Assembly is reverse of removal

Well, the head is back from the shop and it looks fantastic. Turns nicely and all lined up.

Now we have turned a corner and start putting it back together.
What are the opinions on how much to put back on the block before dropping the engine back in the bay?
Obviously at the beginning I had removed the head first without removing the intake entirely. When it became apparent the engine needed to come out, I stripped it down almost completely before lifting.
Now… part of me wants to put as much of it back together while I have easy access, including putting the head on and much of the plumbing under the intake. Exhaust side I can wait on.
This creates some issues for lifting points (I have lift straps tho) and the potential to get a sequence of assembly wrong and not be able to access it.
If I lift it back in naked and reinstall intake and exhaust goodies from the bottom up - I think I can sequence better. But then I’m hunched over the bay for days.

What say you?

Jeff …

It’s always a great feeling when you stop taking things apart and start putting them back together.

** WARNING ** Remember the exhaust and intake valves are interference (they live in the same space at different times). So be careful when you’re rotating the exhaust and intake cams to line up the alignment notches.

I would definitely build up as much of the engine as possible before you install it. That includes all the hoses you can, the starter, the power steering and water pumps, the intake and exhaust manifolds. I think you could probably also install the alternator and a/c compressor. Why not make it easy on yourself while you have full access. If something gets in the way you can easily remove it.

I’m sure it will be a bit of a hybrid. I want to be able to easily get to things like the grounding straps and the oil cooler line etc. I’m just worried I’ll get something out of sequence, mostly under the intake.

Jeff …

You might want to consider eliminating the whole oil cooler system which would include the two hoses, brackets, and cooler radiator. the hoses are prone to leaking later in their lives and removing them from the cooler radiator can be almost impossible as they weld themselves on.

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Jaguar decided that they didn’t really need the system so on later XJ40s they designed a rather elegant bypass. I did the conversion on my '89 many years ago and have had no problems even during our Texas summer heat.
1988-1997 Jaguar XJ6 Oil Cooler Housing - Engine Mechanical - MTC 88-97 XJ6 Oil Cooler Housing - 592-01004409 - PartsGeek
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When I did mine I just removed the cooler section from the filter head and used shorter bolts, the other advantage is that there isn’t the <> 1 litre of dirty oil that you can never get out of the system that immediately contaminates the clean oil.

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Oh, that’s nice and unexpected. It’s on order!

I would recommend having the engine completely assembled including almost all the bolt-ons. That’s how I dropped mine in and it wasn’t too difficult.

I used a strap to lift my engine and transmission assembly. The intake actually works quite well for it. I believe there’s a pic of me dropping mine into my car in the JL photos section.

Jeff …

If you ordered the bypass from Parts Geek did you note that you also need the two sleeve adapters and O rings ?

I didn’t see that, no… grrr…

This sounds appealing instead of the bypass - I can just shorten the 4 bolts. Doesn’t create any clearance issues does it?

I’m going this route…cancelling bypass and going to grind the bolts down.

Jeff, yes, you can use shorter bolts and then you do not need to buy the bybass kit. Last summer, I removed the oil cooler and used shorter bolts successfully.

Jeff …

If memory serves me (and why would it) many years ago this issue came up. I believe it was pointed out that because of the internal baffle design of the oil filter to block housing, eliminating it changes the flow of the oil to the filter. I wouldn’t swear to it in court but I think Bryan brought it to our attention and that’s why I didn’t do it. If it was that simple why did Jaguar spend the money to come up with the bypass ?

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I believe we could start a entirely new forum called “Why Did Jaguar?”

I’d say it would be easier from a service perspective to install the bypass (esp if the seals were leaking anyway) than to remove the four mounting bolts?
I guess since others have tried eliminating it - with success - I’m willing to try it rather than wait to source those parts. :man_shrugging: I’ll give it a closer look this weekend.
I’m already discovering that having a second engine gives me parts options! So if I have any issues, I can always go the other route.

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My cooler on the old engine was leaking at the seals, I’ll just replace the seals which I’d have to have to do anyway for the bypass. If it leaks again, i’ll consider collecting everything for the bypass…

Jeff …

Just thinking of ways to “Future Proof” your engine :smiley:

In 2008 Bryan wrote: ”Don’t go to the trouble and expense of ordering the oil
cooler by-pass parts used by Jaguar on later models which
did not have an oil cooler requirement, but do what is
actually recommended in the Jaguar factory service manual -
i.e throw away the oil cooler adaptor and bolt the filter
head directly to the block. Of course you need shorter
bolts, but buying those must be a darn site cheaper than
ordering the by-pass bits from Jaguar which would cost over
45 quid.”

Otto …

Excellent find ! I searched all over for Bryan’s feedback on that and couldn’t come up with it.

So obviously my memory was 180 degrees out. But why then didn’t I do that at the time instead of using the bypass pipe ??? Finding shorter bolts certainly wouldn’t have been a problem.

Yes, the bolts are easy to find. If I remember right, the bolts are M8 x 50 mm.

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The more I look at it though

  1. it seems like the “direct bolt” option is a way to avoid installing the bypass, and the hassle and expensive of sourcing these parts. I’m down with that.
  2. but the flow of oil with the cooler installed seems to go: from the block, into the cooler fixture, out to the cooler, returns cooled oil back into the fixture, where it enters the filter outside ring, filters the oil and returns it back through the big hole. Do I have that right?
  3. Does removing the cooler line fixture and bolting the filter fixture directly mean that oil doesn’t flow correctly? I suppose I’d have to look at the fixtures seperated to see but does this arrangement just dump the oil in the same place as it it picks it up?

I’m in a pickle. I have two coolers (Engine One and Engine Two provide me with duplicate parts) I received the bypass yesterday, but can’t find the two adapters need and don’t have cooler oil rings either.
The simplest thing to do would be to replace the cooler oil rings.
The least leaky thing to do would be direct bolt.
The longest thing to do it keep searching for the adapters needed.

Jeff …

Because of the age of the car there is an excellent chance the oil cooler hoses or the cooling matrix itself will start leaking at some time in the future. So I think it’s a no brainer to get rid of the entire unnecessary oil cooling system unless you spend your summer vacation at Death Valley Cal (the hottest temps on earth).

I still have lingering memories of discussions we had about the effects of the oil circulation with the direct bolt on vs the bypass adapter so it was a recognized issue.

Can you return the bypass you purchased and order another one that includes the sleeves and O rings ?