Depends. There's that word again.

The cylinder is basically an air pump. If the intake valve isn't opening correctly at the right time and sealing then it won't build pressure. The exhaust valve also needs to seat correctly.

On the thermostat leak, I had the same problem. I ended up replacing the thermostat (has an O ring) and the neck. Problem solved.

 

Hmmm... the rubber seal that goes around the rim of the thermostat should suffice. If memory serves me correctly, it has a small tab which you use to orient it correctly. If you're doing all that and it still leaks, I would try using some gasket sealer on the surface. Mate the parts, finger-tighten, wait to dry, then torque. Really shouldn't have to do that though.

 

This is probably the only picture I need to post.

6QvQj6u.jpg

So this is a head replacement + timing chain replacement + god knows what else.

Possibly cheaper to get a new engine and install it. I could do THAT myself, at least.

 

Well after sleeping on it, and doing some pondering today, I think my options are as follows:

Pay a lot of money to have it serviced. Two people I have talked to seem to think it'll be north of $2000 to have this fixed, possibly in the neighborhood of $2700 - $3k. They both agree that it probably needs a new head, headgaskets on both, and a timing chain service; just the parts are around $1300 from what I googled. This is not something I feel is within my capabilities.

Just replace the single head and headgasket (along with misc. sundries), and re-time using existing chains. At 140k I'd think the chains should be OK? Will probably still cost well over $1000. Not comfortable with my ability to do this properly, either.

Buy used engine and replace. I could do this. Maybe even swap up to the 2008 model year 300hp 4.7l if I felt wild and crazy...

 

You need a new head, no way around it.

The timing chains are rated for 250k. I wouldn't bother with that, yet. Check out some boneyards for heads, have them refreshed, and put them on. If you can do the work - great!

4.7's aren't cheap.

 

So you think replace both heads?

 

You can just do the one head. You can get rebuilts online or just check your local u-pull. http://car-part.com might help

If you do it yourself make sure to set the timing for #1 TDC before you pull the head.

It does look like #2 is the one that pooched.

 

OK, thanks everyone. I'll update when I make any more progress. I may just have a local shop do it.

 

Once you get it running again, change the oil, run it a bit, and change it again. Any of that debris will fall to the pan and you want it gone.

Looking at the amount of varnish and what appears to be sludge it has gotten hot.

Good luck.

 

The valve and spring look good from what I can see, would I be able to tell if the valve seat was "dropped" at this point? I'll take a better picture when I get home.