Jump to content
SAU Community

Recommended Posts

Mafia,

Did you do a compression test when it was cold and also after when it's warmed up?

Possibility the head isn't torqued properly as well, hard to say. Probably popping off the head is your best option (not fun).

Just out of curiosity, how come you torqued them to 80ft/lbs and not 72ft/lbs as per ARP spec?

I had a little piece of paper that came with the studs that said 80ft/lbs on it, so thats what I went to. Will the extra cause an issue?

Shutting down the engine immediatly from hot and checking the plugs should reveal which plug is being steam cleaned, though thats not a fool proof method, as steam cleaning requires some combustion to happen. If the cylinder doesnt fire at all, the plug will just be wet and smell of fuel.

The scope will only spot damage after its happened. Having water in your oil is good enough reason to pull the head off and check the gasket is covering the water and oil passeges properly. Your going to have to do it to fix the issue anyway, so why delay...

Did you do a test alignment of the gasket on the head and the block to make sure it covered the holes?

What kind of gasket did you use?

Was the block decked and the head re-surface before you put the head back on?

Tested the allignment of the gasket, and everything seemed to line up fine, no issues.

Didn't get the head or deck re-surfaced because it was a slapper. I know you're going to call me stupid, but barely checked the flatness of the surfaces. The Engine shop did say the deck was pretty good though. Or good enough I should say.

Mafia,

Did you do a compression test when it was cold and also after when it's warmed up?

Possibility the head isn't torqued properly as well, hard to say. Probably popping off the head is your best option (not fun).

Was still fairly hot \ warm when I did the compression test. Want me to do a cold one? The plugs are still finger tight. Ready to test again.

The head isn't that bad to remove, dropping the turbo off the manifold to the side, disconnecting the inlet pipe, and unplugging the injectors, IAC and the other IAC \ control thing. Then just a matter of dropping the coolant and then cam covers, head bolts, and someone to help you lift it off.

Now, here is a problem, and most of you are probably going to call me a retard (I give you permission to lol).

I realized that I forgot to put in those 3 little bolts. You know. The pricks that are a complete ass to get to when removing the head. And One would think that these allow more seal on the oil drains on the front and back of the head. Water is there too. And since they are oil drains, there is no pressure, and then allowing 13 psi of water into the oil. Probably not much, but enough to create havoc.

*Cowers and waits for the insults*

Edited by The Mafia

You should pressure test the cooling system cold, then warm the engine and do it again.

I wonder if not having the fastners in there is alowing the head to move away from the block (when warm) enough to cause the leak?

Mafia,

Any chance you can put together a list of parts and where you purchased them for the slapper? I'm considering doing this soon as I have just scored a few RB30 Blocks. Not sure if i'd go as far as re ringing and doing the bearings tho for the first block. Second block will be used for a slow build up.

If the paper said 80ft/lbs then thats cool. Unless you used the higher torque from the next grade of studs... Either way I cant see it being an issue.

You probably should pull the head and then clean the gasket and apply hylomar to it and retorque it down. As GTRNUR said, hymolar is fantastic stuff. I've reused the same headgasket three times without any issues :)

Don't beat yourself up for having a go. There are many that wouldnt have gotten as far as you have already, and nobody gets their first engine 100% correct.

A standard graphite syle head gasket will tolerate up to 0.007" of surface variation. Chances are the block was fine, but the heads are rarely perfectly square. The head being alloy tends to take on the distortion of the head gasket and block it was previously bolted too. Its called bruising, and is the main reason heads are shaved, so as to produce a dead flat surface to mate to the block. Having said that, a good coating of hylomar spray on the head gasket would have also guaranteed a seal. When you do re-fit the head, you should give the gasket a good 3 coats a side letting it tack off between coats, so its got an even shade of blue.

The head stud torque will be fine, provided the block was torque plated to the same torque when the finish hones were done. So long as the bolt torque is at the recommended tension, and under the yeild strength of the bolt it will be fine. The blocks hold a hell of a lot of tension. The 1/2" studs in my engine are torqued to 110ft-lb.

thanks GTRNUR. I appreciate your input.

Does anyone know if those 3 little bolts will make all the difference?

I'm thinking of biting the bullet, and just pulling the head - Its might be a "defeat in detail" kind of approach, but I want it to be fixed 100%, and no more guess work.

If I pull the head I can check:

The grub screw

The bores

The gasket (And replace with heaps of hylomar spray)

Install the three little bolts

etc etc

I might even use my spare head - Prep it out of the car, and get it faced.

This "hylomar spray", is it like copper spray?

Hylomar is an ACL product, and its a non-setting high temp silicon base sealant. You get it from supercheap auto or autobarn. Cheap as chips and worth its weight in mur. The acl product is intended for use on copper head gaskets, much like the copper spray, but it is definatly not copper.

Also, I do have a cometic 3 layer 1.3mm head gasket but I was told the surfaces have to be 100% flat for that. So I bought the Durotek 1.3mm graphite with the fire rings.

Definitely couldn't use the cometic?

You normally need a pretty good surface finish to use a mls headgasket. Probably 40RA or finer. Usually with alloy heads/cast iron blocks and mls headgaskets, the finer the finish the better. If you arent getting your head faced, then probably best to not use your mls gasket.

GTRNUR will probably confirm this. After all his development work on his open deck stroker build he would be an expert in this area!

