TDi head gasket failed. Advice and opinions please

[chappers]

Hi everyone,

B5.5 2001 Passat 1.9 TDi PD100 AVB engine. JUST READ BOLD IF TOO MUCH TO READ

Head gasket failed almost 2 years ago. Coolant system was pressurising and spitting out all the coolant via the expansion tank overflow, and had no heating.

I replaced the gasket myself, but didn't get the head skimmed due to having read that the TDi heads shouldn't be resurfaced, and lack of time and money on my part. It didn't overheat while in my possession but the major symptoms appeared only months after buying the car, so may have already been slowly going.

The old gasket was damaged in the inner metal layers between cylinder 3 or 4 - can't recall which - and a coolant passageway.

Car was fine afterwards for over a year.

It has failed again and now the pressurisation is very high and the airlocks have reached the point of leaving me with no heating just before winter!

I would massively appreciate some advice/opinions on why it's failed again and what to do now, considering the age of the car.

Has it failed because I didn't get the head skimmed, or could it be because while doing the 2nd stage 90 degree angle-tightening, the 2nd to last head bolt on the right rear of the head suddenly became easier to turn before reaching the 90 degree point?

I'm assuming it either started stripping threads in the block, or the bolt went beyond yield point. Could the threads have already been damaged and that's why the gasket failed the third time? I torqued the head bolts to the correct torque and angle tightened as per instructions (stage 1 - 90 degrees, stage 2 - 90 degrees).

Could that bolt have been applying too little force and so the gasket has failed as before, or is it more likely there is a dip in the head between cylinder and coolant passageway and it's slowly failed over time.

My other question regards resurfacing. It's an old car, I'm in a full-time poverty pay job so will have to borrow money to do the head gasket and must keep costs low. Can't afford another car. Should I just replace gasket and if bolt goes slack again while tightening, assume block thread is damaged and see if a garage will call out to m y house and cheaply install a threaded liner (timesert is it, or something?)?

Or should I get head skimmed, and hope that the valves now protruding out further don't hit pistons while using original 1-hole gasket thickness?

Or should I get it skimmed, use a 2- or 3-hole gasket and hope the extra combustion volume doesn't cause trouble or blow into the gasket wall that would not normally be so exposed?

Or should I sell all my possessions and get the head skimmed, valves sunk in deeper by the same amount taken off the head, and valve stems ground down by the same amount and use the original 1-hole thickness gasket? And then hope to the big man in the sky that the head bolt (or any others) don't get easier to turn suddenly during angle-tightening, which might mean having to buy 10 new head bolts and getting an insert put into the block.

I'm stressed about this as I live in the sticks and cannot do without a car and have no savings or spare cash. What to do?!