Blown Head Gasket?

[MattiasJacobs]

Alright, I've been dealing with a lot of cooling related BS since I've had my car. All of them being visual leaks on Heater Hoses, Rad Hoses, etc. After fixing a recent broken heater hose I notice some corrosion in the water lines. I decided to take it in to have a good coolant flush done. Everything checked out fine at the shop with the road test blah blah blah. When I picked it up I took it for a drive nothing unordinary was happening. Mind you the coolant has been bubbling sometimes boiling once the engine is shut off but hasn't had any irregular water temps while running. After I parked it in my garage for an hour I noticed it dripping coolant again. I figured It was the old heater hose that leaks only when I have the Godspeed 1.1bar Cap on (I run an OEM 0.9 cap on a Godspeed rad since I noticed it was over pressurized). Well seems coolant is dripping off the front of my block and has no visual leaks above the head... Comp test done earlier this spring 160's. No coolant in oil/ No oil in coolant. No smoking since I switched my oil soaked OEM turbo's. Any Idea's on this topic? If my HG is gone I have no problem forgetting about this car until a full rebuild can be done. On the other hand if I'm missing something stupid help would be appreciated. Pictures can't be added till I fix my broken car jack.

[bobbo]

I'm going to guess from what you say that it's the "tell tale" in the water pump. Water pumps have a hole in the bottom of them that is designed to leak when the pump seals start to go.
If I'm correct go get yourself a new timing belt, tensioner, and a new water pump.

[MattiasJacobs]

Timing belt was done at 94xxx, 140xxx on motor now. No idea about the water pump. The block is soaked on the turbo side. Thing is I'm looking for a rebuild excuse anyways and I think my HG is on its way out. Plus itd be nice to get the full potential out of my new 2860-7's.
Clarification with anyone else on water pump?

[MarusGTR]

The waterpump's "drain" is a square hole on the bottom of the block to pump flange, left front side of the block (intake plenum side). The "Nissan Skyline RB26 Service Kit" is produced by nissan for maintenance at over 100000kms and includes oil pump, belts, timing pulleys and timing belt.

I'm loosing coolant too and I don't know where from since the exhaust fumes are clear and I dont make puddles when running or not. I'll be doing the maintenance kit anyway since I have 130000kms.

Also, you're due soon for a timing belt, they're rated for 64000kms.

[MattiasJacobs]

Good to know. That sounds like a headache though. Frankly I'm getting sick of problem after problem with this engine. Its getting old and I think I'm just gonna park it for a couple years, man up and get a rebuild done.

[markc32]

coolant drain plug is on turbo side of block.....core plugs are there tooo

put ur car on hoist n let it idle and look for external leaks.....

it aitn hard to find that leak....

[Skym]

Never run a higher pressure radiator cap on stock cooling system, stock radiator. Need to upgrade to metal headgasket, higher pressure brass welsh plugs (common upgrade on Group-A RB26 engines), radiator (thicker) before fitting a higher pressure radiator cap. From what I understand, higher pressure radiator cap compensates for a larger radiator that could drop pressure in cooling system or is used when using a air separation tank.

About the part when engine is turned off, RB26 is known to suffer from airlock, where bubbles form in coolant and cause overheating problems. RB20, RB25 not so much, as high point is on intake plenum, so above radiator, top of engine, but they can benefit from a air separation tank. An air separation tank (creates a new high point) removes these bubbles, but requires a higher pressure radiator cap, so should be done when headgasket, welsh plugs, etc are replaced. Just lucky it didn't pop the welsh plugs on front, rear of head or create a leak at waterpump, which are common area's to fail on RB26.

Not the engines fault, just you didn't know that fitting those mods does that sort of damage.

[markc32]

yup higher pressure cap on a stock set up = coolant leaks normally hoses bursts ie ur heatercore hoses first then some serious stuff...

[MarusGTR]

Never run a higher pressure radiator cap on stock cooling system, stock radiator. Need to upgrade to metal headgasket, higher pressure brass welsh plugs (common upgrade on Group-A RB26 engines), radiator (thicker) before fitting a higher pressure radiator cap. From what I understand, higher pressure radiator cap compensates for a larger radiator that could drop pressure in cooling system or is used when using a air separation tank.

