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after rebuilding and replacing the turbo a valve has let go on the 'test run'

this was only at 10psi and under 5500rpm so not heavy conditions. at first it was a misfire so i changed coil packs, spark plugs and ignitor amps. nothing. ran a compression test, and it came up with 0 compression in cylinder 4. so it something to do with the valves

i pulled the rocker covers off and rotated the cams and all 4 lifters work fine so its not the valve springs. all looks fine from the top of the engine. so it must be a bent valve or something from the bottom... but does anyone else have any ideas? is there something ive missed in the diagnostic?

can anyone give me any advice with regard to pulling the head off to check from the bottom if a valve is stuffed. how much for a workshop to do this kind of job or any help is greatly appreciated. my budget is already stretched from the turbo job so i have little cash to play with

thanks in advance for any help, it is much appreciated

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Originally posted by adam 32

thanks, i will definately need valves, hopefully not pistons - how much you want per valve?

how could the 2 have been related? im writing it down as bad luck as i was only running the new turbo at 10psi... any thoughts, ideas?

maybe a bolt or sumthing hard acidently fell into inlet side and bent valves

let us now what actually happened ie bent or burnt valves or holes in slugs

never seen a rb20 burn a valve yet

vavles...... $10 ea

Removing the head, dont use alcohol.

Big job, if you choose to accept it yourself

elaboration, ever notice how on a rb twin cam how something could fall into teh exhaust manifold and land right on number 4, its teh most direct route..

A mate once found a micromachine in teh sump of a 253, might find that lock nut after all

yep several times

I dont know how fast you work but put a weekend aside

veale should be able to get your head gasket over.

if you do it yourself theres two 10mm headed bolts holding head to block on the rear two corners on the outside of the head.... dont forget em dont screw up for timing belt settup......

workshops ...... contraversial and political

theres two in bentley area id trust

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