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elitejaso · Joined: 24 Jul 2007 Posts: 143 Location: Melbourne

Ok after fixing my exhaust, adjusting timing and replacing a few hoses the car has been running awesome as my daily driver.

However one day after coming back from work i noticed a white cloud of smoke pouring out of the exhaust.

Once at home i noticed that the coolant was dissappearing quite rapidly and been blown out the back of my exhaust and smelt of burning coolant.

I quickly assumed that the head gasket was stuffed and with the spare time i have had this week i have worked on taking the head out to access the damage.

I thought i'd be smart and instead of pulling the whole engine out and then remove the head i decided to try and take it out whilst still in the car.

Well lets just say that after many hours of swearing, broken tools and heaps of cuts and bruizes i managed to lift the head up enough to pull the gasket out.
Was going to pull the whole head out but a bracket was getting wedged and i've decided to pull it out onto the bench 2moro (need a fresh mind as i was going insane).

Anyhow to my dissapoitment after studying the head gasket it seemed fine and there was no way coolant was making its way into the cylinders.

So at the moment i was wondering if i most likely have a cracked head (which i hope not) or is there something else going wrong that i might be missing?
Whilst working under the car i also noticed i little bit of coolant leaking from the turbo, could this be the culprut?

Any help or guidance would be greatly appreciated.

I'll have the head out 2moro and if the cam works i'll take photos and upload them.

Also just a few other queries floating in mind while they're fresh.
Are the bolts that connect the head to the block meant to be torqued up really really tight as mine were a nightmare even with a huge wrench.

Thx guys

Rich H · Posted: Thu Jul 17, 2008 11:35 pm Post subject:

Loosing coolant and white smoke means head gasket, cracked head or cracked block...

_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

In my experience, you cannot judge the condition of the head gasket from a visual inspection. I had a blown HG on my NA, and when I pulled it, it appeared fine even though it was definitely the culprit.

Once you get the head out, check it thoroughly for cracks. Might even be worth taking it to a shop to make sure it's not warped (which would be an indication of previous abuse). If the head is not cracked or warped, it would be highly unlikely that block would be cracked (although not impossible).

The turbo is not water cooled, so coolant could not be leaking from it. More than likely, it was either the head gasket, or perhaps one of the front-of-engine coolant hoses or the thermostat housing gasket that let go, which might cause coolant to run down in the area of the turbo.

Good luck, let us know how you fare.
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erstwhile owner of just about every 924 variant ever made

elitejaso · Joined: 24 Jul 2007 Posts: 143 Location: Melbourne

Thx for the replies guys
I hope its not a cracked head or block that would be a real pain

Anway, this arfternoon i attempted to pull out the head again but this stupid bracket connecting to the block and an oil line are getting wedged and i've given up and am pulling the whole engine next week. Witht the engine out it'll be alot easier for me to assemble it all back together.
Just wondering if these engines are pulled from the top or thru the bottom. It seems it would be easy to just drop, what do you guys recommend?

Whilst i was trying to lift the head out i noticed another head gasket and a spacer between the head and the block. Thats right for some reason my car has two head gaskets with a spacer in between. Is this normal for an 81 932?

I'm guessing the spacer is their to lower compression or somethin and then 2 gaskets are required but this cant be stock can it?

I've got some photos of the head gaskets and spacer i pulled out (sorry the light was bad and its hard to get a good look at em).
I think there might be a breach on the second head gasket on the last cylinder.

Any got any ideas about my gasket setup?[/img]

morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

wow !
it might be that some PO shaved the block so much and then tought...oh wait...thats not right is it? and put this stuff on...
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tuurbo · Posted: Fri Jul 18, 2008 8:57 pm Post subject:

Wow a spacer sandwich. Never seen that before.

I'm no expert but it looks like your diagnosis problem is solved.

Might want to hold back on pulling the engine?
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1980 924 turbo, MSD, Meth. Inj, otherwise stock.

924guy · Posted: Fri Jul 18, 2008 10:47 pm Post subject:

wow... I would definitely want to have the head checked. check your slugs as well, see if they've been replaced with after market pistons of some sort. theres gotta be a reason for the gasket sandwich, and none i can think of are good...

But hopefully it was just some rocket scientists idea of an "upgrade" with no other reason, it happens on occasion...

