My first post here, thanks in advance for all your help. Also here's a pic of the Jeep on the shoreline of the lake by my house:
I just bought this '99 TJ Sport about two weeks ago, and after wrenching on it for the last two weeks for various things (tune up, soft top zipper maintenance, removing the light bar and associated wiring), I noticed a problem with the oil pressure when idling after the engine has warmed up.
After doing a little research, I saw this thread:
Cracked 0331 cylinder head castings - JeepsUnlimited.com Forums
About a chronic problem with the 0331 cylinder head cracking. I don't know yet if I'm losing coolant (haven't driven it enough), but the oil pressure problem is pretty much exactly the same as everyone else is seeing.
I'm not 100% sure that I have the 0331 cylinder head. I went outside last night with a flashlight but I couldn't find the casting # on the head, I'll try again today when the sun is out. I also opened the oil filler cap and didn't see an obvious crack, which from seeing the photos it is pretty obvious.
Here's where I wanted to get everybody's advice. The plan going forward is to:
1. Verify during the daylight hours which cylinder head I have.
2. Fill it with coolant, drive it all weekend and see if I lose any.
If I don't have the 0331 cylinder head, that doesn't mean that it still couldn't be cracked, but I'm guessing that lowers the chances of it. If I'm losing coolant and having the oil pressure problem without the 0331 head, does that pretty much point to a blown head gasket? What's the parts&labor on that? (that's a bigger job than I'd do on my own)
Also, I plan on driving this Jeep only 1-2K miles/year. I got it mostly as a tow vehicle for my jet ski, and for dirt road / outdoor fun on the weekends. If the problem is either a cracked cylinder head or a blown head gasket, would I be better off buying an extended warranty (like 12 months / 10000 miles), waiting two weeks and then taking it to the dealer for this problem? If a warranty is cheaper than a head gasket job, worst-case I'm coming out ahead, and best-case the cylinder head is cracked and I'm coming out WAY ahead.
Again, thanks for all your help in advance!