[samboy1123]

Hey Everyone,

This is my first post so be nice lol. Ok so heres the story, I just purchased a 1995 Zook all stock 160000kms, everything seemed fine when i got it now about 5000kms later it has an annoying ticking noise and theres blue smoke coming out the rear end. Not sure if these two things are connected, the ticking noise started about a month before the blue smoke, sounds top end, I've checked the clearances they're all spot on. Thought it may have been the fuel pump so replaced that but no change. The ticking noise is loudest under acceleration but constant throughout rev range and ideas on what this could be would be muchly appreciated. As for the blue smoke I know this means its burning oil but I can't figure out how its getting into the compression chamber, have pulled plugs only number 3 was oily, done a compression test all cylinders sitting at 175. There is no noticeable smoke coming out the oil filler when its taken off however there is a small amount of oil in the air filter housing. So at the moment Im thinking its valve stem seals or piston rings am I heading in the right direction?

Cheers.

[samboy1123]

Oh and I forgot to mention its a sierra with the standard engine.

[zooky08]

Most likely valve stem seals.

[samboy1123]

Thanks mate,
I had a thought today that it might be the pcv valve, only because I read that the when the valve stem seals are shot it smokes alot on startup which mine isnt doing. So then i took the hose off the pcv and realised that it was full of oil could this be the culprit?

[mrgtt34]

with 160k on it its due for a build

[FullyZooked]

When does it smoke? Under acceleration,backing off engine braking or on initial startup?

Valve stem seals will rear their ugly head under hi vacuum conditions such as changing gears or deccelerating. They can also weep when the car is left stationary and you get a good puff of smoke on startup. When the car is up to temp the smoke should reduce to next to none.

Rings on the other hand will produce smoke almost always. More pronounce under acceleration. Plugs will foul and oil consumption is increased. This is unlikely given your Comp readings are good and you only have one juicy plug.

Before you go hacking into it an easy check to determine the cause is a leak down test.

[samboy1123]

Thanks for your help mate,
Only smokes under acceleration, some puffs appear to be random but no smoke upon startup. Did notice today that there was a fair amount of blow-by but Im not sure what the normal amount is. My pcv valve was also blocked but Ive unblocked that now, which made the car idle faster. Don't know a whole lot about pcv valves but Im pretty sure they shouldnt suck at high rpm although mine is so I will replace it shortly. thanks for the help.