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Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go hereXJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.
2001 Jeep Cherokee sport. Just received my new Clearwater cylinder head today and noticed a few extra threaded holes? One is next to the ground bolt on the left side if looking at it from the front. One is on the top which looks like it possibly leads to the coolant? The other two are missing stubs on the right side if looking at the engine from the front. Any ideas? Do I need to plug any?
Okay, the one on top is threaded 1/8 NPT and is for a rear temp sensor and must be plugged. They put an unsealed plug in mine and painted over it. It started leaking 2 days after I got it running! I absolutely freaked out! The ones where your finger shows are locating dowels for the intake manifold. The third one is just an additional grounding point. That's where my PCM grounds.
Okay, the one on top is threaded 1/8 NPT and is for a rear temp sensor and must be plugged. They put an unsealed plug in mine and painted over it. It started leaking 2 days after I got it running! I absolutely freaked out! The ones where your finger shows are locating dowels for the intake manifold. The third one is just an additional grounding point. That's where my PCM grounds.
My hero I appreciate you haha. I read another forum that said it took a 1/8 NTP screw but it didn’t say if it was required. Then I couldn’t find anything else about the dowels or other screw hole. I’ll buy a 1/8 NTP plug tomorrow. Any kind you recommend?
I forgot the mention the Clearwater head I bought is in my 2000 WJ because that cracked at 158K and is currently on the rebuilt engine I installed at 253K. The original engine got up to 240* ONCE and the head cracked shortly after that.
One other thing to keep in mind. Because of the cast iron exhaust manifolds, the valves tend to run hot when pulling a load at 1500 rpm or less. It's best to shift down and keep her around 1800 or better at large throttle openings producing power, to lessen the chances of burning exhaust valves. This seems to be a problem just with the cast iron manifolds however. It's quite hilly where I live so I run in 3rd gear at 45 mph a lot. The engine seems to respond better that way.
I forgot the mention the Clearwater head I bought is in my 2000 WJ because that cracked at 158K and is currently on the rebuilt engine I installed at 253K. The original engine got up to 240* ONCE and the head cracked shortly after that.
One other thing to keep in mind. Because of the cast iron exhaust manifolds, the valves tend to run hot when pulling a load at 1500 rpm or less. It's best to shift down and keep her around 1800 or better at large throttle openings producing power, to lessen the chances of burning exhaust valves. This seems to be a problem just with the cast iron manifolds however. It's quite hilly where I live so I run in 3rd gear at 45 mph a lot. The engine seems to respond better that way.
I have an automatic transmission, I don’t think I really have a choice?
05-28-2020, 11:29 PM
Clearwater cylinder head extra holes?
