Hey guys, I just got a 2003 disco. 9 engine codes and the 3 amigos. Mostly misfire codes, replaced coils plugs wires, etc. put back together and still threw codes. Decided to tear it down farther. Have the heads off now going to do gaskets and seen somewhere it could be a burnt valve. when i pulled the heads off 4 of the 8 new plugs were black. Im going to clean up the heads, replace push rods valves springs etc.They're pretty bad looking. My main question is are these valves adjustable? Doesnt look like it, if so how do you adjust them? Ive replaces everything i could think of so far. Never had anything tore apart this far, just trying to gather some advice. Thanks!

 

What codes were you getting?

If you are doing a head gasket job you need to get new Head bolts as well. If you order the head gasket kit from AtlanticBritish it will come with all of the new seals and gaskets to put your engine back together (minus the head bolts). You should really take the heads to a machine shop to get cleaned and resurfaced and they can put the new valve stem seals from the head gasket kit on for you.

Can I ask why you decided to replace the springs and pushrods? Unless the pushrods are bent they should be good. Make sure that you put them back into the same place they came from and the correct ends facing up and down.

 

I dont have all the codes with me but the ones i remember were po301 po304 p1300 and a few more. The reason for the springs and rods is they look horrible. I will try to clean them up but they are covered in carbon build up and burnt oil and i figured while everything was out of the vehicle would be a good time to replace. Do you know if the valves are adjustable? Thanks for the help

 

See pages from RAVE attached. Hope you have been using RAVE. This is an old school 60's motor design, hydraulic lifters were used to avoid solid lifters and the valve adjustments that came with them. Having a machine shop handle that will save time and eventual money if you make a small mistake on it.

 

I would wait to get new springs and pushrods unless they are bent or broken. Below are some before and after pictures of my heads when I did mine. As you can see I had really bad carbon build up also, but after they came back from the machine shop they looked good as new. I can assure you that you will never be able to get your heads this clean on your own at home. If you want to do the job right then take your heads to a professional to have them cleaned, resurfaced and a valve job done.
Do the job right once, or half *** it and redo it in a few 1,000 miles. (If you make it that far.)

 

have the machine shop "hot tank" the heads

 

I agree with what has been mentioned and would go a set further, pull and inspect each lifter and cam lobe fore wear. Use my sticky at the top of this section on what to do and look for when dealing with head gaskets and valve trains.
Also, in the future, always keep your fault code numbers and list them when you are describing an issue, makes it easier for us to help you.

 

once you get it back together start running 15w40 rottella oil, to help clean out the oil passages in the block.

 

Can't say if it works, but for a day or so before I do an oil change I dump a can of seafoam into the oil.

 

Whoever had your truck - may have changed the oil 5 times.
It was really really gunked up.

I bet your lower main bearings and crank bearings should be inspected too.

I would do an oil pressure test.

There was so much build up - it goes toward abuse.

I would run thin synthetic to get all the junk out.
Or try the Seafoam..

Problem is - once that stuff is loose, it may get into oil passages and lifters.
You should pull your oil pan and get all the crud out of there.
There has to be tons of it in there.