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Engine 1990 5.0- Overheating and Smoke after Head Swap (Need advice ASAP)

  • Thread starter Thread starter Tango_Yankee
  • Start date Start date Jan 25, 2019
  • Tags Tags
    cylinder heads head gasket overheating
T

Tango_Yankee

Member
Nov 4, 2018
29
6
13
Fredericksburg Virginia
Jan 25, 2019
#1
  • Jan 25, 2019
  • #1
I'm getting desperate at this point.

So, I had bad compression in two of my cylinders and my car drank coolant before I started this job nearly two months ago, so figured I would check the head gaskets. I have never had this engine open since I got the car. At the same time, I pulled some GT40p heads from the junkyard, had them surfaced, cut, and checked for cracks and put them on the car with an early explorer upper and lower intake as well. I got good gaskets and put everything back together with the right torques and, to my knowledge, in the correct orientation.

Today, I tried to start the car for the first time and it was great for the first couple minutes of idling. There was some smoke coming from the tail pipes, but it wasn't too serious. I was filling up the coolant slowly as it drank it from the radiator. However, after a few minutes of idling and occasionally raising the rpm to around 2k, more and more smoke started pouring out the back. Within a few minutes as the engine got hot, it was dumping huge clouds of white smoke out of the pipes. I hoped that it was just the extra crap burning out of the pipes, but it was seriously thick smoke.

After a few more minutes, it explosively began to overheat. Coolant started boiling into the overflow container and actually managed to push vapor past the big c-clamp on the lower radiator hose. Both the water pump and the thermostat are brand new. I stopped the car and vaporized coolant continued to boil out for many more minutes.

I'm absurdly frustrated with this whole thing and I really want to see if there is anything I can do before taking this whole thing apart AGAIN. Did I install something wrong? I put the head gaskets on with the "front" facing the front, so I know I'm not blocking the wrong water jackets. If I dinged up the head gaskets while installing them, could that be a cause? I'm going to do a compression check as soon as I get home and I'll post the results. Until then, is there anything else that could be causing this? I'm ready to bash the car to pieces with a wrench.
 

General karthief

wonder how much it would cost to ship you a pair
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Jan 25, 2019
#2
  • Jan 25, 2019
  • #2
Let us know what the compression test shows. Did you use new head bolts?
 
T

Tango_Yankee

Member
Nov 4, 2018
29
6
13
Fredericksburg Virginia
Jan 25, 2019
#3
  • Jan 25, 2019
  • #3
General karthief said:
Let us know what the compression test shows. Did you use new head bolts?
Click to expand...
Yep, brand new everything. I'll be home in just over half an hour and I'll post results then.
 
Reactions: General karthief
T

Tango_Yankee

Member
Nov 4, 2018
29
6
13
Fredericksburg Virginia
Jan 25, 2019
#4
  • Jan 25, 2019
  • #4
Damnit, of course it's the worst case scenario. Two of my cylinders are totally down and both of them are on the opposite banks, so I have to pull the whole thing apart anyways. Here are the numbers I got.

1: 115
2: 117
3: 65
4: 110
5: 115
6: 40
7: 115
8: 110

I don't quite know why just those cyliders bit it. I'm hoping to the car gods that the block isn't warped or that I scratched it when taking off the old gasket. I did have to wrestle the heads on alone, so I'm hoping that I just scratched the gasket. Looks like I'll be burning the midnight oil to take this thing back apart.
 
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