I own a 2003 f150 with 4.6 Windsor. In the spring I had a plug fly out of the cyl. I had a shop down the road put a thread insert in and I decided I had the plugs already so I will change the rest. Long story short I was in a hurry and did not blow air around the plug hole before plug removal as I usually do. A stone sitting on intake rolled into cyl. I pulled the heads.


Fast forward to present got everything assembled the other night put straight water in it for intial start up then will change if all is good. Ran it to operating temp ran fine. I went to drain water out today to put proper coolant In checked the oil and level was over full and the oil was chocolate brown. Put rad pressure tester on rad and watch drain plug it will drip quite steady.


Unfortunatly I did not measure heads for flatness before assembly and I know better. New head bolts where used and torqued properly. I am about to pull everything back apart just checking for anything it could be before heads come back off. I cant see it being intake as I don't believe there is any location where oil can meet water. I have read about core plugs behind timing cover leaking coolant into timing case. Are the heads common to warp? I don't think it would be the oil filter housing as It was not removed and I had no water in oil issue in spring before I removed the heads. Any ideas appreciated.

 

Well, It could be that the heads, or a head are cracked. So even if new gaskets and head bolts are used, it might be a coincidence they let go after the repair?? maybe before pulling the heads do a compression test and leak down test. Make sure that you don't have cracked cylinder wall.

Could be a defective head gasket or possibly a improperly installed one?? I wouldn't rule out the oil filter housing either.

I seems like you know what is needed going forward. Pull the heads get them checked/rebuilt and start again. Aggravating and frustrating work when things don't go well.

 

I just went through something similar on a Mopar engine that blew a head gasket. After putting it all back together (heads were rebuilt and block was flat.) the heads weren't sealing and a smoke test showed smoke coming out adjacent cylinder spark plug holes and the crankcase. As it turns out even though I used new bolts I didn't run a tap down the head bolt holes, mostly because I didn't have a 4-1/2" long tap and was anxious to get it back together. There was just enough binding in the head bolt threads to keep the heads from pulling all the way down. So I ended up ordering a 6" long bottom tap, removing the bolts one at a time, running the tap up and down a few times, blowing out the holes, and then installing yet another new bolt. Did the torque/TTY thing and all has been well with it since.

So my point is if you didn't do something like chase the head bolt threads the head might not be pulling down and sealing the head gasket.

 

I am leaning towards warped head just because the truck has never been overheated and they where fine when I took them off in the spring. I am going to remove the front chain cover while maintaining rad pressure to ensure the core plugs are not leaking coolant into front cover. Also I think I will remove and regasket the filter housing aswell and recheck. In the end I am pretty sure I will be pulling heads. Thanks for the suggestion. On the bright side it justifies buying the $300 blue point cam lock tool lol.


Good advice alloro I will be running a tap down if the heads are removed again.

 

That's an argument against, not for, them being warped.

 

I meant I don't think they will be cracked as it has never overheated. Being aluminum I suspect warping. Front cover will be off tomorrow to inspect the core plugs for leaking. I am going to replace the oil filter housing gasket and re pressurize. If no problems pop up the heads will be removed.

 

Well I am quite confused now. valve covers off, timing cover off, pressure tester on rad at 16psi and no evidence of water leaking internally. Drain plug remover and no water dripping out oil pan. To fill the oil pan with atleast 2lt of water while engine is running I would expect to have some leakage when shut off. I realize heat will cause expansion but I would expect water intrusion to still be present cold just at a slower rate. I guess I will pull heads and send them out for crack detection and flatness check. Also run tap down bolt holes as mentioned and insure gaskets where installed properly.

 

Here is a update I just got the left cyl head off tonight. It seems I placed the head gasket down correctly however as I was placing the cyl head the o2 harness slipped between gasket and head. I will order new gaskets and head bolts tomorrow, measure the block and head deck to be sure they are straight and reinstall. Thank you for the suggestions.

 

Do you mean you were setting the head a second time and that happened or do you mean the harness got pinched in there the first time and is what caused this issue?

 

The harness got pinched during the first install. I just got lucky last night that the left head was the first head I removed and was the one that had the 02 harness pinched.

 

I hope torqueing the heads down with the wire in-between didn't cause any warping or cracks to the head. Hopefully it's the head gasket that took the brunt of the giving.

 

Here is the final update. Reinstalled the cyl head with out the o2 harness under it and no issues. Water is staying on the water side and oil is staying on oil side. Thanks for all the replies and suggestions.