another head gasket thread

[gimposarillios]

Iv got a 3.5 v8 disco1. My head gasket has failed badly, oil in the coolant and milky creamy gunk in my oil filler cap which i assume means coolant in the oil. Its also running pretty poorly.

Iv decided im gonna have a crack at fixing it myself (probably will turn out to be a mistake). Im looking for any recomendations on where to source the new gaskets and any thing else i would need, as well as any tips and tricks anyone can share with me.

Iv spent a bit of time searching this forum and have found some helpful things but i find that search function is a bit hit or miss (thats probably the way i use it though) so after around 3 hours i thought i might just start a new thread. Iv also had a good read of the rave.

Any help would be great

[bee utey]

Start it one morning, run it for 5-10 seconds, misfires and all, then turn it off. Then pull out the plugs and inspect for water and/or rust. If its the end plugs it's likely your tin head gaskets are stuffed. If there's water on the middle two plugs you've either got a cracked head or block (rare on a 3.5). New tin head gaskets are fine so long as your block and heads aren't warped at all. If you've run out of coolant and got it very hot, all bets are off. Have the heads checked for flatness and hardness before proceeding.

[xstriple]

Do you have tin or composite head gaskets? Cause I have a spare composite one if youre interested.

[Stumpy1]

Hi gimposarillios,

I have literally just finished rebuilding the top end on my 3.9l V8 due to blown head gaskit (cause was non opening thermostat... got too hot).

I too was in your position and had no idea where to start.

After many hours searching I stumbled upon 4wdparts on ebay. Gary was super helpful and though I'm in WA, I chose to do business with him over the phone and ordered a complete top end rebuild kit. The quality of the kit was exceptional and the parts turned up quickly and well packaged. His email is clr4wdparts@optusnet.com.au

I would not hesitate to use him again. My disco is now back on the road and behaving beautifully.

If you have average to good mechanical skills and take the time to be thorough and precise, you will not have to many issues doing the work yourself.

My tips.... 1) Take photos of the engine bay before you start. Take more photos after every major component is removed. I referred to these often to ensure hoses and wiring were properly located. 2) Clean everything and take care to clean up bolt threads etc. DO NOT REUSE YOUR CYL HEAD BOLTS! (unless you want to do it all again haha). If you are not sure, stop and refer to manual, ensure you tourqe bolts that need tourqing up as its very easy to over tighten bolts in aluminium.

Best of luck and I'm available if you have any questions..

[gimposarillios]

I determined it was a head gasket, thanks beeutey. I got my hands on a top end rebuild kit from clr (good tip on parts supplier stumpy1, they were great to deal with) abd have over the last few weeks had a crack.

So due to time constraints I only really have Sundays to work on the car and as it's not undercover, it's rain dependent so quite slow progress as well as deliberetly taking my time so I can keep a note on what Iv been doing and hopefully get it back together agai.

Anyway Iv been slowly pulling it apart hitting problem after problem. My big issue I haven't been able to solve is actually getting the heads off. After 20years they seem to have become one with the block. Any tips how to remove them or something I stupidly may have missed. Iv followed the rave procedure very closely.

So frustratrating. Thanks guys.

[bee utey]

There's a total of 14 head bolts per side. Missed some? Tin head gaskets don't stick, composite ones sometimes need a fistbump/rubber mallet or a hammer handle in one of the inlet ports as a lever.

[gimposarillios]

There my problem then. Thanks buddy.

[Stumpy1]

Hi mate. Hope you have had a win freeing the heads. Good point by beeutey. Easy to miss the last head bolts closest to firewall. Also, when giving them a bump with the rubber mallet(or hammer on block of wood) try to make sure you tap in a vertical direction as there are locating dowels between block and head. Go gently, don't get frustrated and if you do walk away and kick the cat or similar.

By the way, make sure you take the heads to an engineering shop and get them skimmed so they are perfectly flat when they go back on. It cost me 70 bucks a per head and with a good (but careful) cleaning of the block surface, it will ensure that the new head gasket will seal perfectly. I have run around 10 tanks of fuel through mine now and though I have noticed a very small power gain from the freshen up, it's the extra 60 km per tank that makes me smile!

Good luck and keep us up to date!

Stumpy

[gimposarillios]

Finally got the buggers out. there was a semi stripped bolt on the exhaust stopping me removing it and blocking a head bolt. 3 hours later and it was out. There was a fist pump when I got it off.

Now to find a cylinder head shop to check them out for me.

Thanks for the help so far, Im sure ill have several other questions trying to reassemble everything again.