DIY: Cylinder Head Replacement & other items

[macjohnw]

I recently did the following on my Pajero, after blowing a head gasket due to a blocked radiator @ 520,000km. After struggling to get a decent local mechanic willing to do the work, I decided to just do it myself. Transporting the car to MitsiTech would have been to expensive. Thus I did the following:

- Replace head (new AMC head & bolts)
- New head gasket and others (Victor Reinz)
- Install brand new radiator
- Flush/clean/pressure test the condenser, intercooler (gearbox oil cooler in process)
- Repair leaking power steering pump
- Replace waterpump (AMC)
- Replace thermostat
- Replace oil pressure switch (started leaking two days after the engine was assembled)
- Flush & refill ATF + replace gearbox filter (Mitsu ATF)
- Replace radiator cap
- Drain and fill 2 x diff's oil
- Drain and fill transfer case oil
- Drain and fill engine oil + filter
- Replace fuel filter
- Flush and fill cooling system (Mitsu coolant)
- Remove and block EGR valve and piping
- Tested injectors

I will post a summary of the parts, services and other costs in a while.

[macjohnw]

TIPS:

* Wash the motor and engine bay before you strip, if possible - it helps to prevent dirt getting in where it should nto be. I could not beforehand.
* Take PLENTY of pics as you strip. You will forget where and how everything belongs. It helps tremendously when assembling again. I just about took pics before and after stripping each component. Also take pics form different angles/views.
* Buy about 40 ziplock sandwich bags - use it to bag and label the bolts/parts as you take them off. Get a permanent maker pen and write on each bag a clear description. Stack the bags in the same order as the order in which you stripped - it gives you a very good idea in which order to reassemble. Get a box/container and stack them in there.
* Mark the injectors 1 to 4 and replace in the same position when assembling. The same goes for the injector pipes - it helps to show which goes where. ( I used some blue masking tape to label parts that dont fit in the ziplocks). I tried to replace each important item in the exact same place where it came from.
* Plug holes/openings with cloth or plastic bags - turbo/inter-cooler openings etc.
* Mark the banjo bolts properly - on the turbo the water and oil banjos look the same, but they have different internal flow hole sizes


This is one of the videos I watched to see if there are small quirky things to keep in mind when replacing the head, it gives a nice basic guideline:

https://www.youtube.com/watch?v=SNJsT4LlYgM


Mainly I stripped the parts as follows:

1 - Belly plates and exhaust front pipe.
2 - Drain coolant and oil
3 - Right (airbox, turbo pipes, manifold, egr pipes etc)
4 - Front (fan, radiator, condenser, water pipes etc)
5 - Left (battery, fuel filter, intake manifold, covers)

[macjohnw]

Here is a summary of the costs. Note that I did do a few extras or bought some tools, which increased the amount a bit.

I managed to get all the major and important parts from Alert Engine Parts and Mitsu.

The camshafts, valves, valve springs, injectors were still good and it was not needed to repair them or purchase new ones.

[macjohnw]

The trickiest/riskiest part was to keep tension on the timing chain when removing the cam shafts and subsequently the head itself. The video gives a good idea how to do this. I just added an extra step by using a Rox strap and rope, then tied it to the bonnet latch. Also secure the rod that keeps the bonnet open with a rope - you dont want that thing slipping and then cause the loss of tension on the timing chain.

Best to mark the pulleys' position on the chain before loosening anything - in case they also slip or move. Then fasten them with cable-ties together.

If the chain becomes slack, it could jump some teeth and that is a whole bunch of extra work which you dont really want to do. So, be very careful when doing it.

NOTE: Stuff paper or towels into the timing chain cavity to prevent items falling down into the motor.

[macjohnw]

EGR piping and valve items removed.

[macjohnw]

Old waterpump 520,000km VS new one (Alert Engine Parts).

[macjohnw]

When removing the fuel filter - drain it by placing a container underneath as you unscrew everything. It is not good for your starter when pouring diesel all over it like that. I had to replace one or two starters because of this previously.

Also remember to plug those lines.

[macjohnw]

PS:

Another thing to remember - do not rotate the crank anti-clockwise as it could cause damage to the timing chain and tensioner. You will have to rotate it in order to get the marks on the camshafts aligned towards the top, or to give the timing chain a little slack when removing the guides/pulleys etc. Always clockwise.

[OnDerbroek]

Subscribing

[JonnyD]

Tested radiator fluid on my Paj and it seems that I have a blown head gasket or worse....

How can one know if it is only the gasket or if the head is gone as well?