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Just done a compression test.......

 

On taking the plug out of the middle right cylinder alarm bells started ringing, oil all over it.

 

results are

 

145 V 80

140 V 30

140 V 135

 

So thats it then, now I have a desision to make, break it or fix it

 

Im totally 50/50 at the moment

 

I really want to get shot of it and get something simple that I will actually get some enjoyment out of, caterham perhaps. I dont see the point of having a big GT car just for the weekends when i might as well just get a proper track car. But then again I have spent so many hours on it getting it just right and it was almost there, I do enjoy shows and meets as well. :mad:

 

what can i say - gutted, but strangely relieved :wack:

Featured Replies

oh dear, more & more people are breaking there zeds :o

 

but its understandable with the expense of stripping the engine out & rebore,

 

well its decision time, while the engine is out forged internals & bigger tubs, now is the time if you wanted to go that way,

 

some very helpfull zed mechanics here why not ask them for a quote then you can decide which way you want to go :tongue:

 

i have a spare tt engine that i have stripped down to do a full rebuild but i dont have the time to carry on with it, comes with new piston rings & valve stem oil seals if your stuck.

 

good luck matey :)

i feel for ya bud, iv been in and out of this feeling many times... so far iv just battle through. i really enjoy zedding and i dont think il get the same enjoyment from any other car, let alone a similar community. Give paul@swz a call and go through some options with him and see what ur looking at price wise, then take it from there :)

 

otherwise, if you do decide to break... dibs on your hardpipe kit with bovs ;)

 

Joel

sorry to be a newbie but what does the figures mean? i know nothing about compresion testing or even compresion :)

 

145 V 80

140 V 30

140 V 135

 

what should the figures be ?

and would you definatly know if your engine had a compresion problem, or a problem atleast, without gettin it checked ?

Compression testing shows the condition of the pistons/bores/valves/head gasket... Those figures show some pretty serious piston damage on the lower values, either cracked ring lands or holed pistons....

surely thats a headgasket prob rather then a fooked cylinder. seems like the two are leaking into each other.

 

HG would very doubtfully cause figures as low as that. I presume the lower figures were on the passenger side bank? Thats the most common side to go and quite normal to drop the rear two....

I get paranoid really easily and i see somthing bad then i think "damn hope i dont have that"

hypercondriac of the car world

  • Author

Right i will price up repairing and what I could get if I break it and get back to you all!

  • Author

Not sure what is happening to the passenger side back cylinder as only getting 80psi but the spark plug looks fine. The passenger middle one is soaked in oil but there is no oil in the coolant etc, so headgasket should be ok. I dont understand why I am not getting huge clouds of smoke out the passenger side zorst tho as I should be imo. I double checked all the passenger side to make sure wasnt the tester playing up but got the same values again the second time.

 

Now I know why its lumpy at idle! its on 5 and a half!

Not sure what is happening to the passenger side back cylinder as only getting 80psi but the spark plug looks fine. The passenger middle one is soaked in oil but there is no oil in the coolant etc, so headgasket should be ok. I dont understand why I am not getting huge clouds of smoke out the passenger side zorst tho as I should be imo. I double checked all the passenger side to make sure wasnt the tester playing up but got the same values again the second time.

 

Now I know why its lumpy at idle! its on 5 and a half!

Could be rocker cover gasket. Mine is doing the same. Shit myself when i pulled the plug out and it had oil on it. Then had a look down the hole with a touch and saw a puddle before the plug's lip :smash: The car isnt using any oil so i guess its just weaping a little. Will sort it when i do the plenum swap. :dance:

It depends which ring lands have cracked - if it's between the compression rings and not on the oil control ring then oil will not get to the plug but you will still lose compression and blow the dipstick into the bonnet lol.... Trust me, I've been there ;)

  • Author

So how much we talking andy?

 

To pull the engine, get my turbos recon'd, new down pipes, decats, pistons, gasket set, fluids etc and labour. Maybe another set of plugs as well.

 

pm me or give me a ring

Will give you a bell tomorrow bud :)

 

Cheers,

 

Andy

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