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Eric
78 924
82 931 SE "smokey"
99' VehiCross
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924turbo_sout_africa · Joined: 29 Oct 2007 Posts: 215 Location: Sout africa

ok ok ...well i have almost the same thing om ym race car ...i had the head skimmed off by 2mm and found the compresion was to much 15:1 ratio is what they worked out so i kept breaking pistons,they then made a thick gasket of about 1.5mm and problem solved .

moral of the story is if that is the same in your case too high compresion from tto much skimming then get a place to make you a headgasked that will be thick enought without having to use a spacer.
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Porsche ...where dreams are a reality
'79 924 turbo canada spec
'98 Formula Vee (M3 eater)

Time in the 931 is a dream come true !!

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Fascinating! It will be interesting to get to the bottom of this enigma for sure!
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erstwhile owner of just about every 924 variant ever made

elitejaso · Joined: 24 Jul 2007 Posts: 143 Location: Melbourne

Just a quick update,

Have disconnected everything from the engine such as electricals, hoses etc and am going to pull out the engine 2moro.
Just need to drop the crossmember and take out the bellhousing bolts and it'll b out in no time

Then i can examine the head and get this problem solved once and for all.

Heres i pick of the engine before it comes out

My top mount mazda intercooler also arrived today

however it looks like my gt intercooler project will obviously be put on hold for now.

Also decided to completely clear the engine bay area and paint it red (probably guards red) for the future gt transformation, might aswell get it done while the engines out.

Thats it for now, i'll keep you all posted

elitejaso · Joined: 24 Jul 2007 Posts: 143 Location: Melbourne

Ok, got the head out today and you can definately see where the water has breached into the second cylinder through the headgasket.
Now that i have the problem identified i still have the bigger problem of this, quote from tuurbo "spacer sandwich".
The geniuses before me had shaved of 3mm for whatever reason (i suspect drinking on the job) and therefore came up with the two gasket idea.
Now this is where i'm stuck, turbo heads are hard to find here in australia and it'll be hard to find a decent one that doesn't cost more than what i paid for the car.
924turbo_sout_africa came up with the thicker head gasket idea which i think would be a good fix but these gaskets seem complex and for a shop to make one up who knows what they'll want.
The other option is of course just putting in one brand new gasket and hope for the best

What compression do u guys think 3mm of the head would be increased to from the original 8.5?

Any thoughts or comments from you experienced guys will hopefully help put me in the right direction.

Cheers Jason

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Bear in mind, higher compression on a turbo car is not necessarily a bad thing provided you can do a proper job of thermal management. I see you're already looking at an intercooler. Once you figure out the CR, you might think about just going with a stock gasket and managing your boost & intake temps accordingly.

The other factor, of course, will be timing. There are many other discussions here on the board about the affect on timing when skimming the head, so some creative searching is in order. At minimum, an adjustable cam gear is probably a very good idea, or you might see if you could convince "bass gt" to let go of one of his two Franco variable cam gears.
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erstwhile owner of just about every 924 variant ever made

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

Pretty interesting problem. How do you know it was shaved 3mm? I assume this was off the head or was it the block? You will need to measure the combustion chamber volume in order to calculate your compression. If you do go with a higher compression you might also consider a programmable ignition system to better control timing.

Todd
_________________
'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

924turbo_sout_africa · Joined: 29 Oct 2007 Posts: 215 Location: Sout africa

to be honest men ...i took about 2 or 3 mm of my vw 1.8 litre motor and well i have 4 set of pistons broken from too high a compresion ...my mechanic at porsche who has a turbo himself said you can push the cr to about 9 safely but anymore than that he said be sure to be looking for other pistons so be carefull with the compresion ...i'm sure if you ask around you will find a place to make the gasket ....mine cost R250 now that is not expensive and i'm sure with all the racing in oz there must be a place that side to fabricate you 1
_________________
Porsche ...where dreams are a reality
'79 924 turbo canada spec
'98 Formula Vee (M3 eater)

Time in the 931 is a dream come true !!

elitejaso · Joined: 24 Jul 2007 Posts: 143 Location: Melbourne

Thx for the replies guys,
Just to clarify they shaved 3mm of the head which is why they put in 2 gaskets and a spacer. Also explains why the head was torqued down soooo tight.
Anyhow calculated what the cr would be with just one gasket and it comes to 12-1 so i guess thats outta the question. I dont really wanna be changin the pistons over every week but just imagine the acceleration

Well so i'm either gonna buy another gasket and stick with the previous 2 gasket setup or get one thicker gasket made up. I'll call up a few shops this week to see who can make 1.
At the moment just cleaning everything replacing gaskets and a few hoses.
Hopefully the car will be back on the road in the next few weeks as i do miss it.

Keep the comments and ideas coming, i'll keep you all posted