[v12-engine] Tappet Block Removal Questions (why can't we remove it?)

Hi all, slowly progressing through removing the B (left)
cylinder head from my son’s '89 XJ-S. At this point we have
successfully removed the camshaft and are trying to remove
the tappet block. First question, I can see only the 6
socket head screws and the 6 nuts below the block. We have
removed all of those but the tappet block seems still quite
firmly attached. This may be because of the large amounts
of black sealer used to glue it to the head (factory?), but
we have tapped on it as hard as we dare with various wood
blocks and hammers to no avail. It seems like there should
be more fasteners at the front end of the tappet block where
it goes around the timing chain, are we missing them?
Second question, do the studs for the cam bearing caps go
all the way through into the head? That is, do we have to
lift the tappet block over those studs as well (which might
explain why tapping it from the side doesn’t loosen it)?
The benefit of any experience would be appreciated!–
early '89 XJ-S
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In reply to a message from XJSdad sent Sun 1 Feb 2015:

Dear Anon,

You’ll find a row of allen key headed bolts running down the centre
of the tappet block in addition to the short studs you have already
identified.

The long studs holding the cam bearing caps and the four end ones
all go into the head, so the taappet block can only go up and down.
Even if you remove those studs, there are two locating dowels to
prevent you misaligning the tappet carrier from the head.

kind regards
Marek–
v12 E-type running MS3/3X sequential lpg and petrol
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

We have
removed all of those but the tappet block seems still quite
firmly attached. This may be because of the large amounts
of black sealer used to glue it to the head (factory?)

NOT factory! They used Hylomar, which is blue and prone to leaking.

– Kirbert

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !On 1 Feb 2015 at 6:54, XJSdad wrote:

Hi XJSdad,

There are 6 cap screws within the tappet block and 6 studs/nuts on the outer
side of the tappet block. There are also 4 long studs at the front of the
head around the timing chain that should be loose. Also each of the 14 cam
cap studs …

There are two dowels on the inside cap screw holes (front and rear) that
prevent misalignment. Ie it’ll only come up.

There is also a banjo bolt in the rear of the tappet block, that hopefully
you have found, that connects to the oil feed. You don’t want to put a crimp
in that oil pipe (don’t ask how I know :o)

ME

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

Excellent reason NOT to use silastic when assembling an engine …-----Original Message-----

We have
removed all of those but the tappet block seems still quite
firmly attached. This may be because of the large amounts
of black sealer used to glue it to the head (factory?)

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In reply to a message from Mark Eaton sent Sun 1 Feb 2015:

Yep…that’s an $80 and $155 mistake, depending what mood
the used part suppliers are in (don’t aske me how I know
either!)–
The original message included these comments:

There is also a banjo bolt in the rear of the tappet block, that hopefully
you have found, that connects to the oil feed. You don’t want to put a crimp
in that oil pipe (don’t ask how I know :o)


John. '95 XJS 6.0L convertible. Southlake, TX
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In reply to a message from XJSdad sent Sun 1 Feb 2015:

The OP is already aware of these oft mentioned fasteners.–
The original message included these comments:

the tappet block. First question, I can see only the 6
socket head screws and the 6 nuts below the block. We have
removed all of those but the tappet block seems still quite
firmly attached. This may be because of the large amounts


stephen davis 1976 XJ-S, 1989 XJR-S, Sl SWB XJ12 x 3
gorae, Australia
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In reply to a message from XJSdad sent Sun 1 Feb 2015:

All, thanks for the advice and suggestions, once I figured
out that the cam bearing cap studs and the cam cover studs
around the timing chain go through into the head we were
able to pop the tappet block off pretty easily. Thanks also
for the comments on the sealant. I am planning to use
Loctite 518 (applied sparingly) when we reassemble it, I’ve
had good luck with that in the past. Meanwhile, onwards to
removing the cylinder head! (more fun with that I’m sure…)
Thanks!
Gary–
The original message included these comments:

Hi all, slowly progressing through removing the B (left)
cylinder head from my son’s '89 XJ-S. At this point we have
successfully removed the camshaft and are trying to remove
the tappet block. First question, I can see only the 6


early '89 XJ-S
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In reply to a message from XJSdad sent Mon 2 Feb 2015:

I was at an engine shop recently and they switched from Loctite
5xx to Permatex ‘‘The Right Stuff’’ for their gasket maker. It is a
black elastomeric rubber compound and they claim they have had no
leaks, even on rough stamped parts like the oil pan on the V12.
It’s available in a variety of packages, and they use the short
cartridges in a caulking gun. The downside? Once used, it’s a
bear to disassemble the parts.

Sounds like that might have been used on your tappet blocks.

Rich–
76 XJ-S
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

I was at an engine shop recently and they switched from Loctite
5xx to Permatex ‘‘The Right Stuff’’ for their gasket maker. It is a
black elastomeric rubber compound and they claim they have had no
leaks, even on rough stamped parts like the oil pan on the V12.

I guess people want a “one-size-fits-all” approach to sealants, but
really you’d be better off getting the correct sealant for the job.
Loctite 518 – which is a Permatex product – is called for when
assembling parts with milled mating surfaces, such as the tappet
block to the head or the liners into the block. It’s no good for
stamped parts, though. The black rubbery stuff is what you need for
parts that don’t mate up all that closely, such as stamped oil pans.
Meanwhile, blue Hylomar makes an excellent gasket dressing (as
opposed to those other two being gasket substitutes) for paper
gaskets, while gortex gaskets should be assembled dry.

– Kirbert

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !On 19 Feb 2015 at 5:26, Rich Hedberg wrote:

Does anyone know the torque values for these fasteners? The nuts came off like nothing but the Allen head bolts had me worried they would break off before they came loose. Thank you.

I have used these values (from a service manual for 6.0 engine)
Tappet block to cylinder head (nut) 17-23Nm
Tappet block to cylinder head (socket screw) 22-28Nm
Tappet block to cylinder head (stud) 13-17Nm
Best Regards, Tom