(T) punto cylinder head tale

hi folks

been looking at this great site for some time now and have just changed the head gasket on my son's punto 60s which he's had for 6 months.

It started to boil over when stopping after a run, needing a top up and a bleed, so looking thro the forum and hoping it wasn't the gasket, i changed the water pump on which the bearing was found to have gone letting a trickle of water past the seal. Well, while i could get to it i checked the core plug nearby which looked rusty. i prodded it with a screwdriver and it went straight through, it must have been leaking as well. Oh great, i thought, that's all it was. changed the core plug (£1) and while i was at it i changed the timing belt and tensioner as advised in the forum. It started up ok and was running quieter due to the new tensioner. i was well pleased.

Next day my son tells me it's boiling over again, oh drat! what can it be now? engine running ok, no water or steam coming out of the exhaust, no mayonaise in the oil filler cap and no oil in the water as far as i could tell.
i removed the thermostat and fitted a bypass swith to the electric fan so he could have it running all the time. Then i flushed the engine and radiator (seperately so one didn't contaminate the other -loads of cr*p came out)
No joy though, it still boiled over.

Ok i give up. time to change the gasket then.

Got a head gasket set (£18) included a rocker gasket and a camshaft oil seal.

Followin the manual, everything went fine until i came to unscrew the head bolts. One of them rounded off!! man they were tight! Mind you i was using a cheapo 13mm socket, so popped into town and got a proper decent 6 sided long professional socket from Halfords (£4.50)

Just before i got back to work on it, my neighbour appeared and saw what had happened. He then disappeared and came back with a special extractor which he promised would get the offending bolt out. This was a hardened socket with a left hand spiral thread inside, a bit like the opposite of the more familiar stud extractor which i had used in the past.

Glad to say, it worked a treat, although it wouldn't have fitted on the front middle bolt as i had to remove the cap off the centre camshaft bearing just to get my halfords socket on, so whatever you do don't ever round that one off!!

Well, off with the head. what a sight!! the water holes in the head and the block were all crudded up. there could have hardly been any cirulation. There was a slight split in the gasket from a waterway to the back of the head which i reckon was where the leak was. (couldn't see the leak with the engine running tho'.) I think it was the original gasket it had "alto" (top) stamped on it.- the new one was a pattern gasket.

it took me a day to clean everything off, i had to use a small drill bit to get the crud out of the holes. This was brown like rust and very hard. There was also some aluminium oxide present which reinforces the advice of one of the posters on the forum to make sure that 50% antifreeze mix is always used as it has a corrosion inhibiter.

i was lucky that the head face was still flat, i checked this with a straight edge and feeler gauge.

i cleaned the rest of the engine down with gunk followed by steam cleaning which i found really effective.

Assembly time.- made sure the bolt holes were cleaned out and the head and block faces were grease free (cleaned with petrol) clean the head bolt threads and very lightly oiled them. (yes i used the original bolts, although the are stretch bolts i reasoned that they were designed to be used within their elastic limits -hooke's law or summat-so they should be ok.)
dont use too much oil on them or when you screw them in the oil comes up the threads and gets on the head and block faces which needs to be grease free.

i torqued the bolts down in the correct order
stage 1: 22 foot punds,
stage 2: tighten thro another 90 degrees (phew that seemed tight)
stage 3: ANOTHER 90 DEGREES (I THOUGHT THE BOLTS WOULD SNAP - but they didn't. thank you God.

i wonder if, even a head was warped, whether it would flatten back out under this kind of pressure

Anyhow the rest went together no problems and after a week, so far so good.

And it didn't cost too much.

As soon as i get chance, now i know it's ok and no leaks i intend to drain the water out and give it a final flush to get any more loose cr*p out, replace the thermostat and refill with the correct antifreeze mix to keep it sweet.

Any more problems i'll keep you posted.

For the sake of 5 or 6 quid i would pop into Halfords and get their two part coolant flush stuff and just follow the instructions. You would be amazed at how much extra crap comes out. At the time my head gasket 'blew' i also bought a new Thermostat/housing. When i flushed the engine i did it with the old Thermostat housing fitted, but with the actual element removed. This aided the flow of water through the engine/radiator and also makes it much easiers to flush the engine block with a hose pipe.

I note you didn't say you got your head skimmed, i thought this was a worthwhile 'risk of failure reducer' for the £35 it cost me, sounds like you've been fortunate though.

great idea, thanks. i'll do that.
yep, you're right about the head skim, i took the chance to save time and furthur dismantling but if it had been obviously warped then would definately had it done.

cheers

hehe, i also hate that 2nd turn through 90 degrees :? never seen one snap tho but i still hate it.

yeh mate, made me sweat a bit. but don't you think that that amount of tighening would pull a (not too) warped head down? i mean, how stiff is an aluminium head? just a thought.

I had to close my eyes the creek . but the car now done 70 k on new HG . punto 55s got 99k on clocks and still goes well
Richie