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veeone
14-06-2012, 03:07 PM
Anyone know what the compression pressure is on the 4G54 cylinders from new as want to compare what i got on a recent compression test (180psi on 3 cyls and 160 on 1). Cheers Vee

magnaman89
14-06-2012, 04:17 PM
1250 t0 1300 kpa that's about 180psi

MadMax
14-06-2012, 07:47 PM
10% variation is acceptable if I remember correctly. Might want to try it again down the track though, to see if the variation is getting worse. Could be a valve - usually exhaust - not sealing due to carbon buildup or hot gas erosion, less likely to be rings.

Old school stuff, that is, working out the condition of an engine from testing the compression and looking at spark plugs!

veeone
17-06-2012, 03:32 PM
Thanks for that info all!!
Yeah no 2 cylinder has been like that for about 5 years. When i got the car it was a carby and the charcoal cannister had failed and the carby sucked in a huge amount of charcoal and one of the vavles on that cylinder was stuck open a little and the previous owner drove it on 3 1/2 cylinders for a bit so i think there is a little erosion on a valve but has not got worse so must be quite small as would have burnt by now. Converted it to EFI when i got it and put the carby on another car i had after i cleaned it. I need new valve stem seals which i will do next month but as my workshop manual is not with me at the moment i needed to get some stats for compression check. Cheers