Looks really good. I am getting ready to do this to mine tomorrow night and finish up Sat. Advantage I have is I am a professional mechanic. I did a set of Disco 2 headgaskets without even looking at the rave.

 

Good luck to you ColoDisco, I stripped a thread in my head last night trying to get the exhaust manifold on so just be sure you have a helper to hold heavy things up and finger tighten everything! Don't force anything.

 

Seeing the pictures makes me want to learn more about the specific internals of these engines.

Sorry to hear you strip the threads in that hole. How bad is it? Can they be cleaned up by running a tap in there? They do make a special tap for cleaning up minor damage, I don't know what they are called. If it bad enough, I think you also have the option of a helicoil insert. I do not know enough about the subject to offer any specific advice, maybe others on here can help out with a solid solution.

 

@Danny Yeah I thought it was stripped but it was actually the exhaust manifold being difficult and not lined up perfectly, the screw was going in at a slight angle. with a little encouragement it went in aka a socket. Putting the front back together and the top then the puzzle of connecting all the wires and hopefully *Crosses fingers* a successful start up! Nervous!!!!!!!

 

Oh btw it's called a tap and die kit. It's not that hard to do but does require some thinking. It's not that big of a deal though if you do strip something just need the kit

 

I always start nuts and bolts by finger. I have cross threaded too many times as a result of "screw it! just run it in!"

 

The mission was a success fellas! The disco started up tonight and I will finish a detailed write up tomorrow! Very happy with the job!

 

Machined Heads ($440), Tools I didn’t have ($100), Fluids…yes beer counts($70), Gaskets & Bolts ($180)….. Performing successful open heart surgery on my 94 Discovery… priceless

Total length of project: ~3 Weeks (this was working on it two or three times a week for 1-2 hours) So approximately 12-15 hours

Thank you to everyone that contributed to this project! The resources online are unbelievable and I encourage anyone attempting this job to read as much as possible before they perform it.

So before I get into the problems I ran into let me first go through the most useful tools and equipment I used on this project:

• In search of the experience DVD – this DVD includes a pretty thorough explanation of the entire procedure and covers all of the common questions asked during the job as well as much much more. I strongly recommend this DVD to anyone that has to do this job and is not a practicing mechanic.
• Breaker Bar aka the tire changing pipe in the set that comes with each Disco
• Bottle Jack – I love this jack more than anything, was useful for the exhaust removal and refitting.
• Pry Bars – bought a set of 3 different sizes, extremely useful to get those hoses off
• Camera – I was nervous about unplugging every wire and pulling a lot of the hoses off but it was reassuring knowing that most of the connections were documented and were there for reference. I marked nothing while taking things off though, everything goes back together pretty simply if you just use some common sense.
• Swivel adapters – instead of buying a huge set of swivel set sockets I just bought the adaptors that turn any socket into a swivel.
• Torque Wrench – friend lent me his, crucial.
• Magnetic pick up tool - figure it out haha
• Gold sharpie – for marking head bolts for the 90* rotations
• Right Stuff – the best RTV out there
• Rail of Sockets – both SAE and Metric, obviously a ˝ inch drive ratchet wrench for them
• RAVE – gotta love it
• Fan clutch tool – just for taking the fan off
• Brake parts cleaner – different from carb cleaner and stronger, probably went through 10 cans or so, my car was filthy.
• Ziplock bags – place all your bolts in them and label them specific to the parts they go to, made assembly so easy and felt great throwing them away

Specific sockets needed –

• 12 point 5/16th – the valve/rocker covers require this
• long 13/16th – spark plug removal and placement
• 5/6 – Invest in an impact socket for this because this will be used for the head bolts
• Socket extensions – so incredibly valuable

Things replaced -
Head gaskets obviously, valley pan gasket, valve cover gaskets, water pump gasket, distributor cap and rotor, wires, fluids, valve seats, exhaust manifold gaskets exhaust manifold to down pipe gaskets, spark plugs, fan blades and radiator cap (you’ll read why below haha)

