Suspected head gasket failure

[disco stu]

Yes, just don't tighten down the rocker gear until it's all lined up and timing belt is on. You also don't want to be opening valves without the positions moving (and timed correctly) in case of valve contact with the piston. Not sure if that is possible with your engine, but it's good practice just in case

[pharb]

Yes, just don't tighten down the rocker gear until it's all lined up and timing belt is on. You also don't want to be opening valves without the positions moving (and timed correctly) in case of valve contact with the piston. Not sure if that is possible with your engine, but it's good practice just in case

Valves are dead vertical so you won't be able to bend if younwind over by hand and hit piston, but heaps easier to set valve clearances on bench before fitting head.

And don't forget to reset chain tensioner before you finish!!!!!

[Tomalophicon]

Thanks everyone, this is helpful.

I have the fan and shroud off, tappet cover and glowplugs removed (all tested DEAD).
I inadvertently turned the motor anti-clockwise a tiny bit undoing the fan - removed the tensioner and re-tensioned though before rotating it correctly to find TDC.
Both valves on 1 are closed and valves on 4 are just closing/just opening! There is a mark on the crank pulley that lines up with the 0 on the mark that looks like this: |||0|||||10 and two dots are lined up in the top/middle of the cam pulley. I'm assuming this is correct.

I'll press on and report back - hopefully with some more positive news!

tom.

[disco stu]

Yep, you sound all set Tom.

Interested what makes valve clearances so difficult on these that you're best doing it on the bench. Last car I did valve clearances on was a gen 1 petrol pajero about 15 yrs ago though, so I'm fairly out of touch. I just hate trying to rotate the camshaft to line things up when the valve springs put pressure and it keeps trying to rotate etc

[Tomalophicon]

Yep, you sound all set Tom.

Interested what makes valve clearances so difficult on these that you're best doing it on the bench. Last car I did valve clearances on was a gen 1 petrol pajero about 15 yrs ago though, so I'm fairly out of touch. I just hate trying to rotate the camshaft to line things up when the valve springs put pressure and it keeps trying to rotate etc

I've not done them on these. Only on older land rover and Alfa Romeo engines. These require shims i believe.
I'm sure an assembled head will come with the valve clearances set but double checking will be a good idea.

[pharb]

Yep, you sound all set Tom.

Interested what makes valve clearances so difficult on these that you're best doing it on the bench. Last car I did valve clearances on was a gen 1 petrol pajero about 15 yrs ago though, so I'm fairly out of touch. I just hate trying to rotate the camshaft to line things up when the valve springs put pressure and it keeps trying to rotate etc

Shim adjustment.

Have to check clearance with camshaft in place, but need a special tool to depress valve without moving camshaft, or alternatively remove camshaft to remove shims, then measure shims, calculate change in shim thickness to correct the clearance, then get appropriate shims and fit, then refit camshaft.

Lots easier to do on the bench than leaning into the engine bay and also mucking around with cam sprockets, chains and tensioners etc.

[disco stu]

Bleugh!! Fair enough, sounds like a fair bit more of ordeal than those that I've done-they were just screw down to the right point and tighten up the lock nut

Can you loosen/remove rocker gear once you have the shims installed at correct height etc? I'm just thinking of the possibility that the rocker gear might be in the way of head bolts

[pharb]

Bleugh!! Fair enough, sounds like a fair bit more of ordeal than those that I've done-they were just screw down to the right point and tighten up the lock nut

Can you loosen/remove rocker gear once you have the shims installed at correct height etc? I'm just thinking of the possibility that the rocker gear might be in the way of head bolts

No rocker gear. Cam lobe acts direct on shim/bucket/valve assembly.

[disco stu]

Sounds a bit easier

[Tomalophicon]

Hi guys,
Appreciating all the information so far.

The head bolts are all out. Is it correct that the two smaller bolts have no washers, unlike the big 12 point bolts?

The bolts have been punched only once, is it better to use them again or get a new set? Manual recommends factory bolts can be used thrice in total.

Thanks

Tom.

[disco stu]

Are the small bolts right at the front of the timing cover? I haven't had one of these apart, but that's normally where you see the smaller bolts. Just check the torque on them in the manual, if it's not too high they should be alright

[Tomalophicon]

Are the small bolts right at the front of the timing cover? I haven't had one of these apart, but that's normally where you see the smaller bolts. Just check the torque on them in the manual, if it's not too high they should be alright

Yes that's right. The two front corners.
Ok cheers for that mate.

[disco stu]

I'm guessing it's not even head gasket material under it, possibly even just sealant.

I'm let someone else answer the reusing bolts question. I have had Ford ones break on removing, repeatedly, causing no end of problems

[pharb]

From memory (nearly 20 years since I had one apart) the bolts are "stretch to yield" which means you do them up to a specified tension, then progressively turn them another set angle such as 90 degrees, then another 90 degrees etc.

These type of bolts are generally used only once.

I have learnt that there are quite a number of mechanical items you can take short cuts (ie some engines I regularly reuse rocker cover gaskets when others say they are once only), however head bolts I have always folowed the recommendations.

[Tomalophicon]

No prob replacing them.

The head is off thanks to the assistance of you fine gents. I have cable tied the timing chain around the gear and squeezed another around it and it's not gonna move.

There are no obvious defects in the head gasket though this is the first one I've removed so have nothing to compare. It's a 4 notch. I will be ordering a gasket on Monday in case there's a long back order time.

I will be calling head shops on Monday to see what's possible with a refurb. The pre-combustion chambers are ceramic so I assume the head is genuine.

I have ordered an EGT gauge.

I will be taking the injectors in to get a service ASAP.

I will flush the radiator and replace the radiator cap and the thermostat.

You can see the gross copper sealant I used when the trouble started - but it did get me and the family home.

I will add updates as I go along.

Thanks again,

Tom.