There is a great post here: nikasil-what-how-identify-faq-25912/

Have you made some effort to find out what is wrong with the current engine? Say, if this engine has Nikasil coating, the bores are reputedly VERY strong, and tolerance with the piston is tight. There is an off chance compression problems could be with just the rings. Alternatively, if the valves are leaking, having cylinder heads rebuilt has to be a ton easier/cheaper than finding a replacement engine. I believe the best way to determine if the leaks are with the rings or the valves is to compare a "wet" and a "dry" compression test. Some also do leak-down tests. I assume this is hard to do with the engine off the car. In addition, small cameras are now available for combustion chamber inspection through the spark plug hole. This might illuminate the condition of the cylinder bores and possibly valve seats, etc.

Quite frankly, now that the engine is off the car, it might not take too much effort to remove the cylinder heads and get a more complete analysis. I somehow have a hard time believing the engine is just done with so few miles.

One last thing, folks have mentioned several times that there are, in fact, 3 separate designs for the secondary chain tensioners. Is there an off chance you have the second design, still plastic, and you somehow have skipped a tooth, making your valve timing off? Removing the valve covers should tell you for sure, as the third generation design is all metal.

Just my thoughts, I hope this helps. Best of luck, and keep us posted.

 

+1

Fmertz it appears we both had the same thoughts at the same time

 

I suspect this is becoming off topic, but my XK8 VIN 04895 does not have a EGR valve. The top of the cat has a plate brazed on where the pipe would have been attached.

 

At the risk of staying off-topic - maybe it was removed.
This is my car (non-EGR)

 

RJ & David, I have several N/A cars from 97 to 2001. Only the 01 xjr has an EGR valve. All of the N/A cars don't have it. But all of their exhaust manifolds look like yours David. I guessing but I think they use the same casting for all the manifolds and drill it out when they need to install an EGR valve.

 

That makes sense. It's unlikely mine was modified because that would mean changing the intake manifold and ECU. It's more likely they used a exhaust manifold prepped for euro model and blanked it off.

 

It seems like the answer is NO.

My read of Jaguar's 1997 and later update technical manuals is:

None of the Normally Aspirated (NA) 4.0 engines have an EGR. The EGR was fitted to Supercharged (SC) engines as part of the 2000 Model Year (first year of the XKR?).

So, even if the EGR itself does not seem like much of a problem (it could be blocked off I suppose), what it seems is that you were offered a Supercharged engine, with the lower compression ratio, not really usable in an XK8.

Source: JagRepair.com - Jaguar Repair Information Resource, check the "XK8 Technical Guide" section.

 

See if this helps identify Nikasil

Link. http://www.jagrepair.com/NikasilEngineBlocks.htm

Gus
www.jagrepair.com

 

There's a risk of going entirely off-topic here, but :

From the technical guide (JJM 18 15 15/70 (August 1996.
Note the early vacuum controlled Cruise Control and Throttle Body - not applicable to the s/c engine as far as I'm aware.