A couple weeks ago went to Jeffs,not for any work,just while there did Conzult,no probs except lazy O2 sensor,anyway,to me it sounded a tad noisy,had a small hollow knock ,but then alot of zeds do,but to me it sounded higher and in genral not that smooth,anyway couple days later started car,went for run and at low speed it was uneven,choppy,you could just feel it coming through the whole car,but at over 2000rpm all ok and still performs realy well,but,in the back of me mind i knew it was not all well,so today shot up to Jeffs,conzult,turns out that No6 piston low compression,80psi dry test+100psi wet,all other pistons reading around 145psi,the Conzult when doing the individual piston switching on/off showed up red on No6,so all plugs out they all ok,swapped No6 piston plug with another and put all back,Conzult showed all to be ok(not red on N06)but of course the compression has given it away as to the problem,so the diagnosis/conclusion is a fooked/chipped valve,or fooked piston/chipped/com rings?,so what to do,engine re-build,or just the head(if its valves,)or replace with yet another engine(the third!)or seeing as if i get a second hand engine will i end up in the same position!I am not to gutted to be honest ,as i half expected something like this sooner or later,i knew the history of car verywell before i got it,plenty of drag strip runs,Rockingham speedway and more,but when you look at whats been done to this Zed since it was imported 3 years ago and the amount of serious money spent it was and still is worth everypenny i paid for it,so,what to do,bear in mind i aint loaded at the mo unless i win the lottery,but i aint not gonna fix it!Any suggestions/advice/help/sympathy wellcome:D

I have no advice but you have my sympathy.

 

Stuart

Commiserations Mate

 

My only advice is on the rebuild remove the freeze plugs on the block and remove the old casting flashing which hinders coolant flow to cylinders 5 and 6!

 

Mark

So, just to be clear, you said :-

 

"No6 piston low compression,80psi dry test+100psi wet,all other pistons reading around 145psi"

 

Does that mean No6 tested 80psi dry and over 100psi wet, or 180psi wet ?

 

If it's only a little over 100 then the problem is likely to be topend rather than piston seals. So a rebulid of one head, or even just a head gasket replacement may be all you need.

Andy, No6 tested 80psi dry and over 100psi wet other 5 pistons tested around 145 dry,;) Anyone an idea as to what this may cost depending on what option i go with,not to sure at the moment,and any idea who best to do it,bearing in mind i dont realy want to be without Z for weeks and weeks on end:D

Impossible to guess what it might cost. You need to get that head off in order to assess the damage. Good luck, you may need it.

Yep could do with some luck,but at the end of the day it can be sorted and there are worse off than me latley,especially those fighting abroad,and a mates 29yr wife has had a heart attack couple weeks back,puts things into perspective to say the least,so i am quite chilled out over it really:cool:

Well said.

Hi Tony,

 

Feel for you mate. I have had nothing but a bad run of luck with my car, one job after another non-stop, so I know what its like to be in the doghouse with these cars, although, theres ALWAYS someone worse off, no matter how bad things seem.

 

But like you say, chin up as new turbos will be fitted soon and hopefully I will have at least 3 months of trouble free driving....

 

not counting my chickens though......

 

best of luck mate.....;)

Tony - find a garage with a Cylinder Leakage Tester. you can accuratly diagnose the problem then.

 

as Andy suggests - it does sound top end if it only rises by 20 psi with oil in the bores

Thanks lads,Paul i agree may just be top end,but to be honest i think if i just get that done sooner rather than later bottom end will not last to long,the engine sounds too loose and in genral ratley/noisy when ticking over prior to this happening,there is allso a salvage breakers near me with 6 engines on the shelf,will ring em just to see what they want for a low miler one:eek:

I appreciate it's a very different car, but on my S13, three cylinders were 160 psi and the fourth 110psi. Symptoms were lumpy idle and high CO2 readings but absolutely normal running at higher revs. Turned out to be a burnt out exhaust valve.

 

Is your car smoking?

Yes JonJon it is a little smokey on the same side outa zorst as the piston/valve with the trouble,but clears when not on tickover,allso when bonnet up you can if you blip accelerator hear a slight clicky metalic sound above the poorly side of engine,must be a valve?then as revs come up it goes away, dissapears completely,and i have no discernable loss in power when normal driving!;)

i havnt got any advice Tony but i hope all turns out for the better for you :)