0331 Head & Years - My 99
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0331 Head & Years - My 99
Like all things, the internet is providing me with too many variable answers...
My 99 has a bit too much goopy goop under the oil fill cap. The oil dipstick appears to be decent but I am concerned with the head. Its a 99 4.0 I6. Trucks runs amazing. Coolant is brown right after a flush but we think someone put stop stick in the radiator. Before I replace the radiator, I would like to know how I can rule out a cracked head....
Any info on the 99 year model or ways to determine (I have ordered a oil test kit), is appreciated.
My 99 has a bit too much goopy goop under the oil fill cap. The oil dipstick appears to be decent but I am concerned with the head. Its a 99 4.0 I6. Trucks runs amazing. Coolant is brown right after a flush but we think someone put stop stick in the radiator. Before I replace the radiator, I would like to know how I can rule out a cracked head....
Any info on the 99 year model or ways to determine (I have ordered a oil test kit), is appreciated.
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Year: 1999
Model: Cherokee
Engine: 4.0
No, the head casting number IS visible without disassembling. But you likely will have to do a bit of cleaning on the lip of the head. But definitely can see it without removing a thing, but use a good light.
That being said, if you have a 99 and it has a distributor and spark plug wires, not a coil rail....you almost assuredly have the 0630 head, unless the head was changed somewhere along the way. The 0331 head was standard in all 00-01 XJs.
That being said, if you have a 99 and it has a distributor and spark plug wires, not a coil rail....you almost assuredly have the 0630 head, unless the head was changed somewhere along the way. The 0331 head was standard in all 00-01 XJs.
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Year: 2000
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Engine: Golen 4.6L
Look on the driver's side next to the #4 cylinder. You should be able to see the number peeking out from under the valve cover without having to remove it. If you have a '99, yours came from the factory with a 0630, which has the casting mark in the exact same place.
Even though it's extremely unlikely you have a 0331, you could still have a blown head gasket, which can manifest with the same symptoms. And 0630 heads and 4.0L blocks can also crack in certain conditions. They just don't do it nearly as often as 0331 heads.
The oil analysis will tell you if you definitively whether you have coolant in your oil. If you do, plan to change the head gasket and inspect thoroughly for other damage when you have the head off.
Even though it's extremely unlikely you have a 0331, you could still have a blown head gasket, which can manifest with the same symptoms. And 0630 heads and 4.0L blocks can also crack in certain conditions. They just don't do it nearly as often as 0331 heads.
The oil analysis will tell you if you definitively whether you have coolant in your oil. If you do, plan to change the head gasket and inspect thoroughly for other damage when you have the head off.
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No, the head casting number IS visible without disassembling. But you likely will have to do a bit of cleaning on the lip of the head. But definitely can see it without removing a thing, but use a good light.
That being said, if you have a 99 and it has a distributor and spark plug wires, not a coil rail....you almost assuredly have the 0630 head, unless the head was changed somewhere along the way. The 0331 head was standard in all 00-01 XJs.
That being said, if you have a 99 and it has a distributor and spark plug wires, not a coil rail....you almost assuredly have the 0630 head, unless the head was changed somewhere along the way. The 0331 head was standard in all 00-01 XJs.
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I replaced the valve cover a few weeks ago and even the top (inside) of it had milky residue.....its very odd.
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Year: 1999
Model: Cherokee(XJ)
Engine: 4.0L
Probably condensation on the cap. Short trips will do that. You need to really drive on the interstate for a while to get the water to boil out of the oil and system.
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Year: 1996
Model: Cherokee
Engine: 4.0L
It's a pretty common thing for older cars in the winter to do this. A couple things can cause this.
1. A bad thermostat, not allowing the engine to warm up enough, such as stuck open or opening too early. Or too low of a temperature of a thermostat (should be 195 degree)
2. You're short tripping it and not letting it get up to temp, such as a not getting on the highway much.
3. Bad head gasket.
1. A bad thermostat, not allowing the engine to warm up enough, such as stuck open or opening too early. Or too low of a temperature of a thermostat (should be 195 degree)
2. You're short tripping it and not letting it get up to temp, such as a not getting on the highway much.
3. Bad head gasket.
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Year: 1990
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0331 head won't fit on a 99 as far as intake and exhaust ports.....
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1. New T-Stat & 195
2. New Water Pump
3. Radiator leaking since flush and heater core flush (was stop stick plugging things up)
4. We know I need a radiator.....
BUT, why is the valve train so damn milky? Head gasket is all I can think of.
2. New Water Pump
3. Radiator leaking since flush and heater core flush (was stop stick plugging things up)
4. We know I need a radiator.....
BUT, why is the valve train so damn milky? Head gasket is all I can think of.