About the part when engine is turned off, RB26 is known to suffer from airlock, where bubbles form in coolant and cause overheating problems. RB20, RB25 not so much, as high point is on intake plenum, so above radiator, top of engine, but they can benefit from a air separation tank. An air separation tank (creates a new high point) removes these bubbles, but requires a higher pressure radiator cap, so should be done when headgasket, welsh plugs, etc are replaced. Just lucky it didn't pop the welsh plugs on front, rear of head or create a leak at waterpump, which are common area's to fail on RB26.

Not the engines fault, just you didn't know that fitting those mods does that sort of damage.

Interesting facts, thanks man. For my case, I'm pretty sure I'm (was - now stored) running bubbles in the system because I was always running a little higher than 100C. Thing is I thought the coolant high point was the air bleeder plug near the intake manifold. I put some more coolant (like i said my fluid is leaking or evaporating somewhere) while idling the engine and then shut it off to take the off the air plug. Thought it would of done the trick but it didn't.

[MattiasJacobs]

Never run a higher pressure radiator cap on stock cooling system, stock radiator. Need to upgrade to metal headgasket, higher pressure brass welsh plugs (common upgrade on Group-A RB26 engines), radiator (thicker) before fitting a higher pressure radiator cap. From what I understand, higher pressure radiator cap compensates for a larger radiator that could drop pressure in cooling system or is used when using a air separation tank.

About the part when engine is turned off, RB26 is known to suffer from airlock, where bubbles form in coolant and cause overheating problems. RB20, RB25 not so much, as high point is on intake plenum, so above radiator, top of engine, but they can benefit from a air separation tank. An air separation tank (creates a new high point) removes these bubbles, but requires a higher pressure radiator cap, so should be done when headgasket, welsh plugs, etc are replaced. Just lucky it didn't pop the welsh plugs on front, rear of head or create a leak at waterpump, which are common area's to fail on RB26.

Not the engines fault, just you didn't know that fitting those mods does that sort of damage.

The 1.1 cap I ran with maybe 3 times came with the Godspeed rad. I was always skeptical about it. I find it stays pressurized way too long after shut off. But the rad makes an erie noise when the 0.9 cap lets pressure off...

[MarusGTR]

The 1.1 cap I ran with maybe 3 times came with the Godspeed rad. I was always skeptical about it. I find it stays pressurized way too long after shut off. But the rad makes an erie noise when the 0.9 cap lets pressure off...

lol erie sound, sorry that made me think of when you'd shut off the engine you'd be hearing the friday the 13th's *tsh-tsh-tsh-hah-hah-hah* *looks over shoulders*

[nbskyline]

hate to say it but my coolant did the bubbling/boiling thing for 3 months before my headgasket went.....temps were fine, ran fine, then blah, coolant leaking out of my cat and downpipe. Try a compression test now. When i removed my 5th cylinder spark plug, it was full of coolant. Hope it is just the water pump, easy fix. Keep us updated.

[MattiasJacobs]

I'll probably double check on a compression test soon. I think my safest bet right now is to work on a rebuild fund. It's the only thing that will satisfy me...

[bellis_GTR]

Sorry to OT but I thought Id post here instead of making a new thread.

Im scared my head is cracked! I have oil mixing with water but very light oil. I had heater hose leaks and turbo line leaks, fixed them. Had thermostat housing gasket leak, fixed that checked thermostat and it opens. I just got a new oem rad with upper and lower rad hoses. New water pump about 2000-2500km.

The car drives fine until oil temps get up to 80 degrees in the first 10 mins of driving. Coolant temp is still under the cold line and their are no leaks?

Could this be the same issue? anyone have the same symptoms?

[bellis_GTR]

hate to say it but my coolant did the bubbling/boiling thing for 3 months before my headgasket went.....temps were fine, ran fine, then blah, coolant leaking out of my cat and downpipe. Try a compression test now. When i removed my 5th cylinder spark plug, it was full of coolant. Hope it is just the water pump, easy fix. Keep us updated.

The same thing happens with mine. Water is running down the down pipes. What could that mean? I changed the heater hoses and got new clamps for them.