Jump to content
SAU Community

Rb20/det Head-gasket: Queries + Opinions Help


Recommended Posts

Hey all,

Currently doing many a upgrade to my R32 RB25DE+T..

Please take the time to read, all help extremely appreciated + theres some cool trick info some of you may not know..

CAR runs all sensible mods, factory boost, premium fuel + fluids and is treated with the up-most respect, engine was in good cond. so I thought..

Currently in the stages of upgrading my Head-gasket to an RB26 Item, along with new, genuine C/belt kit, genuine N1 6F Water Pump Etc.. Before the real fun begins :)

Ill cut a long story short, I got this thing running properly a few weeks back and it was great fun, however I ended up plumbing both breathers right up before going on a drive one day, returned home, popped bonnet like usual.. and found my dipstick pushed slightly out of its tube (blow by), oil on the strut tower etc + a little oil in my coolant and vice versa.. NOTE: CAR NEVER GOT HOT, CAR NEVER BLEW SMOKE..

NOTE: Oil return from factory turbo was aftermarket, did not drain properly, caused oil back pressure in turbo core/seals.. Would this cause major damage?

I opened up both breathers on the valve cover and went for another drive.. NO blow by at all BUT there was definitely more oil in my coolant and vice versa, car was NOT blowing any smoke at all.. I also noticed a small (very small) amount of oil by one of the M6 bolts on the back of the head..

So I at this stage thought the Head-gasket was gone and began going too work.. (With the motivation of a set of GTR 440's a Z32 AFM, oh and new compressor ;)

I got down to the Head-gasket expecting to see some damage but there visually isnt too much at all? Which I know doesent necessarily indicate that there is no damage, was just surprised..

BUT I did notice one of Head Bolts (Further-est rear, #14..) was a little tighter to remove and had some very light dry cooling system rust on it, rather than nothing but oil like usual.. The gasket was also slightly different in the area where the 14th Head Bolt sits.. slightly different in colour and feel. slightly.

My question(s) is this:

*Would/Could having both breathers plumbed right up + having a very poor oil drain from the turbo.. Possibly damage the seals in the core enough so coolant/oil could mix?

*Is there any other way oil and coolant would have mixed due to the blow by in my crankcase etc?

*Im 99% the Head-gasket is gone (I was so sure I didnt even PK test it).. but I was surprised to see the Head-gasket wasent visually damaged, is this usually the case or?..

*Finally, Its sweet to rotate the engine and check the bores, right? As long as I line it back up in the EXACT same position, this should be fine right? haha

Cheers guys! :)

Link to comment
Share on other sites

1:no

2:heat exchanger/factory oil cooler

3:deoends how good your eyes are

4:yes.

Is it tuned? I suspect that is your problem.

Ugh, Im not gonna lie, it had a tuned EPROM in it for an R32 with the mods I had, absolute shit tune, I retarded timing and raised fuel pressure to 3.75 and then 4.00 kg/cm2, there was no knock to the ear, Im pretty sure a knock sensor would have picked something up on a dyno..

Intake, 2.75" Piping with GT-R sized I.C core, RB20DET A.F.M, RB20DET INJ, ADJ F.P.R, Walbro 255LPH F.P, Factory manifold w/ R34/VQ30DET N1 GT28/30 at 9 P.S.I.. Chipped Eprom (I always wanted to upgrade the Injectors, turbo, afm and supporting parts and was planning on getting NISTUNE Board Imported when I did, I have a mate up the road here in NZ with lisence etc..

Which is happening as we speak.. Ahh Heat exchanger.. Is that located inside/next to the heater core? And its Factory Manual so no Trans oil cooler in radiator if thats what you were meaning? Im unaware af a factory oil cooler on R32 GTS25 Type M's ;) haha

Edited by Paulusc44
Link to comment
Share on other sites

Question..

Can I delete/re-route/loop my heater hoses? Ill simply run my turbo feed line for my turbo from somewhere else with suitable pressure (Theres a hundred places I could think of) I see no need for the hoses if Im going to remove the heater core + exchanger? Just extra piping for it too work its way through. surely I could Loop the feed straight to the return (on the block)?

Link to comment
Share on other sites

Heat exchanger sits under the oil filter. Oil-water HX for faster start up warm up and some oil cooling once hot. Susceptible to corrosion death in engines with poor coolant change history.

Don't f**k with coolant lines if you absolutely don't have to.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share



×
×
  • Create New...