You normally need a pretty good surface finish to use a mls headgasket. Probably 40RA or finer. Usually with alloy heads/cast iron blocks and mls headgaskets, the finer the finish the better. If you arent getting your head faced, then probably best to not use your mls gasket.

GTRNUR will probably confirm this. After all his development work on his open deck stroker build he would be an expert in this area!

Yes I confirm this! I wouldnt consider an MLS gasket unless both surfaces are machined dead flat. Some machineshops use different tooling to shave/deck heads and blocks too. Its worth asking around to see who can do the best surface finish to the highest tolerance. Or just o-ring the cylinders and use a standard gasket and its even better than an MLS gasket.

Not really related to your post but... did you just follow the RB30 guide here on the forum to build your engine? Was there anything missing? I'm considering an RB30, but up til now, biggest job i've done is installing a turbo :P but i have mechanically minded friends who could help

I doubt those 3 little bolts would be an issue, recently when I took off my head on my rb25det I found whoever previously touched it they only put one of those small bolts and didnt put 1 head bolt and I have driven it around for about 100000 with alot of thrashing and the gasket didnt leak or blow.

Ok, so the head has been removed.

Here is the Verdict:

- The Exhaust cam cover at the back was all sludged up with a caramel looking oil \ water.

- The cams were a little sludged up

- I did actually install the two rear little bolts. The front one wasn't installed.

- The head gasket looked like it wasn't sealed properly where the VCT feed is (and grub screwed).

- The bores are still like new and have very prominent hone marks thank f**k.

- Seems the head gasket was the issue all the way, leaking into an oil drain

Resolutions:

- I will check the flatness of the head

- I am thinking if the head doesn't need to be surfaced, I will Defcon the grub screw in to make sure it doesn't leak.

- If the head needs surfacing, I will get the grub screw removed and weld up the head.

- Might look at adjusting the head gasket to suit the gallery a little more

- Will make sure that little bolt at the front is done up nice and tight.

If anyone has anymore tips, I would appreciate anything you can give me.

Thanks again for all of your help here.

GTRNUR was right on the money, thats for sure.

Glad you caught it in time.

I think you'll find a re-surface and some Hylomar will solve all your woes.

Are you planning on doing a full tear down and re-assmelble, or just re-doing the top end? If your going to try just re-doing the top end it is still worth pulling off the main cradle and having a peek at the main bearing journels. Have a look at one or two rod bearing journels as well while your at it. Just so you can restore your confidence in the engine.

  • Like 1

A light spray of Hylomar regardless. Never had an issue doing so, once had an issue not doing so.

And face the head its only $40-50, they give it a bath that will clean all the sludge and crap out of it.

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



  • Similar Content

  • Latest Posts

    • Thanks everyone for the replies and suggestions. Got the seats out (hoping I could find some existing grommets but no such luck). By tapping and measuring etc. I could figure out where I could drill through if needed. But first I borrowed an inspection camera and managed to go through factory holes in the chassis rail and could see that the captive nut was holding steady which is why it could retighten. So it was indeed a stripped section of thread, so I applied downforce by levering the bolt head with a screwdriver and went slowly back and forth until it came out. Camera helped a lot cos I could monitor that the captive nut was holding tight. Now I just have one very seized main subframe nut to tackle 😅
    • BOVs do have a purpose, if you ever log pressure before and after the throttle body, you will see a spike pre throttle on lift off from a WOT condition. Enough to bend throttle blades / damage e-throttle motors or simple assist in blowing off cooler pipes. FWIW, the above on really applies to those running at least 2 bar of boost. OP shouldn't have an issue, on the other hand, here are some videos of my shit box over a decade ago with some succulent dose with the airbox on and off. That shit box is unrecognisable these days 🫠    
    • I've tried all different combinations of BOVs/ no BOV and stock bypass valves over the years, on gear changes the stock bypass valve seems to get the car back on boost quicker because in part the turbos wheel speed isn't being slowed down by reversion, although they have issues holding boost much over the stock setting. Most aftermarket BOVs you can adjust the spring, tighter will make it open later and close sooner, but in my experience it'll cause a bit of flutter at low load/rpm anyway. I've also got some input into this whole no bov causing turbo wear, never had an issue on any on my turbos HOWEVER, I got my R33 GTST with 200k kms on it, with from what I can see still has the original turbo, no lateral shaft play but has about 4-5mm of play in and out which to me seems like a worn thrust bearing from years (100-150k kms?) of turbo flutter running no bov, so maybe there is some truth to it in the long run. But that'll never stop me loving the Stutututu while I have the car.   OP just wants to know if he can run a atmo vented BOV with no major issues and the answer is YES, plenty of people do it, there's no harm in installing it and seeing how it runs before spending $$$ on an aftermarket ecu, last time I bought a Nistune it was $2400 for install and a tune , unsure of todays prices but you get me. Crazy money to spend just to fix the minor inconvenience of stalling that can be overcome by letting the revs come down to near idle before putting the clutch in or a little bit of throttle to avoid it. You're better off leaving the ecu and tune for after a bigger turbo/injectors have been installed to take full advantage of the tune and get your moneys worth.   Let OP have his Whoosh sound without trying to break his bank haha
    • I see you missed the rest of the conversation where they have benefits, but nothing to do with avoiding breaking turbos, which is what the aftermarket BOV made all the fan boys, tuners, and modders believe was the only purpose for them...
    • But they do so for the other reasons to have a compressor bypass. It's in the name.
×
×
  • Create New...