924Board.org

[DeadPurple]

I found water in my oil today, that and I either have a cracked head or bad head gasket.
Abyone know how much it and where I can find these parts?

[8trdrvr]

Purp,

Yikes, sorry to hear that man. The head on these cars (stock) as i gather are very strong heads, i doubt you have a cracked head. Im willing to say its just the head gasket.

the best thing the guys told me to do here is pull the spark plugs and run a compresion test, i learned a lot just from doing that with my mechanic. (he lets me watch:) and hand him tools ) i would recommend doing both of those. How bad does the oil look? does the coolant look discolored too? How about any trouble with starting?

I just brought my car into my mechanic to get the head done (last week), its gonna take him a week or so to do it. Pulling the head is really not that hard you may be able to save some $$ by doing it yourself then getting the car to a profesional for the rest. Putting it back together and the machine shop is what will cost you. heres what sucks and this is the expensive part... While the head is off you best get the valves reseated and cleaned and have the head 'baked' too. as long as you dont need new valves or valve guides you should be saved from major $$$. Mine will end up costing me around 500-600 bucks when its all said and done.

Good luck and let us know how you make out.

KeviN

_________________
ATR-42 Driver (EWR) -Runs on Jet Fuel
1982 Porsche 924 -Runs on mogas
First time Porsche owner :

[ This Message was edited by: 8trdrvr on 2002-06-07 22:50 ]

[Rick MacLaren]

Sorry to hear that. Don't despair though, it might not be crucial yet.

8trdrvr is quite correct, it's 'unlikely' you've destroyed the head if it's a '24. It's not terribly serious. Notably, depending on circumstances, you could take this as an early warning sign that your cooling and/or electrical system (i.e., fans, thermofan switch) are faulty and need upgrading or repair. It's not 'natural' to blow a head gasket.

IF you have a 931, or want a 931 head gasket, I have one in the package, shrink wrapped by Porsche, that I have to get rid of. Not looking to make money, just want to recoup some. So if you need, lemme know. Or if you just want to trade something. I have it in my car room at home and it's sitting there making me feel stupid for getting that and the gasket kit both from Porsche!

[MAD924]

Someone please tell me why you "need" to get the head "baked" and you "can't" have it "shaved". My head gasket was leaking about 5 years ago. I pulled the head, measured a warpage of .006" and then had it shaved .007". You can shave up to .015" before there is interfernce. I cleaned and seated the valves by hand. Everythings been fine since. And what is "baking" anyway?
And after you go thru the trouble of having your head done, put in a lower temp opening thermostat as well as a lower temp fan switch. There both cheap insurance to prevent overheating.
good luck

[Cbass]

I'm leery of shaving heads and blocks unless it's really necessary. It's a good principle to put new gaskets on a car when you get it, even better to really tear down the motor fully.

[8trdrvr]

Mad,
thanks for the good tip, i will do that. what parts exactly do i need? what will fit/work? are the both of them an easy install for a mostly thumbs guy?

if you can post the specifics about those parts id like to do that.

Kevin

[DeadPurple]

Heres the whole story
Driving home, noticed the meter jumped into the red zone. I was running it hot for about 3 miles to find a place to park. Pull into gas station with white smoke blowing hard out the exhaust pipe. Smoked filled the entire station. I was even asked to leave at first because of it. Ran water over it let it cool down. Noticed that the hose clamp was vey lose, hence why all the coolant had drained so fast. Car wont start. Tried even run starting it since its a manual, still nothing. Sounds like its about to crank but wont(you know that split second noise right before it cranks) So I was stranded.
OK, heres the amusing side of the story. Found this mechanic named Joe. Joe pushed the car to hus house and gives me a ride back to mine. Find out later that hes not really a mechanic just knows alot about cars. SO he fixes soem things, liek getting a tune up job. CHanges plugs, etc...
3 days go by and I hear nothing from Joe. I go over to see my car setting in his parking lot with hood open. Find out later that Joe has gone to jail for getting caught with crack. So I have my car as of right now being towed to some place that fixes exotic cars. Called one place and they told me that I had to take it there because its a Porsche. So now im waiting for the to truck man to call me back.

