Outer Limits 4x4 Board

hey guys have a 6.2 chev diesel in a gq have had for 40thousand klms now and its had a pretty good floggin. as of today its blowing excessive oil out the dipstick and its quite smokey. when i say excessive oil im talking about a ltr of oil just giving it abit of a thrash around the block. 3klms max...
im assuming sumthing is wrong as its not done it before?
my guess is crackd rings? causing the sump to pressurise. maybe a valve? but i dont see how that could blow the dipstick out or a hole in the piston? i know for that much oil it couldnt be somthing as simple as a dodgy sealing dipstick surely? however the dipstick is quite a loose fit . if anyone can share there wisdom on what may be at fault its greatly apreciated. either way its guna be rebuilt but would just like to have a good idea of the cause so i know what to curse about..

sounds like a buggered ring, cracked pistion yes. Like you said a rooted valve wont pressurise sump. Just squash the top of dip stick tube so it stays in!

i had a mate i went to tafe with he had similar fault cable tied dipstick in

burleygu wrote:hey guys have a 6.2 chev diesel in a gq have had for 40thousand klms now and its had a pretty good floggin. as of today its blowing excessive oil out the dipstick and its quite smokey. when i say excessive oil im talking about a ltr of oil just giving it abit of a thrash around the block. 3klms max...
im assuming sumthing is wrong as its not done it before?
my guess is crackd rings? causing the sump to pressurise. maybe a valve? but i dont see how that could blow the dipstick out or a hole in the piston? i know for that much oil it couldnt be somthing as simple as a dodgy sealing dipstick surely? however the dipstick is quite a loose fit . if anyone can share there wisdom on what may be at fault its greatly apreciated. either way its guna be rebuilt but would just like to have a good idea of the cause so i know what to curse about..

I had the same problem on my 355 stroker...turned out to be the head gasket blown out into the valley on number 3 cylinder...mine started to get smokey above 2000 rpm...also coulnt stop the bastard leaking..do a compression test as a start..good luck

Doesnt sound good but i would check and make sure your pcv or breather is operating correctly or there is no blockages.

Srooted, comp test it

6.2's and 6.5's are HEAVY breathing hunks of junk, but spitting a litre of oil on a hot lap aorund the block, means you got some serious blowby

ok guys motor is completely stripd and the final result is the rear drivers side piston has cracked. and 1 ring was broken. we suspect it all happend when i was towing my boat home. how the piston broke to me ' no profesional ' but looks like a bad cast. along with stripping it down found the bearings are badly worn and the timing chain is loose. am lucky that only 1 of the rings broke and the oil ring and the top ring held the broken peice of piston in place. am very furtunate it didnt ruin my bore of block for that matter

So have you checked the main bearing webs for hairline cracks??

These 6.2's are renowned for cracking the main bearing webbing. I got a 6.5 turbo in from the US for a good price, the turbo looks in immpecable condition with everything there to bolt straight up, BUT this is something that's worring me and stopping me from bolting going ahead with it all. Ohh, by the way, I'm running 6.5 heads on my 6.2 engine too!!

Where are you sourcing all your parts from??

hey brighty im getting all my parts from lynquip in gympie qld lyndsay is a great help. and his prices are very reasonable for a replacement piston and rings big end bearings and gasket kit costing me 370 bucks and its all in the post already. am unsure weather or not im guna check the main bearings and yes i know i should but to do that i have to drop the crank and i may aswell remove the engine if so and i dont really wish to do so....

It makes more sense to check and do it now just in case there is a problem rather than having to do it at a later date.

If that means pulling the motor then so be it.