So, I have owned my XJ for about 5 years and 80k miles. No major issues, motor runs STRONG especially considering I have 33's and stock gears with an AX-15. Up and i70, back country camping, always starts on the first crank and never lets me down (probably because I take meticulous care of it).

Over the past few years I have noticed that it has started burning coolant a bit more as time progresses. Not a huge amount mind you, but it has gotten to the point that it will burn roughly the amount between low and halfway in the reservoir every oil change (6000 miles or so).

Not a huge amount, but more than it used to burn.

No leaks, I checked thoroughly. No shiny areas indicating a head crack either, I had the valve cover off about 10k miles ago.

What are my first steps here? Compression check? If I'm low on one or more cylinders, do I change the head gasket and/or put a new head in it?

Or just get a JY motor and have it rebuilt locally? I would go stroker if so, especially since my Jeep is my DD and still runs strong, I could take my time on the build, but I'm probably getting ahead of myself here.

 

I imagine a slow weep from the radiator or heater core to be more likely. Head gasket problems will result in combustion gasses entering the coolant system, which will show in a test, as well as cause cooling issues. (Overheating)

 

Cooling system is all brand new. New heater core as of last winter also.
No areas which I can see are leaking (hoses, water pump/t-stat gaskets, etc). I was hoping that it was a leak to be honest (and will still keep checking I guess).

I am almost due for an oil change and will be sending it to Blackstone labs (first oil analysis ever for me). Afraid to see the results, lol.

No cooling issues at all. Never creeps past 210 even on the steepest of grades. I can't see anywhere that coolant would be leaking. And having to top up the coolant res has me worried

 

I'd check every inch of the cooling system with the motor running at temp to see if you have a slow leak somewhere. If it was leaking enough for it to be obvious you'd probably need to top off every trip or six.

Head gasket would be my next stop I think.

 

Pressure check the cooling system with a tester. Test the cap also.

 

Hmm, good call

I will see if I can rent a coolant pressure test kit from the parts store and report back. Thanks for the advice Cruiser (as always)

 

Those pressure testers will get it to leak if it's gonna......