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Is my 0331 cracked? Pics Inside.

erykv1

NAXJA Forum User
Location
earth
Hello CF,

I've been experiencing a slight overheating (http://www.naxja.org/forum/showthread.php?t=1129291) recently and after combing through my 4 month old cooling system (new rad, new t-stat, new waterpump, new hoses etc) and giving it another flush with no avail... I took a peek under the oil cap.

My XJ is an 01 with the 0331 head. I've always been careful with it, but I guess not careful enough. I have never let it overheat into the red.

I have not experienced any common symptoms of a cracked head (coolant loss, milky oil, or milky trans fluid)... only this recent overheating and a slight sheen in the coolant overflow. Oil pressure has been fine.

Could someone experienced take a look at these pics and tell me if its a crack? Just to give some orientation of the photos, the top is facing the drivers side.


80-akoeryt_c337690a9a539b2bd2ae095e898e8428a72ce2c7.jpg


80-hzoq3kn_9bd9f505776e05be2a60c92ecca90d3279eb003c.jpg


80-wabxhbd_eff975acaf3b531bbdd4b785dc6acb5c72ea65fc.jpg


If this looks like a cracked head, could someone still point me in the direction of where I can buy a TUPY/updated head? Is clearwater still the recommended company? I would like something I can drop in and not have to worry about swapping valve springs / valve stem seals

Also, since I hope I caught it early... just swapping the head should be sufficient right? Is there a complete list of what I need? I'm assuming, head, valve cover gasket, head bolts? Do I need intake manifold / exhaust gaskets or can I copper spray and reuse the ones on there?

Thanks! :roll:
 
a reman head should come loaded ... i.e. valves and such all installed.

you will need

Head gasket set . . if not supplied with the head
head bolt set
liquid teflon sealant
oil and filter
antifreeze
anti seize lubricant
penetrant oil PB blaster is the best I've found yet.

if you have an engine crane, that's a plus for lifting the head off and out.. and you can do it with manifolds still attached.
 
When I tore mine down I saw stuff like that even on the replacement. I look for tan lines or obvious coolant traces. You can also do an oil analysis to see if coolant is excessive. That way if it is, you may not know for sure if its the head or head gasket, but the general rule of thumb on factory original 0331 head is to replace them if you pull the head for any reason (such as to replace the gasket). This looks suspect but is not a clear indicator. Hope that makes you feel better.
 
It could be a casting imperfection, But the sheen in the coolant bottle is a good indicator that it may be a cracked head/Bad head gasket.
Drain your oil & see what it looks like & send a sample to blackstone to have checked for coolant.
I would not drive it until the problem is solved, coolant is bad for bearings.
Good Luck!
 
When I tore mine down I saw stuff like that even on the replacement. I look for tan lines or obvious coolant traces. You can also do an oil analysis to see if coolant is excessive. That way if it is, you may not know for sure if its the head or head gasket, but the general rule of thumb on factory original 0331 head is to replace them if you pull the head for any reason (such as to replace the gasket). This looks suspect but is not a clear indicator. Hope that makes you feel better.

It could be a casting imperfection, But the sheen in the coolant bottle is a good indicator that it may be a cracked head/Bad head gasket.
Drain your oil & see what it looks like & send a sample to blackstone to have checked for coolant.
I would not drive it until the problem is solved, coolant is bad for bearings.
Good Luck!

Thank you guys. Yeah I havent driven it much since it started overheating.

I will probably do a block test this weekend and know for sure.

The oily sheen I noticed when I flushed the coolant a few weeks ago, it hasnt come back yet but I've also only put like 40-50 miles on it if that.
 
Start it up, if it turns green ... It's cracked.
Panic not.
When mine cracked I had no coolant loss, no oil sheen, no milky oil. Didn't even know it was cracked until I went to add a bit of oil and noticed the green coolant through the fill hole.
Simply swapped a 93 head on hung the coil rail and converted the exhaust .... been driving it since (11yrs now) bearing are still the originals. Runs fine and reliable.

Sent from my SGH-I337M using Tapatalk
 
Start it up, if it turns green ... It's cracked.
Panic not.
When mine cracked I had no coolant loss, no oil sheen, no milky oil. Didn't even know it was cracked until I went to add a bit of oil and noticed the green coolant through the fill hole.
Simply swapped a 93 head on hung the coil rail and converted the exhaust .... been driving it since (11yrs now) bearing are still the originals. Runs fine and reliable.

Sent from my SGH-I337M using Tapatalk

thanks for the input.

did you have to get new manifolds? I've considered getting the 0630 head but it seems like more work than its worth.
 
Yeah, used a standard HO manifold, get it when you get the head.
Being you have an 01 really limits your choices. You could simply add all 4 02 sensor bungs (top two one one cylinder 1-3, second on 4-6 runner junction, and then run the lowers on a pair of 02 sensor elbows) to keep the ecm happy and allow use of the 7120 or 0630 heads. Coil rail can be hung off the valve cover bolts (use the studded ones). Add a little exhaust work, and your done once and for all.
Or seek out a TUPY casting. Buying new/reman will run about the same as the head swap so just a decision as to how much effort you want to do.
Of course depending on where you live legality issues may arise as a result.
Much easier on the 00's without the precats and associated ecm involved.

Sent from my SGH-I337M using Tapatalk
 
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