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Hey everyone, I recently noticed my gtr would blow a heap of white smoke just after I've warmed it up, so I figured I'd check the coolant and oil. The oil was about half and the coolant was pretty much gunk from the missing oil. So I did a few searches and it turns out that there is a few possible causes, 1. Blown head gasket, 2. Stock oil cooler has failed and either a cracked block or head. Just wondering if anyone who be able to help me out by leading me in the right direction.

The motor is only freshly built with forgies, acl bearings, n1 pumps and a cometic mls head gasket sprayed with some head gasket spray( I forget the name of it but my mate who's a diesel mech said it would be a good idea to be safe). It wasn't smoking until about 3 days ago and oil pres looks fine on a auto meter gauge and I haven't over heated the motor at all, it's always been at half way on the gauge. Although I have upped the boost to 14psi on the od occasion. So I'm kinda stump to what it it could be.

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Did you use arp head studs on your new motor?

It's a must with big power 26's. Especially if you didn't face the head or block.

I'd say head gasket failure. Do compression test and go from there. Good luck

Seeing as you recon blowing white smoke.

pull spark plugs you could find the problem.

you may find crap in a cylinder, sure sign head gasket.

but a blown head gasket doesn't always leak into cylinders.

oil in water is oil gallery to water path, proberly head gasket.

as for the special sealant guess that's not working hay.

why was a sealant recommended for head gasket, what was it supposed to do / help / fix ?.

My monies on cracked block if its got ARP head stud kit, or porrus holes in bores. Have a look at the block on the exhaust side were the oil feed banjo bolt goes into block... look for coolant stains (white-ish green) As someone else also suggested remove ALL spark plugs and if have access to bore scope is best to look inside, if not look for odd coloring on plugs. make sure you keep plugs matched to cylinders so you know were to look once you strip down engine. Hate to bearer of bad news bad you will be at best taking the head off. Ive never seen an OEM heat exchanger leak,crack,fail in 15 years of doing GTRs...

The motor is about 1500km old, I had the block resurfaced but not the head, I just used the stock head studs and yeah it was the hylomar stuff we used just incase the head was warped.

Like Dan said, they say on the install instructions not to use hylomar or similar as there is already a coating on the gasket. Also the finish on the deck should be ok but if the head wasn't skimmed it might not be a fine enough finish for the use of a MLS gasket? (cometic recommend a 50ra finish, but I have no idea how to measure that). And if the head might have been warped (in which case i wouldn't think standard head bolts and a metal HG are going to be the best option..) then the best way to ensure it isn't is to measure it and get a truing cut if you need so you don't have to pull it apart to do it again, which is what you're going to need to do unfortunately

Edited by doo doo

And if the head might have been warped (in which case i wouldn't think standard head bolts and a metal HG are going to be the best option..) then the best way to ensure it isn't is to measure it and get a truing cut if you need so you don't have to pull it apart to do it again, which is what you're going to need to do unfortunately

Is the old skool straight edge + feeler gauges check worthwhile doing first, rather than going straight to getting it skimmed?

Is the old skool straight edge + feeler gauges check worthwhile doing first, rather than going straight to getting it skimmed?

Yeah, that's what I meant by getting it measured, no need to skim if in spec. But would still be looking at the surface finish when using a metal HG too, maybe stock finish is ok.

The motor is about 1500km old, I had the block resurfaced but not the head, I just used the stock head studs and yeah it was the hylomar stuff we used just incase the head was warped.

Were the head bolts you used new, were they tensioned up to the right torque in the right order according to the workshop manual?

It would have been a good idea to skim the head warped or not, for $80-100 it's worth knowing your head is flat and has a good surface finish for sealing.

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