Vauxhall Astra 1.8 petrol - Piston replacement

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Mon 12 Jun 2017 10:38
Vauxhall Astra 1.8 petrol - Piston replacement - strickjumpers

Can anyone tell me if the sump is easily removable to allow big end cap to be taken off so I can draw the piston out, it was damaged by the broken spark plug. don't yet know if the bore is scored, don't know if it's financially feasible for 53 model even doing the job myself. thanks, Mike

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Mon 12 Jun 2017 12:20
Vauxhall Astra 1.8 petrol - Piston replacement - elekie&a/c doctor

Piston will only come out through the top,so it will be cylinder head off .Not an economic repair on a car this age.Plenty of good astras out there for less than £1k
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Mon 12 Jun 2017 14:50
Vauxhall Astra 1.8 petrol - Piston replacement - hardway

And you'll probably need a hundred pounds of tools that your never going to use again.

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Mon 12 Jun 2017 19:16
Vauxhall Astra 1.8 petrol - Piston replacement - skidpan

Can anyone tell me if the sump is easily removable to allow big end cap to be taken off so I can draw the piston out,

Even if you took the sump off in situ and removed a big end cap there would still be a large component in the way preventing you from removing the pison/rod. Its called the crank. To remove the crank requires a major engine strip and its not an in car job.

Give up now unless you have a suitably equipped worshop.

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Mon 12 Jun 2017 23:41
Vauxhall Astra 1.8 petrol - Piston replacement - focussed

A bit of lateral thinking here.

Buy/borrow/hire a borescope - Lidl were doing a brilliant model recently for about 50 quid, I've got one that I bought a couple of years ago, the camera head is only 8 mm diameter so will easily go down a plughole then you can have a look around inside the cylinder without taking the head off.

I had a plug break up a long time ago on a tuned MGB engine - the side electrode came off a Champion N9Y. I took the head off - no sign of it or any damage, it must have got spat out via the exhaust valve.

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Mon 12 Jun 2017 23:34
Vauxhall Astra 1.8 petrol - Piston replacement - Big John

· Hmm - there is a reasonably high chance that the bore will be damaged anyway - game over

· Even if you are lucky(itsh!) it's not a trivial job. Sump and head off job both difficult jobs with engine in situ.

· Then even if bore OK if you just replace the piston and rings (you'd need to check if engine has been a re-con in the past and is fitted with oversize pistons) you'll potentially need stepper rings (er if available these days) so that the top ring isn't damaged by the step in the bore. You also need to check every ring in the bore before fitting to the piston to check gapping. You also have to be very careful not to allow any dirt into the oily bits (hard in situ). I've done this sort of thing with old engines in the past and it wasn't always successful (eg oil burning afterwards or cam failure due to dirt).

· I soon learnt a proper rebore/regrind/rebuild in clean conditions was the answer (and actually quite satisfying/enjoyable)

· Basically for a 53 model it's probably not feasible

Edited by Big John on 12/06/2017 at 23:36

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