Hey Guys,

I had the XJR out yesterday and was WOT when I heard a puff followed by a bad shudder. I pulled over immediately. Prelim diag shows that one whole bank is not working. The mechanic just called and said it may be a blown head gasket but he is not sure. He will be going in further tomorrow.

I thought when you blow a head gasket there is a lot of smoke and coolant? There was none and the car was able to move around at a very low speed in limp mode.

Car has 68k miles.

Anyone ever experienced anything similar to this?

 

Head gaskets can fail in a number of places, and supercharged cars with their higher combustion chamber pressures will always test a gasket fully. Hav ing said that, I would not expect all four cylinders of a bank to be affected, only one or two. If blown between two bores obviously two cylinders are affected. For all four it would have to be a mega-failure !

Only if gasket blows between chamber and a coolant passage will you get coolant vapour and pressurisation of the coolant passages.

A compression test should throw some light on things. Lets hope it is not too bad. You could have holed one or two pistons, of course if you were really tramping it, (which I assume WOT means).

 

Wow, that sounds spot on. I stopped by and the mechanic said the same thing. That basically it wouldn't necessarily blow smoke or have oil in the radiator. As of right now he said there is no compression in 2 cylinders of bank 1. He will be opening it further tomorrow.

What do you mean by holed the pistons?

Yup. I was giving her the beans and she was in sport mode. Which really feels like full on attack bc the car refuses to downshift. It feel like that sport mode would work well on a race track, but for spirited freeway driving it seems much too aggressive.

And thanks for the valuable input!

 

WOT = Wide Open Throttle

 

The only time I was told that I had blown a head gasket it turned out to be a hose! It wasn't a Jag. Most people fear a blown head gasket -- it can be a very expensive repair, too so the mechanics like it as well.

Keep probing, the correct problem will show it's ugly face soon and then you can solve the correct problem. Good luck.

 

If those are adjacent cylinders, it looks at first glance to have blown between the bores. Obviously a big nuisance, but not too difficult or costly to put right. If they are not adjacent, you have either bent one or two valves, or holed a piston or two.

All will be revealed when the head is lifted. Get your wallet ready !

 

WOW. Im scared. Hopefully my 3rd party extended warranty company steps up to the plate.

The mechanic told me $1500 just for teardown labor. Does this sound correct?

Does any body have AllData or any labor time resource to confirm that it takes 15 hours to pull it all apart? Sounds a little ridiculous to me.

 

It would have been better to know the hours he wants, as labour rates do vary. However, as your's is an XJR, and thus supercharged, there will be an awful lot of stuff to clear out of the way before the head can be lifted off. The supercharger and its gubbins sits in the V on top of the engine.

Anyway, lets assume a UK rate of £55 an hour, (my local independent), which is $88. Divide 88 into 1500 and we get 17 hours, which does sound a lot for just a teardown to allow work to start on the head etc, but OK for the whole job, I would have thought.

Anybody else care to do the arithmetic who know US labour rates ?

 

I got 3 quote a year ago all in the neighborhood of 1800 for one bank - full job (indy). This was a XJ8 so a little more for XJR - in my case it fortunately turned out not to be related to the head gasket but was a oil cap the shop never put back on so I lucked out.The head gasket is not prone to failure on these car and neither is a hole in the piston - all statements per my dealer.

 

I do not feel as of the mechanic is trying to take me for a ride, however I do not know him that we'll. Supposively will not have true answers until the head comes back from the machine shop next week.

 

So the verdict is in. I need a motor. Rod bearing came apart... tore everything up.

Does anybody on this forum know what the correct labor time for removal and re-installation of this motor is?

 

If I were you I would ask Jaguar USA if they can help you on this - such failure is unacceptable and should be that to Jaguar as well. The engine for my XJ8 was 10k - this was a rebuild with 36k miles of warranty.
Like intimated above by car started to smoke badly little more than a year ago it was 4.5year old and had 60k miles on it. I took it to a indy shop - they first thought the car had a blown head gasket but later revised the diagnosis to a hole in the piston because my car was smoking and burning oil. I contacted Jag USA and was treated good and they insisted that I would get the car to a Jag dealer ASAP. The dealer determined that this was because the oil cap had not been put on from the oil change 2 days ago (indy could confirm that cap was off when they got the car) and replaced spark plugs and cleaned up the inside - fixed, but I always had the feeling Jag USA was looking at this seriously and was considering to help - never got the run around - very impressed. I never believed the indy shop intended to scam me they paid for all expenses related to the misdiagnosis afterwards no question asked - it was just a misdiagnosis.

