Pajero Owners Club of South Africa

I was sorting all the head bolts and test fitting them, and two of them only went half a turn in and jammed... #$%$#...

Pulled the head off and had a closer look. Two of the head bolts that go through a tubular bush that centers the head over the block, the top 4mm of the threads were very slightly damaged; enough to jam the bolt from turning - seems as if someone at the engineering shop had poked something in there they should not have.
At this stage I was really chewing a wasp, some choice words spoken too that even my dogs were looking at me funnily!

The head bolts are M12x1.25 - a very fine pitch. I only have a M12x1.75 & M12x1.5 tap, so I had to wait until Thursday morning to speak to the engineering shop who did the work, & they said they would loan me the correct size Tap to clean the threads up.

I picked the tap up on Thursday morning, and started to prepare to clean the threads up that evening after work. I covered the entire top of the block with duct tape and taped a plastic bag over the timing chain assembly - I don't want and steel filings in the engine.
I then proceeded to clean the treads out, I did not want to 'cross-thread' any of the existing threads in the hole so I had to make sure I was square & true when installing/cutting with the tap - see spirit level to help me check.


I then cleaned the thread out and installed the bolts to check for fit - perfect! I then blew all the debris off the engine and removed the protective duct tape & plastic bag. I also re-cleaned the top of the block with acetone to remove any sticky residue of the tape left behind.

If ever the car-gods consider to reward diligent effort with a smooth running engine, then this is the one.

I then proceeded to fit the head - head gasket on and head on. Sorted all the head bit & bolts out on the work table. The Manual state all bolts and bolt seat are to be lubricated with oil prior to torquing down of head - DELO400 doing it job here: There are 5(6) steps to torquing head down:
1. Tighten bolts in sequence to 98Nm (1-18)
2. Loosen all bolts in reverse sequence (18-1)
3. Tighten again in sequence to 48Nm (1-18)
4. 90 degrees in sequence (1-18)
5. A further 90 degrees in sequence (1-18)
6. last two bolts over timing case to 57Nm (I found this to be WAY too tight for the threads in top of aluminium timing case, I reduced it to about 45Nm).

First torqe of bolts So I don't get lost in the 90 torquing steps on the head, my check/tick sheet for of the 5 steps on the bolts (1-18).

Though I would show my "Work-station"

It is a 1.2 x 1.2m stainless steel table on castor wheels (for it to move around), I also bolted an old monitor to the top on a swivel bolt, and hooked it up to an old laptop with all the photos of the tear down and workshop manuals on it too for quick reference. I can easily move it around the engine stand which is also on castor wheels.

Very very nice.

Remember to have the crank and camshaft at TDC before you tighten the cam caps. You dont want to press a valve into a cylinder. Easy mistake to make than can bend a cam and cost you an engine.

PS : The top timing chain tensioner bolts are specced at 33NM - that is also too much for the soft head I have found. Use about 25NM but use your hands for "feel"

Had my heart stop there for a second when you said you found a problem!!

Well done for sorting it out properly and not just forcing it through!

Love the work-bench-station!

CATS

Two heads...
V8 DiD.
I want one

Hi Nick
Your on fire ! Excellent job with great info and pics. I commend you and your attention to detail. Can't wait to see the end result and start up.
Bernard

OK More feedback.

After fitting the head I had to install the rockers and cam-shafts.
Measuring cam-shaft profiles. Cam shafts installed. Sprockets on - note the bolts have reverse threads. After the cams I had to fit the injectors with new nozzle & leak-off rail gaskets. See dust caps I got from CL diesel (for free) after the duel stage pop testing. You have to stick the injector tip nozzle gaskets on with copper compound as they only expand and seat once the injectors are torqued down to 20Nm.