Sup guys. New to the forum. My father in law just picked up a sweet 99 cherokee sport. Guy said it slung a rod. I tore into last night and found the following. First off no slung rod. The engine manually spins over fine. The block was full of coolant. Its an auto 4.0 4wd with only 133k miles on it. I am going to pull the head in the next few days. With this amount of coolant in the block, does this sound like a blown HG or cracked head? Thanks in advance.

 

Tough to say, just inspect the head. Might as well just spend the money on a new and improved head while you've got it all apart. One empty wallet now will save an empty bank account later down the road.

 

Yea thats what i was thinking. Ive been reading about the bad luck with the 0331 heads. Not sure if this one has it or not. Havnt checked that. I read where a few 99's had them.

 

check the oil. if the head was cracked water would get into the oil, mixing, causing it to turn a redish murky tent, and would smell something horrible (happened with my Chevelle). Not saying this is the only means of checking, but it happened to me so thought I would share my 2 cents.

 

Thats the first thing i checked. It read about half way up the dipstick. I dont know if he drove it for a while with a blown HG and it just accumulated that much, or if something went south and sucked all the coolant in at once.

 

bring head to machine shop , have magnafluxed for cracks etc.

no cracks, have it tested for valve seal integrity, (leak down test?)

if all is well, then probly had a blown head gasket and PO didnt want to take time or money to fix.

if cracked, get new head. some pretty decent choices out there.


my 2 cents worth of drivel, an best of luck!


cpnwrench

 

Thanks for the replies guys. We will see what it looks like when i take the head off.

 

I haven't seen any actual proof of a 99 having the 0331 head, but all you have to do is look about halfway down on the drivers side of the head and the head number will show in the casting. My guess is that your 99 has the 0630 head.

 

Thanks for the info bud. Hopefully it is just a HG.

 

Well took the head off last night and found the problem. The second to last pushrod was bent. The back piston is missing! After i pulled the head and moved the intake and exhaust manifold over, i could see the big hole in the block. Dont see how that could have happened with the mileage that was on it. Guess i will be picking up the replacement engine today at a local junk yard. Found one out of a 99 2wd with 101k on it for $550.

 

yeah that could be a problem! good luck, I'm rebuilding my 90 engine now hoping to avoid a hole in the block.