Water in the oil 1989 XJ40.... ouch!

Well you just never know …

The one part of this project that I was dreading the most was removing the exhaust manifold from the head. I knew after 30 years it would be a battle. BUT MUCH to my surprise the two headers unbolted no problem whatsoever !!! The access to the bolts was excellent (except the bottom rear bolt, and that wasn’t that bad). So with the exhaust and intake manifold out of the way the next step is to unbolt and remove the head.

A gentleman in Ontario Canada has a clean milled 3.6L head with the valves all lapped and clearances set, ready to pop in. So I think I’m going to go that route. Now I just have to figure out how to get it here.

@Dick_Maury has a spiffy head shipping box: it may fit the head you have.

That’s great! Glad to hear it went smoothly. Sounds like you’re well on your way to having it all apart.

So far I’m a happy camper !

I removed all the head bolts quite easily. No drama and no corrosion. Knocked off for the night so the head’s ready to be lifted off in the morning and all shall be revealed. I’m hoping that the head gasket will explain to me why the water was mixing with the oil.

Believe it or not so far the whole project has been rather therapeutic. The big problem with this car is that if you need to remove 4 bolts, 3 of them are always readily accessible and the 4th is a nightmare.
But where would the fun be without a challenge.

Authors note … Being retired and having a very supportive wife makes ALL the difference :ring:

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A few question …

The Haynes manual says to remove the 2 cam shafts and sprockets BEFORE removing the head ? This isn’t necessary is it ?

Do I have to remove the distributor to make way for the chain tensioner ?

Do I just pull out the timing chain tensioner on the side of the head ?

Can someone please provide a little more detail on unbolting the cam sprockets and securing the timing chains.

Thanks so much. After all this work I don’t want to goon up something simple.

From memory the head bolts go through the camshaft caps? If so then its probably prudent to remove them, having said that I seem to recall that I had to set the valve clearances on the bench so the cams had to go in the head for that. My head hurts :frowning: (and I’m not doing the job)

Dennis When mine went it was between 5 and 6 it seems to be a weak spot.A new gasket and it was done . Mileage at the time was 185 km

It isn’t strictly necessary, but you run the risk of goinking an open valve. Just keep track of the buckets and shims.

Thanks guys …

Well I answered some of my own questions by bending my Jag guru’s ear and a little online research.

Mr Wiggles is absolutely correct. The cams do not need to be removed before you remove the head. As Robin pointed out since they have to be installed before the head goes back on it only makes sense that you can remove it that way. I agree that the Haynes manual is just trying to keep you from pulling the head and then setting it down the wrong way and possible bending some of the valves (i love people looking out for me).

It seems the only reason you have to remove the distributor is to make room to remove the timing chain tensioner.

I was told to place the #1 (front) piston at absolute TDC on the compression stroke and and undo the
4 bolts holding each cam sprocket. Then just zip tie the chain together so the head will lift up over it.

I removed the cowl and engine fan and with plenty of access I can rotate the engine by hand (plugs out). Now the easiest and best way to determine EXACT top dead center ?

Do you have the camshaft timing tool? That will give you TDC.

Grooveman - I am going to send you via PM a document I found tucked away in my Haynes manual from when I did the head on my car. Maybe it will be of some help - or not.

No I don’t have the cam alignment gauge. Is this where it would fit to show TDC ? I believe years ago Bryan had a detailed drawing of the gauge he made with all the measurements. Now if I can only find it.

IMG_0938%20copy

Thanks Mike for the great info and a super thank you for all the help you’ve given Joe on his no spark
problem. You certainly went above and beyond !!

Yes. Here’s mine. I bought it on eBay.

Here you are: http://www.jag-lovers.org/snaps/snap_view.php3?id=1086870471

The tool number is 18G 1433.

My modest contribution to the wonderful world of camshaft alignment tools.

A special nod to Bryan for his precise measurements, even if they were in metric … and really what’s that whole thing all about ?

So If I understand this correctly when my cool new tool fits in the cam notches that’s TDC on #1 piston compression stroke and I can safely undo the timing chain. Right ?

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At the risk of being labelled a Dougie Downer at best or an absolute moron at worst, here is my understanding: the camshaft alignment tool only ensures the camshafts are in the proper position for when (IF) the #1 piston is at top dead center. Now, if everything is currently in sync AND you use the tool to ensure the camshafts are in proper position (that is, the engine is rotated until both camshaft notches align with the tool) the #1 piston should be at TDC and, IF THE ENGINE IS NOT ROTATED WHILST THE TIMING CHAINS ARE DISCONNECTED FROM THE CAMSHAFTS ( SPROCKETS) everything should remain in sync when the camshafts are reinstalled with the notches aligned with the tool. Especially with the head off it is apparent when the #1 piston is at TDC. See the fifth picture here:
http://www.jag-lovers.org/snaps/snap_view.php3?id=1360620362

Dennis, when I replaced the head gasket on my car ( Sept. 2009) I used the TDC marking on the harmonic balancer to find the TDC after rotating the engine. I had 96000 miles on the clock at that time.

Mike, AKA Mr. “Dougie Downer” …

Your thoughts were my concerns exactly. Although I know that the cam shafts are in the TDC position because of the gauge fitting into the cam head slots … BUT … does this mean that the #1 piston was also at exactly TDC … hmmm ?

I’ll check the actual position of the #1 piston with a gauge screwed into the spark plug hole, but since the car was running perfectly I’m willing to take a leap of faith and assume that the piston position correctly corresponds with the cams.

Yep, get the three lined up and you’re good to go. When I did mine, I checked that I was at TDC via the spark plug hole and using the harmonic balancer. It never hurts to be too thorough with such an important step.