[8trdrvr]

Purp,

im sorry man, but that was a funny story... the whole crack part is what had me rolling. okay okay i'll be good now.

well after running it hot like that id venture to say you'll definatly need that head to get baked or milled. im far from a pro, just a victim here, need the pros to chime im here now, Rick, smoothie, go, ect...

the guy that works on my car is the dude that sold it to me, its one of those shops that only does european cars, im sure theres one nearby. just like one up from an everyday small shop.

let us know...
KeviN

_________________
ATR-42 Driver (EWR) -Runs on Jet Fuel
1982 Porsche 924 -Runs on mogas
First time Porsche owner :

[ This Message was edited by: 8trdrvr on 2002-06-08 00:59 ]

[Smoothie]

A couple of things I've heard/read (no first hand experience): 924 heads should be baked instead of shaved because compression can be altered and valve timing can be affected. Though I'd think you'd have to shave quite a bit to seriously affect valve timing - timing belts stretch some and that would have some affect on valve timing too... Also, it's not good to dump cool water onto or into any overheated engine. The rapid temperature change can crack the block and/or head. Have to let it cool down gradually before adding water, especially into the engine. I'd think there's less, but still a danger of cracking something by dumping water onto the outside of the engine. -And I'd guess an aluminum head would be less likely to crack from a sudden bath of cool water than a cast iron head - just a guess though. It's definitely always best to let things cool down before introducing cool water.

[gohim]

Most probably your head gasket is toast, and the cause was probably the overheating that occured when the coolant was lost.

It is not a good idea to run cold water over a how engine, especially if it has no coolant. It is safer for an overheated engine if you leave the engine running, and refill the coolant system, adding the water to the coolant tank.

Earlier 924 cylinder heads do have a tendency to crack (I think the ones more prone to cracking are/were the 77 1/2-79 model years. The earlier heads (not the earliest heads) have different shaped exhaust and intake ports. The cracking may be related to the fact that the cylinder heads that were more prone to cracking came on the 924 models that Porsche installed smog pumps on. Or, maybe not. I used to buy used 924 parts from a guy about 45 miles from here, he would take 924 and 931 cars apart, and sell the parts. The guy was selling cylinder heads on an exchange basis. He had a whole pile of 924 heads with cracks in the same places. The guy showed me the difference between the early, earlier, and late 924 heads. Only about 1 in 10 cracked heads were the late ones, the rest were the earlier ones. Of course, more 924s were made in the earlier years than the late years, and maybe that had something to do with the number of cracked earlier heads that he collected.

Porsche developed improved parts as time went on. The exhaust manifolds were a good example of this. The earliest ones cracked like crazy. Later production models cam with reinforced exhaust manifolds, and the eary cars received a revised replacement part with the same design of reinforcement ribs on the bottom, that the later cars received in production.

Your car probably won't start because coolant from the blown head gasket is shorting out the spark plugs, so they won't fire. Remove all four spark plugs. One, or more, will have coolant on them. Disconnect the coil wire, so you won't damage the ignition system. Use the starter to spin the engine, this will blow the water out of the cylinders. Reinstall the spark plugs immediately, the car should start, but depending on how badly damaged the head gasket is, the engine may overheat rapidly, and may dump all of the coolant quickly.

If you know what you are doing, you should be able to remove and replace the cylinder head in less than 2 hours. The "book" time for removing and installing a cylinder head on a 924 (the amount of time a mechanic will charge you printed in the labor time manual) is about 8 hours. That's $320 at $40 an hour, $640 at $80 an hours, and $1000 at $125 an hour. The cost of servicing the cylinder head is not included.

This is why it would pay you to get some tools and learn to do the job yourself. The last924 head that I had service to stock specs cost around $300 or $350 at the machine shop including all 8 valve guides, and 2 or 3 valves.



[ This Message was edited by: gohim on 2002-06-09 02:34 ]

[Cbass]

Apparently Eurorace sells a big valve model, with new valvetrain for $1000. I'm not sure whether it comes with a cam, or if they want a core.

[Smoothie]

Hey, Smoothie's learnin' somethin'. Good point - leave the engine running and add water through the expansion tank. -Keeps fans blowing and oil and whatever water's left circulating. Much better than letting that after-shutdown heat soak settle in and turn your head into a gravy boat.

[larso]

You can always boil your water in a kettle first and add it to your engine if it's hot, then mix it with the coolant. Definately not good to pour cold water into a hot head. Of course you might get kicked out of the kitchen when you are in coverals and try to steal a snack from the fridge with your greasy hands, while waiting for the water to boil...One thing I recommend when doing coolant changes are to NOT use the drain plug. They can round easy, as they are brass ( I think), and they can strip the rad easy. The rad is a aluminum. Instead of using the drain plug, use one of the lower rad hoses. The only thing about it is that the hose is quite big, so the coolant will come pouring out like an elephant taking a pee on you. Be careful. I feel a lot better using a hose though, because I know I will not strip my radiator! Another tip, is the thermostat...when buying a thermostat, always look for holes in the plate. If you install your thermostat, and it is closed when you are adding coolant, you'll end up getting air in the system very easily. It's wise to drill some extra holes in the thermo plate, but not too many. If you can't get the air out of the system, take the thermostat out, and pour coolant directly into the head through a funnel and hose.



[ This Message was edited by: larso on 2002-06-08 18:30 ]

[friskynibbles]

hey rick, do you still have that 931 head? i might need it (don't know yet)... what would it be worth?