Seven Months after I rebuilt this Engine and i get a Miss on number 5 and low compression reading of (Zero) :cry: and number 3 cylinder reads 115psi due to strangely a head bolt between 3 and 5 cylinder working loose?

So whats wrong with this picture?? I don't think its PTU or Coilpack related :D

The last picture is an example of how much room there is when you remove the passenger side head while in situ! Great i can easily get to those gearbox bolts now! :rofl:

I started stripping down at 9:30am and was finished by 5pm ready to have my tea Lol!

Everything that was removed would have had to have been removed regardless of whether the Engine was removed or not!

I was iffing an buting about doing it in situ but i found it quite easy for my first time of doing it in Situ!

Piece of advice! if ever you are going to remove the head on the passenger side! Leave the exhaust manifold and turbo bolted to the head and manuvere it round the stearing column and it will lift straight out!

Hmmm, that's proper broke. And a nice collection of dead leaves too ! :D

Hmmm, that's proper broke. And a nice collection of dead leaves too ! :D

Its amazing what can build up on the Engine since November?? Lol

Do you want to buy some Andy?? :D

Hmmm, that's proper broke. And a nice collection of dead leaves too ! :D

I am still not 100% sure what caused the Valve to break? and the Turbo was amazingly unharmed!

I am puzzeled by the Clean marks on all the pistons although that could be from the Injectors or Pre-Ignition or Running too lean?? :confused:

I have not cleaned the Pistons thats how they looked when i removed the head. They have just had a gentle wipe over!

did you have it skimmed?? if so has it been skimmed before?? if so then that could cause the damage, pistons look in pretty good nick, nothing would suggest must detting ontop of them.

did you have it skimmed?? if so has it been skimmed before?? if so then that could cause the damage, pistons look in pretty good nick, nothing would suggest must detting ontop of them.

Skimmed once last year! This is the good head Lol! The other heads the Very low head and i am very surprised as thats ones ok? with reasonable Compression.

were your plugs ok or where they damaged??

were your plugs ok or where they damaged??

Plug's were Fine Mate.. ;)

proberbly just a weak valve could of had a hair line crack in it and if the engine has been detting it has caused the crack to break off. All i can think of, but where has the broken bit gone if there is no damage to piston and turbo?

At least the little piece didn't go into the motor. I guess the turbo must have been at a very slow speed as the piece passed through or there would have been more damage (just guessing) which would suggest it happened on startup. LUCKY

proberbly just a weak valve could of had a hair line crack in it and if the engine has been detting it has caused the crack to break off. All i can think of, but where has the broken bit gone if there is no damage to piston and turbo?

I was on the M27 the time it went Lol did not know anything about it untill i came off at junction 3 and stopped at the lights. Piece could have exited through the Waste gate if it was open?

Still can't work out why one of the Head bolts worked loose (Hand tight) as they were all torqued down in sequence and had a final 90* turn?

Close-up of valve

Close-up of valve

 

its an excuse to go bigger valves :p

its an excuse to go bigger valves :p

looking at pics mr nissan dont seem to have given us much room for bigger valves that would make a vast improvment

Doesn't look like there's a mark on the piston, the bit must have blown straight upwards (See below for what a broken valve does to a piston).

 

 

Are you sure the part isn't stuck somewhere ?

looking at pics mr nissan dont seem to have given us much room for bigger valves that would make a vast improvment

 

you can go 1mm over sized which will be an improvement but tbh only if you are chasing big power ;)

Doesn't look like there's a mark on the piston, the bit must have blown straight upwards (See below for what a broken valve does to a piston).

 

 

Are you sure the part isn't stuck somewhere ?

I have looked in the exhaust manifold and in the turbo and nothing :confused: Maybe the valve fairy's stole it :rofl:

I have looked in the exhaust manifold and in the turbo and nothing :confused: Maybe the valve fairy's stole it :rofl:

it might of been eroded in a flash as opposed to snapping,have you checked in the ashtray or under the spare wheel :D

More update's :D

Valve Guide is slightly damaged and valve seat....

could be whatever's been nesting in the engine bay has sneaked in and nibbled a bit off the valve....

youve been very lucky that the missing bits not done a lot of damage, that could seriously have fooked the engine

 

some one above is looking down on you !

Dunno what year yer Z is bud, but i remembered some info on TT.net about this kinda thing, read the link http://www.twinturbo.net/net/viewmsg.aspx?forum=technical&msg_id=916703

smithy

Dunno what year yer Z is bud, but i remembered some info on TT.net about this kinda thing, read the link http://www.twinturbo.net/net/viewmsg.aspx?forum=technical&msg_id=916703

smithy

On the Registration document as year of Manufacture 1989!

So a Very early one ;) One of the ones that were suppossed to have Engine trouble :confused: