Overheating - already replaced head gasket, water pump, thermostat
#16
Can machine shops fix cracks? The one I took it to could not detect a crack in the head. I'm just wondering if they missed it. I'll grab that pressure test kit in the next day or 2 and give it a try. Any place I can read instructions on how to use a kit like that?
#23
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 19
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Yea! ^, And don't get an 0331...unless you can find a "tupy" foundry mark inside under the cap. That's the " revised" 0331.
Like Old Blue mentioned. If it has 0331 on the drivers side, top edge it it almost centennially toast. I guess the 0630 is a pretty hardy head though. I doubt it's the bolt, sounds like a crack. Did the shop magnaflux it? If not that might be your next move. You could pressure test, but with milky oil...Idk. And no, no sealant for a head gasket, just that one bolt.
Do take some time, when you have the head off, with a really good light take a really good look at the cylinder walls. They DO crack, and sometimes you can see it. (you might do that first). Sorry btw. Years ago my feonsay melted a motor of mine, was only a mile home (after the light came on), but it was nearly straight up!
Like Old Blue mentioned. If it has 0331 on the drivers side, top edge it it almost centennially toast. I guess the 0630 is a pretty hardy head though. I doubt it's the bolt, sounds like a crack. Did the shop magnaflux it? If not that might be your next move. You could pressure test, but with milky oil...Idk. And no, no sealant for a head gasket, just that one bolt.
Do take some time, when you have the head off, with a really good light take a really good look at the cylinder walls. They DO crack, and sometimes you can see it. (you might do that first). Sorry btw. Years ago my feonsay melted a motor of mine, was only a mile home (after the light came on), but it was nearly straight up!
#26
Pressure checked showed a leak..took off valve cover and saw some fluid seeping out of a crack in the top part of the head...thanks for the recommendation.
I'm looking at the Spartan cylinder head from Advance Auto...My local junk yard carries a head for $150 plus the cost to have it checked after I bought it buy a machine shop. So it's around $200 for a jy head or about $380 for a remanufactured head from Advance Auto.
Any reason why I shouldn't purchase the one from Advance? Will it hurt anything to put a head like that on a 13 year old engine block?
I'm looking at the Spartan cylinder head from Advance Auto...My local junk yard carries a head for $150 plus the cost to have it checked after I bought it buy a machine shop. So it's around $200 for a jy head or about $380 for a remanufactured head from Advance Auto.
Any reason why I shouldn't purchase the one from Advance? Will it hurt anything to put a head like that on a 13 year old engine block?
#27
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 16
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
Sorry to change the subject, but can u verify whether or not your '99 XJ's head is original?, can it be identified with the 0331 marking?, what is the "build date" of your '99 XJ? (sticker on the drivers door pillar, Mo/Yr)
#28
It's actually the 0630 head...original. I've owned the vehicle since 1999. It's not the weak one that everyone keeps talking about but it is definitely cracked. Pressure test shows the liquid bubbling out at the head top portion near the valve cover.
My oil doesn't look milky though --- only in the valve cover is it milky..dipstick shows it clean looking.
My oil doesn't look milky though --- only in the valve cover is it milky..dipstick shows it clean looking.
#29
Would a small head leak cause the engine to overheat after ten minutes? That head crack is small and is only leaking a little fluid. I can see a head leak causing a miss but would it cause an overheat that fast?