How do I know if I've done a head gasket?

[Quiggers]

How do I know if I've done a head gasket? I have a few concerns. It's a 3.5 V8 in a Discovery 1 (1993). Any thoughts would be greatly appreciated. Thanks guys.

[Reads90]

Originally posted by Quiggers
How do I know if I've done a head gasket? I have a few concerns. It's a 3.5 V8 in a Discovery 1 (1993). Any thoughts would be greatly appreciated. Thanks guys.

well the most common is the gasket to go across the water and oil ways. So look for oil in the water . This may be found buy an oily scum on the top of the filler of the reserve tank for the rad. Will be what we call cafe cream. a beige coulr stuff that will sit on the top. This is oil and water mixed.
While you are there the other thing to check is if you can smell petrol in the water as this means the gasket has gone from the water to a cylinder.

The other check is to start it up and take of the oil filler and she how much it is Chuffing. This means pumping air out of the oil filler.If it is bad it will look like a train and chuff. This means the oil way has leaked across to the cyinlder. so send the exhaust gases into the engine. But it could also mean that your piston rings are gone, as it does the same thing then

Why do you think you have a head gasket gone

[George130]

You can get your coolant tested for exaust gasses. $22 by NATRAD. Other places will do it also. The test kit is $100 from repco If you want to buy one and do it yourself. I'm in the process of testing mine at the moment.

[Quiggers]

Thankyou gentlemen.

reads90: I keep blowing hoses. (and the heater matrix). I have replaced all, bar the bottom hose, which is leaking at the t joint. (The replacement is on the way courtesy of our abovementioned advertiser).

Also, I've been around engines (bit I'm not an official mechanic) for a long time and it just doesn't seem right.

It's not blowing smoke and it runs real well for a motor with 270,000 ks (country ks too!) I've run hot a few times, but not to the point where the warning light has lit.

Went thru a drama with the X1/9 years ago which took four head gaskets before the problem was solved, the original head was porous, but I only discovered this after some time, good thing that FIAT headgaskets are cheap and easy to replace.

The long and the short is: the donk is great, but something is amiss.

george130: pressure testing the water system, do you think this may exacerbate a minor problem? I don't really want to change donks as this one works but leaks... but i've probably answered my own question, when the new bottom hose goes on, all will be well....hmmmm).

Thanks guys and will report when the new bottom hose is fitted, mungrel of a job....

Cheers and thanks, GQ

[George130]

The pressure test will show your current leek but the other one is a chemical reaction between the test fluid and anything comming out of your radiator. I had the pressure test done today and everything went well. Tomorrow I am having the chemical test done just to be on the safe side.

[DEFENDERZOOK]

<span style="color:blue">pressurise the cooling system and let it sit for about 10 mins with pressure in it....
in the mean time...remove the spark plugs.....
and disconnect the power to the coil....

after 10 mins get someone to crank over the engine and check to see if
there is any water shooting out the plug holes.....

if all is ok......
then you need to bring each cylinder up to compression stroke....TDC....
one at a time of course.....
and make up an adapter from an old sparkplug with the porcelain removed
and an airhose fitting welded on.....
screw this into the sparkplug hole and connect an airline to pressurise the cylinder....

safety warning...it is possible that the compressed air can push the piston
down and spin the engine...so try and chock the flywheel or crankshaft
pulley...and keep hands well clear of any moving parts....

all you need to do now is check for bubbles in the cooling system....
and being a V8...you will only need to this 8 times....(should only take a day or two...)

try the first method first.....(and dont bother with the second.....)



if the heads do need to come of......get the valves re-seated....or at the minimum
have them lapped in....
these things never sealed properly from the factory.....i remember ripping the heads off
V8s on the pre-delivery inspection and getting the valves lapped to get them to idle smooth....
worked a treat......and they ran better too.....</span>

[Quiggers]

geez zook, time to get out of neutral bay come up here for a break and do the job.....!

seriously tho...

i may be wrong, but i may not be, but some years back i had the donk compression tested on the old ED Falcon, this was done by a mechanic, who blew the electronic stuff, cost him a replacement dizzy and computer,

i did some research on this later and from what i found the computer likes to talk to all the spark plugs, so traditional style compression testing worries me...

love your reply, tho. kinda looking forward to trip back to the old home, should have kept the house in carter street, I'd be worth more than kerry packer, yuk yuk.

cheers and beers, its bloody hot up here, even at 10.30pm. GQ

[DEFENDERZOOK]

<span style="color:blue">thats why i said to disconnect the power from the coil......
some mechanics use old school methods and just earth the coil lead to prevent
all the sparks from flying around.....a no-no with electronic ignition.....




where abouts in nsw is alstonville.....?</span>

[JohnE]

Just up down the road from Tregeagle.
or as all the marketers around here say 'near Byron Bay'
I 'll let you know if his pub is okay.
I am going there this evening.
john

[Quiggers]

It's not okay, the pub that is, but it's close. It's not even a pub. it's a tavern and was built about 15 y ago. Similar to a prefab concrete factory.

Alstonville is about halfway between Ballina and Lismore on the Bruxner Highway. About 750ks from the Oaks.

Cheers, GQ.