A general summary of the steps I took
1) Take apart top of engine up to Air box and Plenum (Hex bolts)
2) Drain coolant
3) Take apart front of engine, Remove fan, front of water pump (didn’t remove the whole thing and left the distributor in there also, Power steering fluid pump, alternator, tensioner, Ac/Heat pump. The Ac/heat pump is on the same bracket as the alternator so I only removed the alternator and left the bracket in the engine bay so I didn’t have to deal with unscrewing the AC hoses.
4) Take Exhaust manifolds off
5) Take heads intake manifold off, take heads off
6) CLEAN EVERYTHING, machine heads, valve jobs, all mating surfaces, pour a quart or two of cheap oil into the engine just on top of the cam shaft to pull any nasty stuff down.
7) Torque down heads, valley pan, intake manifold, end clamps, rockers, valve covers, exhaust manifold, plenum, front of engine, air box/MAF, fan, oil change, coolant, plugs and wires, battery
8) Check for no tools in engine bay and secure anything small around that might fall into engine bay.
9) Pray.
10) CRANK THAT ****TTTTTTTTTTT
11) Cry out of happiness
12) Check coolant levels, bleed system
13) Change oil in a day or two after driving

Problems that were faced and defeated:

Brittle wires and plugs – In a 94 everything you touch will fall apart, you will not be able to find a new wire harness easily so be nice to your current one or you will end up with ripped wires and a sad face

Gross engine – power wash the bottom of your car before you do this job it will make things much cleaner and you won’t be crying when dirt goes in your mouth and eyes.

Firing order Sequence/diagram – Make sure to take note of your original sequence before you remove your wires. The one I saw online as well as in the Rave were both incorrect for my model. I found one on page 67 of the RAVE for the 3.9 and it made everything turn out beautifully.

Exhaust manifold not lining up – When placing the exhaust manifold back on I suggest removing the manifold from the rest of the exhaust for two reasons. You can replace the gasket in the connection there and you can handle the exhaust manifold much easier after that. Oh and you can check for cracks in your exhaust manifold which is a common problem in our cars. One hole in the manifold didn’t line up exactly once I began screwing in the bolts. Make sure you screw everything in finger tight before you start using a socket wrench, if you feel resistance use a socket but only if are sure the bolt will not strip the threads.

Useful tips:
The bottle jack was very handy for getting the exhaust back in place, push it in between the exhaust and the body of the car and maneuver it which ever way you need to

Torque sequence is 15nm then 90 degrees then another 90 degrees as per rave and head gasket directions

Write down torques for everything before you begin

Intake manifold is the only other thing that has a sequence to it

Have a friend there, not only is it reassuring knowing that someone is there to help you lift the heavy bits its also daunting to do this alone so a friend really helps with the encouragement.

Place everything in the back of your truck and try to be as organized as possible. An organized work area will lead to a well done job! Keep your radiator fan vertical also, I’ve heard so many things about the fan messing up if laid down…

Another very well done write up: http://www.discoweb.org/forums/showt...ferrerid=18051

Summary:
All in all the job was a lot of fun! Spreading out over a few weeks time made it much easier to do, you could get it done in two days if you really set yourself on it. Looking back at the entire job I regret nothing and saving a $1000 really feels good. Especially now that I know I can fix anything on this discovery. Thinking about the job now and how loose everything was (especially the head bolts) while taking it apart I don’t believe that the head gasket was the direct cause of my coolant leak. It seems that having a loose bolts doesn’t do wonders for an engine. Everything works beautifully now and the engine runs smoother and quieter than ever. So no cracked headbolts, no stripped threads, no broken fingers, and no major surprises. How can a head gasket job go soo smoothly?!?! Well there was one hiccup. Right before we started the car up we removed the radiator expansion cap and placed it right on the top of the radiator. When the car started up the cap rolled into the engine bay, hit one of the fan blades, shot across the garage, the fan blade broke off and lodged itself in the serpentine belt, which lead to a very loud squeaking noise. It took us a minute to piece together what happened but everything and everyone is okay, just have to replace those two items now. Watching the video again I actually don't see the cap rolling off the engine so... Idk where it came from but it was certainly the cap Extra $41 from Will Tillery aka RoverGuy! We got a video below of the incident you guys will appreciate it haha.


Good luck to everyone that is doing this job! I can repost this if we want to make a sticky for head gaskets under the D1 section. Pictures of the incident, final product and some helpful diagrams below...

The video, Couldn't figure out how to post it...