Okay so I bought a 99 grand cherokee (I know its not an xj but this shouldn't matter I didn't feel like registering to a different forum) with a whole in the block. It knocked and smoked and there is antifreeze in the oil. I took the head off and it looks fine. I have a spare engine from my dads 99 grand cherokee. His was fine then one day he started it and it was ticking bad no smoke tho. He got a new motor. Today I took the head off of his old motor. 2 pushrods were bent and 2 others were like pushed down in the block. I think they pushed pushed holes next to the "nozzles" that I guess shoot oil up. Sorry I'm a newbie. The "nozzles" that the pushrods sit in look fine but the holes were created next to the nozzles. Did the pushrods make these holes or were they already there? If not can it be fixxed? What I am wondering if this block is usable or fixable. Thanks for any opinions
bent pushrod?
- Thread starter abc20abc
- Start date
Talyn
NAXJA Forum User
- Location
- Radford, Communistwealth of Virginia
The push rods didn't make any holes in the block. You are probably seeing the oil drain back holes. Those Nozzles are the lifters.
You do need to find out why the push rods let go though.
You do need to find out why the push rods let go though.
joe_peters
NAXJA Forum User
- Location
- Grants Pass, OryGun
Pull the valves and check the guides--probably galled.
Ok I see some oil drain holes but it looks like 2 of the holes are very rough (like as if the pushrod cracked through the block.) Even if that happened would it even matter because the oil goes down there anyways right? About the pushrods letting go what could do that? I'm going to change the head. Could anything in the block cause that to happen? I'll put new lifters in anyways..
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Talyn
NAXJA Forum User
- Location
- Radford, Communistwealth of Virginia
Towards the rear of the block there are 3 oil drain holes. Two are larger and have a bunch of casting flash, and one between the two looks like some one simply punched a hole in the block. All normal. They are ulgy.
I wouldn't put new lifters in unless you need to. I also wouldn't install new lifters without first finding why the push rods moved. I would pull the lifters with the bent pushrods and look at the bottom of the lifters and the cam lobe. Do keep the lifters in order thought. The lifter should have a polished bottom with no pitting or holes and a slightly convex (domed) surface. You can't tell its convex by looking at it but if you put a completely straight edge on it you will see the high spot in the center. If you can post pics of the lifter bottom and I will tell you if I see anything that jumps out. As well as checking the valve for binding in the head. I wouldn't just swap on a different head just because.
If you do have a lifter that is damaged the cam is damaged as well and you would need to replace that.
I wouldn't put new lifters in unless you need to. I also wouldn't install new lifters without first finding why the push rods moved. I would pull the lifters with the bent pushrods and look at the bottom of the lifters and the cam lobe. Do keep the lifters in order thought. The lifter should have a polished bottom with no pitting or holes and a slightly convex (domed) surface. You can't tell its convex by looking at it but if you put a completely straight edge on it you will see the high spot in the center. If you can post pics of the lifter bottom and I will tell you if I see anything that jumps out. As well as checking the valve for binding in the head. I wouldn't just swap on a different head just because.
If you do have a lifter that is damaged the cam is damaged as well and you would need to replace that.
watrousmark
NAXJA Forum User
- Location
- Antioch Tn
Sounds like your dad had a nice hydraulic lock happen. Ask him about the conditions when he had trouble. Also check the condition of your timing chain, if it broke or jumped time that would also bend pushrods.
Talyn
NAXJA Forum User
- Location
- Radford, Communistwealth of Virginia
The 4.0L isn't an interference engine. Thanx for playing though.