 

Thanks for that. I will definitely use your advice and call them today.

 

So it threw a conrod as we say in the UK. Did it come through the side of the block ? Engine wrecked so another one is needed.

 

I understand that this sort of thing can and does happen but this is (so far as I'm aware) the first time I've seen a report of a blown 4.2 engine. I usually hang out on the XK and XJ 350 Forums for the past 3 years so my insight is limited but my impression is that blown up engines are rare.

What say you gentleman?

 

I agree, it's very rare for modern engines to throw rods. Quite common with cars that once had aluminium conrods though. My Triumph 750 triple I owned in the 70s had aluminium conrods, but they were very robust for their size and quite short being a small engine. I used to rev this engine over 8000 revs.

The only one I have actually seen through a block was a Rover 75 1.8 litre. This was caused by the owner driving fast through a flood and hydraulically locking one cylinder. This bent a conrod, which then made a noise banging against the side of the cylinder, but owner ignored it because "the noise went away after a while". Sure it did, because it eventually knocked a piece out of the cylinder liner !! A week later - BANG !!!

A gentleman called Ron Mundy who had been a Jaguar development engineer, told a story of a standard XK 4.2 engine on the test bed in the 60s throwing a rod through the side whilst he and a colleague were inspecting it. The rod nicked his colleague's hand slightly as it passed out and away at high speed. He had been scratching his ear at the time !!

 

Hello All,

I just wanted to go ahead and share what transpired after I left off with my 04 XJR needing a motor. After 2 weeks of dealing with the people at Jaguar USA, they came back and said they were unwilling to offer any assistance to me whatsoever on account of my vehicle not having proper service history (complete BS, because I sent them everything from Day 1). I am completely disappointed in the brand, and sad that Jaguar clearly does not care about the retention of its clients. I really did want to be the guy to choose a Jag over a Benz, but now that I got all of the "I told you so's" from my family, and friends... I'll probably not be coming back to Jaguar ever. Unfortunate really, its a beautiful car, but more than the $10,000.00 its going to cost me to fix the car, I am saddened that the brand basically told me to **** off.

Shame on your Jaguar.

Take a look at the pics of the damage to engine, and the letter they sent me after wasting my time on account of them taking their jolly old sweet time to get back to me. Its pathetic really how they handled it.

 

Those are some sad looking pictures!
You might want to edit the attachment to remove your address.
What do you think MB would have done with a similar situation with a car 4 years out of warranty?

 

Really???? While the 4.2 is a reliable engine and we seldom see failures like this. Your car is 8 yrs old. Its not a hyundai with a 10/100 and i dont of any manufacturer that would step up on a 8yr old car. Jaguar has one of the longest luxury car warranty periods. But at some point in time you have to say this is it and draw a line in the sand. Otherwise they could have a lifetime warranty till it hits the junkyard. Can you imagine the costs built into the car new to cover this? Want mercedes? Ive got frineds that are techs on them and they constantly complain about all the heavy line repairs they do(engines)its a luck of the draw. You never here about anyone complaining about this model on here unless its air springs, occassional trans shifting or t stat housing cracks. Knowing what i know about the model. Ide buy and own one in a heartbeat and it will be my next jaguar and specificly an r too. I just drove one yesturday down the freeway and reset the mpg trip computer. Hit 35mpg. You tell me another large luxury car that will do that!!!
Go buy a $4k lkq engine and installation for $2k and youre back in business for $6k. To test for a blown head gasket they could have done a block check in the cooling system for presence of exhuast gas, and a leak down test. That would have been the definitive, you can pull spark plugs and go in with a bore scope to look in the cylinders. Theres no reason to do full tear downs unless you just want to guarantee youre gonna get alot of money. Once torn down its hard to not go all the way or take it from that shop and they know it. Thats why they do it. And what happened to your 3rd party warranty????? Where are they???

 

True words and good question, unless the motor exceeds the value of the car even the most basic extended warranties at least cover motor replacement...

Don't give up!