76 Chopokee

So my newest Jeep failed emissions hard, which was expected, since I'm pretty sure the entire system is stock (with 240k miles). The exhaust manifold was cracked in two places upon inspection, the front pipe was split, the tailpipe is rusted beyond belief and the muffler/converter are fused together from heat. I cut the old system out entirely and ordered new parts, predominantly from Walker (through AAP). New front pipe, new exhaust manifold, new tailpipe, new catalytic converter, new muffler, new O2 sensor. At present, my top end is completely disassembled, intake is off, and I pulled the valve cover to have a look (it was leaking too).

Grime-wise, under the valve cover is pretty clean. Looking through the runners to the valves, though, you see that just about every valve is quite nasty looking. The runners themselves are obviously fairly gunky too. The Jeep ran fine when this stuff came apart, other than the emissions stuff. I've replaced all of my heating/cooling hoses, just about every sensor, spark plugs, wires, distributor cap, and even did the Bosch 710 fuel injector swap with the increased FPR.

So now would be the ideal time to pull the cylinder head and have it rebuilt, since the bolts are accessible and I won't be wanting to pull this stuff apart again. It works fine but looks nasty and I'm wondering how much life I'll even get out of it if I put it all back together as-is.

I'm just looking for personal opinions; what would you do? I don't necessarily have the money to pay 200-300+ for a new head gasket, valve job, etc. I also don't know what I could do on my own to help clean it up and run better.

MonacaYankee

Just clean what you can and reinstall the head. No point in having a rebuilt head on a "worn" out everything else block. For only a few hundred more you can get a low mileage 4.0 to swap in which would be a better investment. Now would be the time to yank that block out...just saying.

Maybe look for a head from a part out to swap on. That is what I would do on the cheap.

76 Chopokee

Unfortunately a motor swap isn't feasible right now, I just don't have the time to put into it. So, from your post and from some more thought, perhaps it's best to just run the until it blows up and then do just that. I could do some real port cleaning while it's bolted on if I had a superhero vacuum cleaner and ***** of steel, but I don't trust myself to not drop tons of grit into the engine.

I'm on the fence about spending much more on it if it breaks. I got the Jeep for $40, but she's in real good shape considering that fact. Straight body, no dents, minimal rust, no modifications. I'm a grand deep into it now and really hoping I don't regret spending the money and end up replacing the entire motor within a year.

cruiser54

Put it back together. Add a can of BG44K to a full tank of gas. Run it down to 1/2 tank and fill with gas again, run to 1/4 tank.

Your block isn't worn out anyway most likely and all you're seeing is normal residue from our ****ty fuels these days. No worries.

76 Chopokee

Thanks. It hasn't been driven much at all in the last few months, so I'm sure it's still in the process of blowing out all the crap that accumulated from poor ignition and fuel delivery. Almost all of the spark plugs had cracked insulators and looked awful, all of the wires were corroded, the fuel injectors were extremely dirty.. fixing those (done) and running it (with some cleaner at your suggestion) could do wonders on its own.

RTorrez1

What kind of Jeep are you talking about? Just wondering since you say you have 8 spark plugs.

76 Chopokee

Whoops! Meant 6. Still getting used to that!

RTorrez1

It happens. I was a little confused though.